Sigasi Studio Manual


Setting Up Sigasi Studio

Distribution and Flavors

Sigasi Studio is distributed online. It is available in two versions: as a stand-alone application or as a plugin inside a standard Eclipse installation. Your license gives you the right to use either version, at any time, at your discretion. Therefore, your first task is to decide which version suits your requirements, based on the description below. Depending on the chosen version, you should then follow the corresponding installation instructions.

Sigasi Studio App

The stand-alone application has the following characteristics:

  • Recommended if you are not using Eclipse yet
  • Installation is trivial: just unzip!
  • Everything is included in a single download
  • Well-balanced set of features
  • Optimized for VHDL and Verilog development
  • Complete freedom to add and configure plugins

Sigasi Studio Eclipse Plugin

The Eclipse plugin has the following characteristics:

  • Recommended if you are using Eclipse already
  • Easily plugged into your existing Eclipse platform
  • Complete freedom to add and configure plugins
  • Over one thousand other Eclipse plugins to choose from
  • Support for C, C++, Tcl, and other languages
  • Support for many version control systems

Sigasi Studio Custom Installation

  • Recommended for (larger) teams
  • Automates the setup of Eclipse, the Sigasi Studio plugin, and your project
  • Ensure that team members have a uniform setup
  • Quickly set up Eclipse with Sigasi Studio
  • Configure team preferences during setup
  • Check out a project from version control at setup time
  • Optionally add support for other programming languages

The custom installation is documented in a separate section.

Installation of Sigasi Studio App

To download and install Sigasi Studio as a stand-alone application, follow the online Installation Instructions.

After downloading, choose or create a folder where you want to install the software and unpack the archive there. The archive contains a single top-level folder called sigasi. Inside the folder, there is an application startup file, also called sigasi. Start the application by executing this startup file.

If you are using RedHat Linux 6 or CentOS 6, you need to follow the Plugin installation instructions as explained here.

Running Sigasi Studio with multiple users on the same server

The following section is only relevant if you’re using a Sigasi Studio version older than Sigasi Studio 4.17.2.

Starting with Sigasi Studio 3.8, the Sigasi launcher listens on port 4444. To avoid conflicts on this port when Sigasi Studio is used on a server with multiple users concurrently, the following changes need to be made:

  • Edit sigasi/configuration/config.ini and replace eclipse.application=com.sigasi.runner.open with eclipse.application=org.eclipse.ui.ide.workbench
  • In sigasi/sigasi.ini add following lines between @noDefault and -vmargs:
--launcher.defaultAction
openFile
  • If there are other arguments between @noDefault and -vmargs, append to these.
@noDefault
-vm
plugins/org.eclipse.justj.openjdk.hotspot.jre.full.<version>/jre/bin
--launcher.defaultAction
openFile
-vmargs

This way Sigasi Studio uses the default Eclipse behavior instead of the custom Sigasi runner. More information on the Eclipse OpenFileFeature can be found here.

The Sigasi runner allows you to open projects using the -p option. This is not possible when using the default Eclipse runner.

Installation of Sigasi Studio Eclipse Plugin

There are two ways to install the Sigasi Studio Eclipse Plugin:

  1. On-line installation of the Eclipse Plugin
  2. Off-line update site to install the Eclipse Plugin

Prerequisites: Java Runtime

  • The Sigasi Studio plugin requires Java 11.
  • You can check your Java version with java -version
  • Java can be downloaded from several sources, a.o. Adoptium.

Prerequisites: Eclipse

Eclipse Foundation member

For more information on system requirements: System Requirements

Install the Eclipse Plugin

This requires the host where you install the Sigasi Studio Plugin to have access to our download server. After starting Eclipse:

  1. Click Help > Install New Software…
  2. In the Work with: field enter https://download.sigasi.com/updates/studio and press enter.
  3. Check the checkbox next to Sigasi Studio
  4. Since Sigasi Studio 4.15, installing Sigasi Studio optional features is no longer recommended.
    Install Sigasi Studio plugin
  5. Click the Next button.
  6. The following steps are pretty self-explaining.
  7. After the installation, you will need to restart Eclipse. Once this is done, go to Window > Perspective > Open Perspective > Other… and select the Sigasi Perspective. You can then close the Welcome View to show the Sigasi Views.

Installing the Offline Update Site

Installing the offline update site is very similar to installing from the main update site, where step 2 is replaced with these steps:

  1. Download the offline update site
  2. In the Install Wizard, click Add…
  3. Click Archive…, browse to the zip file you downloaded, and confirm with OK.
    Add offline update site archive

Next, continue with step 3. in the general eclipse installation instructions. It is recommended to disable the option Contact all update sites during install to find required software when installing the offline update site.

GPG Certificate Validation

Eclipse 4.26 (2022-12) added GPG certificate checking capabilities. When you install new plugins, you will be prompted to trust any not-yet-trusted GPG keys or unsigned artifacts. Because Sigasi artifacts are correctly signed using GPG, you can expect to see the following screen the first time you install or update Sigasi in an Eclipse >= 4.26.

Previously trusted keys can be inspected by going to Window > Preferences > Install/Update > Trust.

You can refer to this page for all information regarding GPG at Sigasi.

Licensing

The license key can be filled in under Window > Preferences > Sigasi > License Key.

More details can be found here. The license unlocks the features for your edition.

Configuration

Sigasi Studio stores its projects on the file system in one or more workspaces.

When you start the tool for the first time, it will propose to create a workspace for you:

Choose workspace

Although you can work with multiple workspaces, we recommend using a single workspace for all your projects.

Software Updates

Sigasi Studio has an automated update system. When updates are available, you are notified by a pop-up window called Updates Available in the bottom right corner:

Updates Available

If you want to install the updates, click anywhere in the pop-up window. After a few seconds, a new window will appear with further instructions.

The updates can be postponed by closing the pop-up. You can perform the updates at any time by clicking the Update icon-icon in the status bar at the bottom of the screen.

It is good practice to first create a backup of your installation folder before running an update. This can be done by simply compressing the eclipse or the sigasi folder in an archive (zip file)

Update Sigasi Studio App

If you run Sigasi Studio as a standalone application, the automated update system will periodically check for software updates.

Update Sigasi Studio Eclipse plugin

If you run Sigasi Studio as an Eclipse plugin, you may need to check for updates manually, by clicking Help > Check for Updates.

You can enable automatic updates by opening this preference page: Install/Update > Automatic Updates. Next, enable Automatically find new updates and notify me. Feel free to modify any of the available options.

Firewalls and Proxies

If the updates are not automatically fetched from the Sigasi Studio update server you are probably behind a firewall or proxy server. You can configure Sigasi Studio’s proxy settings in Window > Preferences > General > Network connections. Make sure to set the Active Provider to Manual and configure the appropriate Proxy entries. Whether you need to configure the entries for HTTP or HTTPS depends on the Locations configured in the Available Software Sites settings.

If you can not add a firewall exception for our update site, the fallback solution is to download the complete application from our website. You can completely replace your old installation; all settings are stored in your workspace (the default is workspaceSigasi in your home directory).


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Setting Up a Project

Introduction

Your work with Sigasi Studio typically is organized as a project. A project is a collection of VHDL and/or (System)Verilog files that belong together. Sigasi Studio understands the HDL units defined in the files, and the relationships between them.

Your first step is to set up a project. There are a number of ways to do this. The most common ways are:

Mixed language projects

Note that while you initially need to choose between a VHDL and a (System)Verilog project, any Sigasi Studio project can be a mixed language project. If you wish to create a mixed language project, we recommend to import or create a VHDL project and then add the (System)Verilog support to this project.

To create a mixed language project, right click your project and select Configure > Add VHDL support or Configure > Add (System)Verilog support as needed.

Features

In projects you can navigate from instantiation statements to the matching entity or module. This also works in mixed language projects. You can navigate from VHDL entity instantiations in (System)Verilog code and (System)Verilog module instantiations in VHDL code. You can also open the declaration of ports and generics/parameters in mixed instantiations.

Other supported features:

  • Find references for entity names, modules, ports, generics and parameters.
  • Autocomplete (System)Verilog module instantiations in VHDL code and VHDL entity instantiations in (System)Verilog code.
  • Error reporting of incorrect entity names, modules, ports, generics and parameters in instantiations.
  • renames of signals and ports.

Screencast : Mixed languages: instantiating Verilog in VHDL code

Importing a project from the file system

1: Import the project

You can import an existing VHDL or (System)Verilog project from the file system by clicking File > Import… > Sigasi > Import a VHDL project or Import a (System)Verilog project. Browse to the root directory of the project, and press Finish.

2: Set Libraries (VHDL or Mixed)

Since Sigasi Studio 4.4, Sigasi Studio automatically configures libraries of imported projects, based on project information such as library and use clauses. If you need to customize the library configuration, you can assign different libraries to your files and folders. Right-click on a file or folder and select Library Mapping > New Library…. Then fill out the correct library name.

The following chapter gives more information on using libraries.

3: Add any files that are in other directories

If you need additional files that are not in the project root directory, just drag them from your Windows Explorer (or other file browser) into the project. You will have the option to create a link rather than copying the files.

Note 1: dragging files works on Windows (using Windows Explorer), on Mac OS X (using Finder) and on Linux (using Gnome Nautilus). If you use KDE, you should install Nautilus.

Note 2: to avoid absolute paths in the .project file, environment variables can be used. Right-click the file or directory in the project explorer and select Properties > Resource > Location > Edit… to configure the path of the resource. To access environment variables, you have to prefix the environment variable with ENV-. For example: to refer to the home directory you can use ENV-HOME.

Creating a new, empty project

To create a new project, select File > New > VHDL Project or File > New > (System)Verilog Project. Then give your project a name.

By default, the Use default location checkbox is checked, which means that new projects will be located in the workspace folder. Alternatively, you can uncheck the checkbox and choose an arbitrary location for your project. This is especially useful if you want to use Sigasi Studio with an existing design.

You can also select the VHDL version or the version of .v files.

After creating a new project, you can add existing files by dragging them from your filesystem into the project explorer. New files can be added by clicking File > New > VHDL file, File > New > Verilog file or File > New > SystemVerilog file.

Other ways to set up a project

Adding VHDL or Verilog support to an existing Eclipse project

You can also add VHDL or Verilog support to any project in your workspace by right-clicking the project in the project explorer and selecting Configure > Add VHDL support or Configure > Add (System)Verilog support. You can also remove VHDL or Verilog support from Sigasi Studio projects by selecting Configure > Remove VHDL support or Configure > Remove (System)Verilog support.

Note that with a Sigasi Studio XL or a Sigasi Studio XPRT license, you can have mixed VHDL and Verilog support at the same time.

Importing a project from an archive

Sigasi Studio projects can be shared using file archives. All project-related settings are stored in two hidden files in the project folder. Therefore, you can create an archive of the entire top level folder (File > Export > General > Archive file) and send it to someone else.

You can import a project from an archive by clicking File > Import… > General > Existing projects into Workspace and selecting Select archive file. Browse to your project archive and press Finish.

Programatically creating a project

The Sigasi Studio .project and .library_mapping.xml files can be created using code from our publicly available Sigasi Project Creator project.

The project offers Python classes that make it easy to generate a Sigasi Project from your own project specifications. For more information and examples, check out the Sigasi Project Creator project on GitHub.


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Libraries

Introduction

HDL libraries are a very powerful feature of the HDL languages. Sigasi Studio makes it easy to configure and use them. In this chapter, we assume that the basic concepts of HDL libraries are understood. We will explain how they are implemented in Sigasi Studio.

Like with any HDL tool, Sigasi Studio needs to know where the libraries are located on the file system. We will describe how the library configuration can be examined and modified using the GUI.

We will also present some use case about how to set up libraries with Sigasi Studio to organize your projects.

Examining the library configuration

You can examine the library configuration in the Libraries View and in the Project Explorer view. The Libraries view shows how design units are mapped. The Project Explorer view show how VHDL or SystemVerilog files are mapped.

In the Libraries view you can see a tree of all libraries in your projects. You can open each library to see all contained design units.

In the Project Explorer view each physical file or folder is annotated with the library it belongs to, between square brackets:

What you see here is the initial library mapping of a demo project (you can create such a project by selecting File > New > Other > Tutorial VHDL Project or Tutorial SystemVerilog Project).
In the screenshot we see a project called Demo, with a folder named Common Libraries. In that folder, you see the typical standard libraries (std and ieee) upon which all VHDL projects depend. The demo project itself consists of a few VHDL files.

Next to the project’s name Demo, is the annotation work. This means that, barring any overrides, everything in the project will be stored inside the work library.

Lower down, we see overrides. For example, the STD folder has an annotation std. This means that, again barring any further overrides, the entire contents of the STD folder will be mapped into the library std. There are no limits to the number of overrides that can be performed. If this needed, any individual file can be mapped to a separate library.

Modifying the library configuration

The library mapping for project files can be modified in the Libraries and Project Explorer view.

Select a file or a folder in the Project Explorer and right-click.

You get a Set Library context menu, with a number of options:

  • Select Exclude from build to exclude the file or folder from any library
  • Select New Library… to define a new library and map the file or folder to it
  • If one ore more folders are selected, the folder can be added to a library with the folder name(s)
  • Select the name of an existing library to map the file or folder to that library

When you map a file into a library, only that file is affected. However, when you map a folder into a library, then everything in that folder will be mapped into that library. Any overrides in the folder and its sub-folders will be removed. When you are defining the library mapping for a new project you should map from top to bottom.

So in the case of our Demo project, you would change (if work is not a good default) the top folder’s mapping first and then override the mapping in the sub-folders.

When you are changing the library mapping of a project, the project will be rebuilt completely. In order to avoid several consecutive rebuilds while you are setting up your libraries, you can temporarily disable the automatic rebuilds, until you are finished setting up your library mappings. You can do this by disabling the Project > Build Automatically option.

To exclude a file from all libraries, the library mapping context menu provides an Exclude from build option. You can apply that to any file or folder in the project. Sigasi Studio will then assume that the corresponding resource is not a part of the project and will not include that resource in a project build. This is typically useful when you have stale copies of HDL files or folders lying around that you want simply to be ignored.

(System)Verilog include files

(System)Verilog include files are always excluded from the build. Any file that is included in another design file gets excluded from the build, even if it has an extension that would normally identify it as a design file, e.g. .v or .sv. It often doesn’t make sense to compile include files by themselves. Instead, include files are compiled in the context of the file in which they are included.

Configuration file

All library configuration information is stored in the .library_mapping.xml file in the root of your project. If you edit this file, your project will be cleared and rebuilt automatically (a so-called Clean Build).

Sigasi Studio only writes changes to this configuration file when you make changes to the library configuration with the context menu in the Project Explorer. When you do make changes, Sigasi Studio first checks that all paths in the library configuration still exist. If a path no longer exists, is will be removed from the configuration file. Note that the library configuration file is case-sensitive, even on Windows.

Library configuration warnings and Quick Fix

If the library mapping file contains invalid entries, there will be a warning on the .library_mapping.xml file. This warning will show in the Project Explorer, in the editor and in the Problems View.

An associated Quick Fix is available through the Problems View. When invoked, it will remove all invalid entries from the .library_mapping.xml file.

Common Libraries

Each VHDL project has a folder called Common Libraries. This is where reusable libraries go: either vendor libraries, third party IP libraries or your own reusable libraries. By default, the STD and IEEE libraries are added to this folder. The Common Libraries folder behaves like any other folder. You can delete it, rename it and apply a different library mapping. In most cases, however, the default configuration is just what you need.

If your project doesn’t have a Common Libraries folder, you can just create it by right-clicking the project in the Project Explorer and selecting the New > Folder dialog.

How to add files to Common Libraries?

In any newly created VHDL project, the Common Libraries folder contains the VHDL files of the IEEE and STD libraries.

To add files to the Common Libraries folder, locate a folder with VHDL files on your file system using the Project Explorer or the file explorer of your OS and drag the folder with VHDL files to the Common Libraries folder.

Alternatively, you can right-click the Common Libraries folder and select the New > Folder dialog where you can use the Advanced » settings to create a Linked Folder pointing to the actual folder location that contains the files you wish to add to the Common Libraries.

How is Common Libraries different from another folder?

  • Common Libraries by default is a virtual folder. This means that it is not a real folder in the project directory and it can only contain references to folders on your file system.
  • Files in Common Libraries are supposed to be error free. Sigasi Studio will not mark errors or warnings in these files.
    • Next to these, a few other libraries’ errors and warnings are never marked, regardless of their location. These libraries are: std, ieee, altera_mf, altera, XilinxCoreLib, unisim, mentor, lpm, simprim, std_developerskit, unimacro, and modelsim_lib.
  • While you work on your project, you don’t want to edit the files in the Common Libraries, but you need them to compile your project.
  • If you activate an external compiler, files in Common Libraries are supposed to be pre-compiled. If you tell Sigasi Studio to compile your project using an external compiler, the Common Libraries are skipped. You need to pre-compile them yourself and let your compiler know where the compiled libraries are. For ModelSim, you can use the “modelsim.ini” file for this. If your project root contains a “modelsim.ini” file, it will be used instead of the default “modelsim.ini” file.

Pre-compile Common Libraries

This section links to various recommendations on to pre-compiling the simulation models of external libraries in the Common Libraries, depending on the external compiler.

AMD/Xilinx

Intel (formerly Altera)

GHDL

The GHDL manual documents precompilation of Vendor Primitives here.

Riviera-PRO

If you’re using Riviera-PRO, Aldec has an article on Compiling Xilinx Vivado Simulation Libraries for Riviera-PRO.

VUnit

Running VUnit tests

You don’t need to pre-compile VUnit libraries for running VUnit tests. The VUnit framework compiles its own library when needed. If you’re using libraries like OSVVM, you need to call add_osvvm() in run.py to tell VUnit to also compile the OSVVM library.

Further documentation on using VUnit in Sigasi Studio is available here.

External compiler in a VUnit project

If you want to configure an external compiler in a VUnit project (e.g. for additional syntax checking), you need to ensure that the compiler has the VUnit library. Otherwise, the compiler will flag all VUnit constructs in your HDL code as errors.

This script demonstrates how to compile and enable the VUnit library for Modelsim and Questa. Run this script in the folder where you want to install the compiled VUnit library. This should be outside your project folder. The script takes the path of your VUnit installation as a parameter. Once the compilation is finished, go to your project folder and run these commands:

vmap -c  # only if your project folder doesn't contain modelsim.ini already
vmap <folder_where_the_script_ran>/vunit_lib vunit_lib

Note that the OSVVM library is shipped with Modelsim, so you won’t need to compile it yourself.

For other external compilers, a similar approach is needed. Customers who need help with that are welcome to contact support.

What if I broke my Common Libraries folder?

If you have modified the Common Libraries folder, you can always revert it back to the original state. Right-click on the Common Libraries folder of your project in the explorer view and apply menu-entry Set Library > Reset Common Libraries.

Resetting the library mapping

Sigasi Studio contains two functions to reset all or part of the library mapping.

  • Reset Common Libraries updates the common VHDL libraries to the version (‘93, ‘2002, ‘2008, ‘2019) required by your project. User-defined common libraries remain untouched. To access this function, right-click the Common Libraries folder inside your project in the Project Explorer and select Set Library > Reset Common Libraries.

  • Reset Library Mapping resets the entire library mapping of your project. After resetting the library mapping, Common Libraries are reset as above, and all design files are mapped to library work. Note that this action cannot be undone, so only use it when you want to rebuild the library mapping from scratch. To access this function, right-click your project in the Project Explorer and select Set Library > Reset Library Mapping.

IEEE Vital

See How can I use the IEEE Vital libraries with Sigasi Pro?

Shared libraries

Sigasi Studio allows you to share libraries between multiple projects. The easiest way to do this, is to develop each library in a separate project and configure the Project Dependencies accordingly. To configure the project dependencies, right click the project (the one that uses the shared library) and select Properties. Next click Project References and mark the library project as referenced project.

Using third party libraries

Many projects use third party libraries. These can be added to the project as any other set of VHDL files.

A number of popular third party libraries are the following:

VendorLibraryInstall dir example
AMD/XilinxunisimC:\Xilinx\Vivado\2020.1\data\vhdl\src\unisims
AMD/XilinxunimacroC:\Xilinx\Vivado\2020.1\data\vhdl\src\unimacro
AMD/XilinxXilinxCoreLibC:\Xilinx\14.4\ISE_DS\ISE\vhdl\src\XilinxCoreLib
AMD/XilinxxpmC:\Xilinx\Vivado\2020.1\data\ip\xpm
Intelaltera_mfC:\Intel\17.0\quartus\libraries\vhdl
Mentormodelsim_lib${ModelSimPath}\vhdl_src\modelsim_lib
AldecaldecC:\Aldec\Riviera-PRO-2015.02\vlib\aldec\

On Linux the default installation location for AMD/Xilinx software is /opt/Xilinx.

For many common third party libraries, you can set up the library using a Quick Fix for third party libraries.

XilinxCoreLib

XilinxCoreLib is a very big library with more than a thousand entities and architectures. If you include all of these design units, it slows down the compilation phase of Sigasi Studio. In order to avoid that, Sigasi Studio only adds the packages with the component declarations to your project by default. It excludes the entities and architectures from compilation.

You can easily add selected entities (and architectures) to your project by right clicking the corresponding file (filename = entity name.vhd) in the Project Explorer, and selecting Set Library > xilinxcorelib.

Library errors from external compilers

If you are using the External Compilers, the external compiler can also put error markers on library clauses. You can easily verify this by checking the prefix of the error message (e.g. vcom: for vcom errors). Consult the Libraries section of the external compiler integration for more information on configuring libraries for your external compiler.


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User Interface

The Sigasi Studio perspective

Sigasi Studio is built upon the Eclipse platform, which permits to use multiple languages within a single environment. The user interface can be customized for a particular language. In Eclipse terminology, this customized user interface is called a perspective. The icon and name of the current perspective is highlighted in the upper right corner.

Sigasi Studio provides a Sigasi perspective to work with both VHDL and Verilog files.

If you use the standalone version of Sigasi Studio, this perspective is the default. If you use the Eclipse plugin, another perspective may be open instead. You can select the Sigasi perspective by clicking the button next the perspective icon. A window pops up in which you can select the perspective.

You can right-click the perspective button to customize toolbar contents, to reset the perspective to its default layout or to save your own, customized perspective.

Quick Access

The Sigasi Studio toolbar contains a widget called Quick Access. This widget allows you to quickly find open editors, available perspectives, views, preferences, wizards, commands, etc. Simply start typing the name of the item you wish to invoke.


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Views

When you open a project in Sigasi Studio, a number of views are presented in the user interface. Here is a typical screenshot, with the views highlighted.

The views provide alternative ways to access the information in a project. They permit efficient navigation, inspection, and editing.

This chapter lists and explains the most important views of Sigasi Studio. Some views are not covered here, more specifically some views that are either inherited from Eclipse, or views that are provided by third-party plugins. Please refer to the Eclipse documentation or the specific plugin documentation for further information on those views.

You can open a view in several different ways:

  • By typing the view name in the Quick Access field
  • Via Window > Show View. If the view is not in the visible list, choose Other… and select the view in the selection dialog. By right-clicking in the editor and selecting Show in > …. Some views also support opening the current selection (e.g. the Block Diagram View). This selects the element in the view that corresponds to the current selection in the editor.

Project Explorer View

This view shows the directory structure of all files in all projects. You can use it to navigate to a particular file in your project and select it. When you double-click on a file, the file opens in the Editor view. If you right-click a file, you see the context menu which offers extra commands.

You can customize the behavior of the Project Explorer View in ways that can be particularly handy for large projects. For example, if you click the Link with Editor icon Link with Editor , the Project Explorer will be linked to the Editor view. Now, the active file in the editor view will always be selected in the Project Explorer.

You can apply filters to choose which files are shown. Select the icon View Menu View Menu icon and then Customize view. You can then select a filter whose matching files will be hidden in the view. For example, you can filter out all non-VHDL or non-Verilog files.

The Project Explorer View provides textual and graphical Label Decorations which can be controlled in Window > Preferences > General > Appearance > Label Decorations. Label decorators are a visual guide on the state of projects, folders, and files. Decorators can depend on various plugins. The following descriptions apply to Sigasi-specific decorators.

  • Sigasi Studio adds text decorators to the right to indicate which library a project, file, or folder is mapped in. The library name is denoted in square brackets.
  • If a project is in a different folder than the workspace, this is denoted within round brackets.
  • Other text decorators to the right of a project are probably from the Git plugin. The repository name and branch are denoted with square brackets.
  • Open HDL projects have a bridge-like overlay bridge-like overlay icon in the top right corner of the project icon.
  • File icons with a ‘V’ in them are VHDL or SystemVerilog source files.
  • Folder icons with an overlay in the lower right corner are virtual folders (white square) or linked folders (square with arrow).
  • Other overlays in the lower right corner are probably from the Git plugin. They indicate tracked files/folders (yellow cylinder) and non-tracked files/folders (question mark). Changed files are noted with a > mark next to the icon.
  • Overlays in the lower left corner are generally indicating status from Sigasi Studio: errors in files/folders are indicated with a red square and white cross red square and white cross icon while files/folders with warnings are marked with a yellow triangle with black exclamation mark yellow triangle with black exclamation mark icon .
  • If you exclude a file from build in Sigasi studio, the icon will be overlayed with a red forbidden entry icon forbidden icon in the upper left corner.

Editor View

The Editor View shows the content of files and allows you to edit files. It is a tabbed view so that multiple files can be opened for editing simultaneously. The currently selected file is the active file.

Outline View

The Outline View displays the contents of the active file, in terms of the HDL objects that it contains.

You can sort the elements in the outline alphabetically, by enabling the sort button sort icon.

You can also filter all concurrent signal assignments from the outline by enabling the Hide Signal Assignments button hide signal assignments. Double-click in the Outline View to navigate to the corresponding location in the editor.

If you enable the Link with Editor icon Link with Editor and you click an element in the Outline View, the corresponding code will be selected in the editor.

Quick Outline View

You can also press Ctrl+O to open the quick outline.

This is just the outline view in a popup, but it also allows you to filter the shown elements. This way, the quick outline can be used as a semantic Ctrl+F, making it very easy to find a declaration in your open editor.

[Only for Verilog]

Pressing Ctrl+O again, when the quick outline is open, will also show the inherited members between the members of the current file.

Hierarchy View

The Hierarchy View shows the design hierarchy starting at a selected top level object. To choose a top level, open a file and right-click on an architecture (or entity or configuration or module). Then click Set as Top Level. Alternatively, you can click the Set Top button in the Hierarchy View to open a hierarchy top level selection dialog. You can use the filter field to quickly search for a certain top level.

The Hierarchy View automatically refreshes itself when you save your design files. If you have a really large design this could slow you down. You can turn the automatic refresh on and off by toggling the refresh button refresh icon.

To highlight the current selection of the HDL editor in the Hierarchy View, enable the Link with Editor button Link with Editor. If the editor selection is part of the evaluated hierarchy tree, the corresponding hierarchy tree node will be selected.

The Hierarchy View also shows the generic and constants values of VHDL components in the hierarchy. The internal compiler computes the generics and constants, even if they are passed down through the hierarchy, and even if arithmetic operations are used to define new values. If the value cannot be computed for some reason, the Hierarchy View will report the value to be unknown.

When you double-click an object in the hierarchy, the Editor view is updated accordingly, possibly by displaying the contents of a different file.

Use the instantiations filter instantiations filter icon to hide everything except instantiations and structural statements.

You can launch a simulation with the launch icon button if you first set up a Launch simulator.

The Hierarchy View also offers an action Select required files, which selects all design files that are part of the current hierarchy, in the project explorer. This allows you to easily perform the same action on all files in the hierarchy. E.g. team commands, …

You can also export a CSV file with all dependencies of the selected element via the context menu: right-click and select Export Dependencies to CSV file.

Problems View

The Problems View shows problems (errors and warnings) related to your code. These problems were reported either by the internal compiler or by an external compiler tool. You can navigate to the source of the problem by double-clicking on a given problem. Problems can be sorted by clicking the column headers. The content of this view can be customized via the View Menu View Menu icon . Possible customizations are scope (workspace, project, selection), type, maximum number of problems, …

Libraries View

The Libraries View shows the library mapping of the design units in all projects. You can use it to navigate to a particular design unit in your project. When you double-click on a file, the file opens in the Editor view. If you right-click a file, you see the context menu which offers extra commands for setting libraries and for setting the top level.

If you enable the Link with Editor button Link with Editor, the Library View will be linked to the Editor View. Now, the active file in the Editor View will always be selected in the Library View.

Tasks View

It is common practice to add TODO and FIXME comments in your code. Sigasi Studio automatically scans your comments for TODO and FIXME tags and clearly highlights these comments with Task Tags. You can get a nice overview of all task markers in your workspace in the Task View (Window > Show View > Tasks).

You can configure extra tags in the Task Tag preference page: Preferences > Sigasi > VHDL > Task Tags

Bookmarks View

You can easily add bookmarks by right-clicking the line number where you want to add a bookmark. You can get an overview of all bookmarks in the Bookmarks View (Window > Show View > Others…).

The Bookmarks View can be used to delete bookmarks or navigate to the editor and other views.

Graphical Views

Block Diagram View

[Only in Sigasi Studio XPRT]

The Block Diagram View displays a graphical (block diagram) view of all architectures, modules, and their instantiations in your current VHDL or SystemVerilog editor. VHDL processes are also shown in the block diagram.

This viewer automatically updates while you are editing your code and gives a convenient way to visually inspect and navigate your code, even when your code is still unfinished or broken.

You can open the Block Diagram View by right-clicking in the editor and selecting Show In > Block Diagram. Alternatively, you can open the view via Window > Show View > Other… > Sigasi > Block Diagram.

You can also double-click blocks, ports, or wires to navigate to the corresponding HDL code. If you want to go into a block, you have to select it, right-click and click Open Entity Declaration, Open Architecture, or Open Module.

To find an object in the Block Diagram, you can navigate from your code to the Block Diagram. In your code, right-click a signal, port, process, or instantiation and select Show In > Block Diagram - just like when opening the Block Diagram View the first time. If the Block Diagram already is open, the corresponding element is highlighted and the Block Diagram View is centered on it.

You can export the Block Diagram View to an image with the save Save icon button. Both SVG and PNG are supported. Choose a *.svg filename for SVG export or a *.png filename for PNG export.

You can also export all block diagrams of an entire project at once: Click Project > Export… > Sigasi > Block Diagrams export and select your project. All SVGs will be created in diagrams/blockdiagrams/ in your project.

State Machine View

[Only in Sigasi Studio XPRT]

The State Machine View displays a graphical (bubble diagram) view of all state machines in your current VHDL or SystemVerilog editor. This viewer automatically updates while you are editing your code and gives a convenient way to visually inspect and navigate your code, even when your code is still unfinished or broken.

You can open the State Machine View by right-clicking in the editor and selecting Show In > State Machines. Alternatively, you can open the view via Window > Show View > Other… > Sigasi > State Machines.

If you have documented your state transitions (i.e. the assignments), the comments will be added as text to the transitions in the view.

You can also double-click nodes or transitions to navigate to the corresponding HDL code.

With the hide comments icon button, you can toggle the display of comments on edge labels.
With the hide conditions icon button, you can toggle the display of comments on edge labels. These labels show the code comments of the transition statements.
You also have to option to Zoom In, Zoom Out, or Zoom to Fit.

You can export state machines to an image with the save save icon button. Both SVG and PNG are supported. Choose a *.svg filename for SVG export or a *.png filename for PNG export.

You can also export all state machines of an entire project at once: Click Project > Export… > Sigasi > State Machine Diagrams export and select your project. All SVGs will be created in diagrams/statemachines/ in your project.

Check out our State Machine Viewer screencast for a demonstration.

Dependencies View

The Dependencies View visualizes the dependencies of your VHDL, SystemVerilog, or mixed language projects. This view shows the relationships between your source files and makes it easy to see top levels and important packages. The Dependencies View also makes it easy to detect orphaned files.

The view is automatically updated each time you save your files.

Dependencies View for a complete project with libraries and design units

The Dependencies View has the following options:

  • open folder icon show dependencies of the entire project. Uncheck to focus on the dependencies of the active editor only.
  • library icon Group design files per library
  • units icon Show design units inside design files. The design units are prefixed with an abbreviation of their kind (architecture, module, package, …" >}}

The Dependencies View can help you navigate too. Double-click a file name in the diagram to open the corresponding editor.

The Dependencies View can also be pinned. This prevents the diagram from changing when you switch editors.

You can export this diagram for documentation by clicking the save icon.

Documentation View

The Documentation View gives you a live preview of the automatic documentation Sigasi Studio can generate for your project.

Net Search View

[Only for VHDL]

With Net Search, you can find loads and drivers of a net. A net is defined as a signal or port and all other signals and ports that are directly connected to it. The loads are where you read the value of the net and the drivers are where you write to this net.

To find the entire net of a signal or port, place your cursor on the identifier and right-click. Now select Find Net. Alternatively, you can press CTRL+SHIFT+H.

The Net Search View will appear. For big designs, it might take a while before the results appear.

From the Net Search View, you can navigate to the VHDL code by double-clicking the search results.

VUnit View

[Only in Sigasi Studio XPRT]

The VUnit View allows you to get a quick overview of your VUnit test runs and to monitor ongoing test runs.

With the icons on top of the view, you can

  • Filter the output to show failures only
  • Rerun a test
  • Stop ongoing VUnit test runs
  • View the test run history

More information is available on the VUnit manual page.

Preprocessor View

[Only for Verilog]

In the Preprocessor View, you can preview the expanded text of Verilog macros. This view automatically synchronizes with the active editor. When you select text in the (System)Verilog editor, the expanded text will be highlighted in the Preprocessor View. This also works the other way: when you select text in the Preprocessor View, the corresponding, original source will be selected in the editor.

Class Hierarchy View

[Only in Sigasi Studio XPRT] ,[Only for SystemVerilog]

Class Hierarchy View

The Class Hierarchy View displays more information about the hierarchy of a class. It consists of a hierarchy tree and a list of the class members. To open the Class Hierarchy of a class, click the class name, right-click and select Open Class in Hierarchy (or press F4).

Open class in Hierarchy

Class Hierarchy Tree

The class hierarchy tree displays either the superclasses, subclasses, or both.

CommandDescription
hierarchy iconClass HierarchyDisplays all superclasses and subclasses.
superclass iconSuperclass HierarchyDisplays all superclasses and implemented interface classes.
subclass iconSubclass HierarchyDisplays all subclasses that extend or implement the selected (interface) class.
qualified class iconShow Qualified Class NamesShows the qualified name next to each class.

Member List

The member list shows all members of the class that is currently selected in the class hierarchy tree.

CommandDescription
inherited members iconShow Inherited MembersShows or hides all members inherited from superclasses.
sort iconSort By Defining ClassSorts members by the class in which they are defined.
hide iconHide FieldsHides all fields in the members list.

Console View

When Sigasi Studio launches external tools (e.g. external compiler, documentation generation,…) the output is logged to the Console View. This is a generic Eclipse view.

Different tools can open different consoles. You can switch between different consoles by clicking the icon console display-icon.

Minimap View

The Minimap View can be opened via Window > Show View > Other… and selecting General > Minimap. This is a generic Eclipse view.

This view is another way to help navigation through large files. It shows an overview of the entire active editor in a dedicated pane. The part that is visible in the editor is highlighted. The highlighted part of the Minimap View can be clicked and dragged to scroll through the Editor View.


[Back to top]

Sigasi Studio Editor

The Editor shows the content of files and allows you to edit files. It is a tabbed view such that multiple files can be opened simultaneously. The currently selected file is the active file.

VHDL and SystemVerilog Editor

The VHDL and SystemVerilog (or Verilog) editors are optimized to help you browse and edit VHDL and SystemVerilog code. Most browsing and editing features are similar for both languages.

Language-specific features are explained in “VHDL Specific” and “Verilog and SystemVerilog Specific”.

Code highlighting (syntax coloring)

Sigasi Studio colors your code to make the structure more clear. Unlike other tools, Sigasi Studio offers coloring based on the meaning of a word, rather than just the syntax.

Sigasi Studio supports both syntax highlighting and semantic highlighting. Syntax highlighting colors pieces of code according to the lexical class the code belongs to, such as a keyword or string. Semantic highlighting colors code according to its meaning. For example, a constant is shown in another color than a signal.

Code highlighting is fully configurable for a number of VHDL and Verilog and SystemVerilog syntax and semantic elements. Also, Color, background, style, and font can be customized. Learn more about configuring colors.

Rather than configuring every color yourself, you might want to have a look at the supported Light and Dark themes. To switch between themes, go to Window > Preferences > General > Appearance where you can choose a theme. While it is possible to install additional themes, only the Light and Dark themes are supported by Sigasi.

Type-time Syntax error reporting

Sigasi Studio marks VHDL and SystemVerilog syntax errors while you type. It will also report broken SystemVerilog preprocessor code.

Project exploration and navigation

Sigasi Studio offers powerful techniques to explore a file or project and navigate through it. This section covers: hovering, Occurrence Highlighting, Open Declaration, and Find References.

Occurrence Highlighting

If you click on an identifier, it is highlighted. In addition, all other occurrences of the identifier that refer to the same object are highlighted. Note that this occurrence highlighting is intelligent: it is not based on the identifier’s string value, but on the object that the identifier refers to.

You can turn occurrence highlighting on or off. Click the “Toggle Mark Occurrences” icon Mark Occurrences in the toolbar.

Find References

To look for occurrences of a given identifier in different files, place your cursor on the identifier and right-click. Now select Search References.

A search window will appear on the bottom of your workbench, displaying all occurrences of the selected identifier. You can easily navigate through all occurrences by clicking the Show Next Match arrow arrow_down and the Show Previous Match arrow arrow_up in the search result view. Note that all occurrences are highlighted and marked with a small arrow at the left border of the editor for easy recognition.

Open Declaration You can easily navigate to the declaration of any port, signal, entity, etc. Place the cursor on the identifier, right-click, and select Open Declaration. The editor immediately switches to the line that declares the object. Since this operation is so commonly used, it is assigned to the shortcut key F3.

Hyperlinks You can also navigate your code like a web browser by clicking hyperlinks. If you press and hold the Ctrl key, hyperlinks will appear in your editor. If you click the link (while holding the Ctrl key), you will navigate to the target of the link. Sigasi Studio offers the following links:

  • Link to Declaration: this has the same behavior as Open Declaration (F3)
  • Link to Matching Entity [VHDL]: this links a component declaration of an instantiation to the matching entity declaration. This also works for component generics and ports (Shift+F3)
  • Link to Matching Module [MIXED]: this links a component declaration of an instantiation to the matching Verilog module declaration. This also works for component generics and ports (Shift+F3). Modules that are instantiated as entity instantiations are also supported (label : entity work.verilogmodule port map (...);)
  • Link to Matching Architecture for entity declarations [VHDL]
  • Link to Matching When Clause [VHDL]: in finite state machines (FSMs) you can jump directly to the matching when part of your case statement from state transitions (Shift+F3)
  • Link to Open Declaration in Package Body [VHDL]: in packages you can jump directly to the matching declaration in the package body (Shift+F3). This also works in the opposite direction, Open Declaration in Package Body
  • Link to Open Declaration in Protected Type Body [VHDL]: in protected types you can jump directly to the matching declaration in the protected type body. This also works in the opposite direction, Open Declaration in Protected Type
  • Link to Include files in SystemVerilog sources (F3)
  • Link to Macro definition in SystemVerilog sources
  • URLs in comments

Hover

To learn more about the declaration of a given identifier, hold your mouse pointer over it. After a short time, a popup shows you the name and datatype of the signal. This technique is called hovering.

The hover pop-up can show different kinds of information:

  • datatype
  • comments: inline documentation written at the declaration (association rules)
  • value: the value of constants
  • errors or warnings: a message, if the given identifier has an error or warning associated with it
  • binary/decimal conversion: for hexadecimal, octal, or binary values, the decimal equivalent

Since Sigasi Studio 4.1 the hovers also offer extra links that make it easy to navigate to the declaration, find references …

Auto-complete and Content Assist

Sigasi Studio provides powerful autocompletion capabilities. This means that the tool can help you to complete identifiers and constructs as you are working on the code. Like other tools, the tool provides autocompletion based on the HDL language. However, it goes much further. It also provides autocompletion based on the design context. It can provide this additional level of intelligence as it knows all objects that have been declared in the design.

Autocompletion interface

Autocompletion may come from different sources, as will be discussed in the following sections. However, the user interface to initiate them is always the same. At any point as you are entering code, you can press Ctrl+Space and the tool will suggest appropriate autocompletion.

Based on the design context

Sigasi Studio uses its knowledge of the design to provide intelligent autocompletion that boosts your productivity tremendously.

The tool knows which objects are appropriate and which identifiers are visible at any given point in the code. As you start typing and ask for autocompletion, it will suggest the appropriate identifiers as autocompletion candidates.

Sigasi Studio provides help to autocomplete:

  • component declarations
  • component instantiations
  • entity instantiations
  • module instantiations
  • case statements (based on variables/signals with an enumeration type)
  • SystemVerilog preprocessor/macro directives ( `define, `ifndef, …)
  • SystemVerilog include paths ( `include "): triggering autocomplete between the double quotes will present a list of files and folders. If you select a folder, trigger autocomplete again to get completions in this folder.

Based on templates

Sigasi Studio can help you to declare VHDL and SystemVerilog objects, using autocompletion based on templates. Sigasi Studio comes preconfigured with templates for all common declarations and statements, including (for VHDL):

  • function, procedure
  • process
  • type: enum, file, range, array, record
  • signal, constant, variable
  • component
  • entity
  • architecture
  • entity/architecture pair
  • package/package body pair
  • and much more

Some autocompletions are templates that require further user input. In such a case, the editor goes into a special template editing mode after the autocompletion has been performed. You can use TAB to cycle through the items that have to be modified or completed. When done, you can press ENTER to return to the normal editing mode. The cursor will be placed at an appropriate position to continue working.

You can also configure your own templates. To edit or create templates, go to Window > Preferences > Sigasi > VHDL or Verilog/SystemVerilog > Templates. Here you get an overview of existing templates. You can create New… templates, Edit… existing templates, or remove templates.

In the template editor, you can type ${ and press Ctrl+Space to see a list of the available variables.

Templates can be exported and imported. This is useful for sharing templates with colleagues.

VHDL specific

A number of VHDL-specific autocompletes are available in Sigasi Studio.

Code formatting

Automated consistent code formatting makes code more readable and helps developers understand code, whether working on their own code or when cooperating with colleagues.

Read more about specifics on VHDL code formatting and Verilog and SystemVerilog code formatting.

Formatting Configuration

You can set preferences for Tabs or spaces under Window > Preferences > General > Editors > Text Editors.

Configure Spaces or Tabs

Here you can set the tab width in spaces and configure to Insert Spaces for Tabs. Whenever a tab is pressed, the corresponding number of spaces will be inserted instead. You can also opt to Remove multiple spaces on backspace/delete so that removing leading spaces follows the indentation levels.

Format code on save

You can configure Sigasi Studio to automatically format your (System)Verilog and VHDL files when you save your source files via Window > Preferences > Sigasi > [VHDL | Verilog/SystemVerilog], next check Enable code format on save.

Format files without opening them

[Only in Sigasi Studio XPRT]

You can format (System)Verilog and VHDL files without opening them in the editor.

  • You can format an entire project. Right-click the project in the Project Explorer and select Source > Format. Note that only files that are part of the build will be formatted.

  • You can format a selection of files. Select multiple files and/or folders in the Project Explorer and select Source > Format. Any selected file, part of the build or not, will be formatted. Any combination of resources can be formatted this way: multiple projects at a time, a project and a folder …

Other editor features

Code folding

If you work with large files, you might want to hide certain pieces of your code. This can be done with code folding. Certain constructs, such as if-statements or process-statements can be folded so that they use a single line in the editor view. You can do this by clicking the little "-" symbol next to the statement.

Code Folding

You can also enable/disable code folding and perform other actions by right-clicking in the gutter (the small column to the left of your code) and selecting Folding.

Configure Code Folding

Smart Caret positioning

Smart caret positioning allows you to easily jump between words within identifiers, no matter whether you use camelCase or snake_case, by using Ctrl+Left arrow and Ctrl+Right arrow.

Sigasi Studio 4.15 added the option to disable smart caret positioning in identifiers, both in VHDL and (System)Verilog. To change the setting, go to Window > Preferences > Verilog/SystemVerilog or Window > Preferences > VHDL where you can alter the selection of Smart caret positioning in identifiers.

Rename refactoring

Right-click on any identifier (VHDL or SystemVerilog) and select Refactor > Rename element (Alt+Shift+R) to change the name of the declaration and all its references. If you press Alt+Shift+R twice, you can preview the rename before applying it.

Full-screen view

Double-click on the editor tab to make it full-screen. You can also use Ctrl+M to achieve the same.

Block selection

Note: In other tools, this feature may be known as column editing or column select.

Block selection is an alternative to standard (paragraph) selection. Block selection mode differs from standard selection mode in that it allows to select rectangular regions, or to set the cursor over multiple lines. Block selection is ideal for selecting vertical regions, for example, a column of a table or all port names in a port map.

Block selection

To toggle between normal and block selection modes use Alt+Shift+A or press the Toggle Block Selection icon in the toolbar.

Structured selection

Structured Select enables you to select VHDL or SystemVerilog code, based on its syntactic structure.

Screencast: Select code, based on its structure

  • Shift+Alt+Up, expands the selection to the smallest syntax element that contains the current selection. You can then further expand the selection by invoking the action again.
  • Shift+Alt+Down, contracts the current selection to the nested syntax expression that still contains the current cursor position. You can then further contract the selection by invoking the action again.
  • Shift+Alt+Left, adds the syntax element left of the current selection to the selection. You can then further expand the selection by invoking the action again. You can also expand the selection in the other direction with Shift+Alt+Right

Add parentheses or create a string

When you select a region and press ( or [, the selected region is enclosed with the matching closing parentheses, ) or ].

When you select some text and press ", the selected text will be transformed into a string. This works for both regular and multi-line strings.

This behavior can be disabled by unchecking Enclose selected region when typing parentheses or quotes in Window > Preferences > Sigasi > VHDL.

Show whitespace

You can turn show or hide whitespace markers by clicking the Show Whitespace Characters icon Show Whitespace Characters in the toolbar.

Move and Duplicate lines

You can easily move lines up and down by pressing: Alt+Up and Alt+Down.

You can duplicate your current line, or the lines of the current selection by pressing: Ctrl+Alt+Down.

Configure key bindings

See Keyboard Shortcuts

Emacs/VI emulation mode

See VI and Emacs

Remove Trailing Whitespace

The action to remove trailing whitespace is hidden by default. You can access it by pressing Ctrl+3, typing RTW, and then selecting the correct action. Alternatively, you can bind this action to Keyboard Shortcuts of your preference. This action is being executed on the saved file, not in the editor. So before using this action, you have to make sure your file is saved.

Customize color preferences

There are several ways to customize color preferences in Sigasi Studio.

  • Choose the Eclipse Theme in the Window > Preferences > General > Appearance preferences menu.
    • Edit Eclipse Colors and Fonts setting in the Colors and Fonts sub-menu.
  • Change color setting for different text editor features in Window > Preferences > General > Editors > Text Editors
    • Annotation colors can be configured in the Annotations sub-menu.
    • Highlighting colors for differences can be configured in the Quick Diff sub-menu.
  • Syntax coloring for Verilog/SystemVerilog can be changed in the Window > Preferences > Sigasi > Verilog/SystemVerilog > Syntax Coloring preferences menu.
  • Syntax coloring for VHDL can be changed in the Window > Preferences > Sigasi > VHDL > Syntax Coloring preferences menu.

Multiple Screen Support

You can right-click the title tab of any view and select Detach to move the view into a separate window that can be dragged to another screen. Alternatively, you can drag a view out of the current window to create a new window from it.

Once multiple windows are available, views can be dragged between screens.

Resetting the Sigasi Studio perspective will move all views into a single window.

See also this FAQ item.

Split Editor

Editor Menu

The Editor View can be split or duplicated in independent viewports that access the same file buffer. There are 3 ways to split the Editor View.

  • Horizontal Split Horizontal Split shows 2 viewports on top of each other.
  • Vertical Split Vertical Split shows 2 viewports next to each other.
  • Clone to a new Editor View. This new Editor View can be detached so that the same file buffer can be viewed on multiple displays.

To split the editor view, go to Window > Editor and select the desired action. There are Keyboard Shortcuts to toggle the Horizontal Split (Ctrl+_) and the Vertical Split (Ctrl+{).

There can only be a single horizontal or vertical split within an Editor View. Multiple Editor Views can be cloned and re-arranged to obtain a custom layout with many views on the same file buffer.

Side-by-side Diff

  • Previous versions (local history or version control)
  • Comparing two files

Opening project files

The default way to open files in the VHDL and SystemVerilog editor is to double-click the files in the Project Explorer. But there are more methods to open files in your projects.

Open Resource

When you press Ctrl+Shift+R the Open Resource dialog opens. In this dialog, you can type a name or pattern to open a specific file name.

Open Design Unit

When you press Ctrl+Shift+D the Open Design Unit dialog opens. In this dialog, you can type a name or pattern to open a specific VHDL or SystemVerilog design unit name.

Open Design Unit Dialog

Note that excluded design files do not appear in this list.

VHDL Specific

In addition to the powerful features of an Eclipse editor, the VHDL editor that comes with Sigasi Studio supports a number of advanced editing features which are specifically useful for VHDL editing. These are described in this chapter.

Code highlighting

Highlighting Classes for VHDL:

  • Syntax : Comment, Keyword, Number, String, Task tag
  • Semantic : Constant, Port, Signal, Type, Variable, Attribute, Function/Procedure, Labels

VHDL specific autocompletes

Instantiating an entity

Note: In other tools, this feature may be known as paste as instantiation or port translation.

Sigasi Studio knows all entities in the design and their interfaces, and can therefore automate much of the instantiation process. At the point in the code where you normally enter the entity name, you can use autocompletion instead to suggest a list of possible entities. Upon selection, the tool will complete the instantiation with a generic map and a port map with named associations. As an initial suggestion, each actual parameter will have the same name as its formal parameter. Of course, the actual parameter names need to be reviewed and edited by the user. Therefore, the editor will go into template editing mode after the autocompletion.

Instantiating a component is similar to instantiating an entity. Note that components will only be shown if they are visible in the current scope.

Declaring a component

Note: In other tools, this feature may be known as paste as component or port translation.

If you want to use instantiation based on a component (as opposed to direct instantiation) you need to associate an entity with a component. Sigasi Studio can automatically declare a component for an existing entity. At the point where you normally enter the component name, you can use autocompletion instead to show the list of available entities. Upon selection, the tool will automatically complete the component declaration.

Type Conversion

In VHDL design you need to do a lot of type conversions. Sigasi Studio’s autocomplete functionality can help you with those. Put a dot (.) after the element you want to convert, and the autocomplete suggestions will appear. The conversion functions have descriptions like “convert type” and “convert to …”.

Stuttering

Stuttering is an editing technique popularized by Emacs, that lets you type certain things really fast. Stuttering means that you tap a certain key twice and it expands to something more complex. For example, press the period key . twice, and the editor will expand it to a right arrow =>. Stuttering works like double-clicking: if you type keys slowly, the stuttering mechanism will not be triggered.

The following stuttering keys are available:

KeysEffect
,,<=
..=>
;;:=

Stuttering can be disabled or enabled through the Enable stuttering option in the Window > Preferences > Sigasi > VHDL menu.

Smart Indentation

When you press enter, Sigasi Studio automatically adjusts the indentation of the current and the new line. Depending on the content of the preceding line, Sigasi Studio will automatically increase or decrease the indentation level. E.g. an extra indent after an if-statement and removal of an indent for the matching else-clause.

You can enable/disable this feature via Window > Preferences > Sigasi > VHDL by toggling the “Enter adjusts indentation on current and next line” setting.

Tabs vs. spaces: This features inserts tabs characters or spaces, according to your preferences.

See also:

VHDL code formatting

Press Ctrl+Shift+F to format your current VHDL file.

This includes:

  • indentation
  • vertical alignment of certain symbols like “<=”
  • wrapping lines that are too long

Context-based

Sigasi Studio’s formatter is context-based and tries to respect the author’s style. So depending on the original source style, the formatter might make different choices.

One example is the decision to format a conditional signal assignment on one, or multiple lines. Sigasi Studio makes this decision based on the position of the first else keyword. If you put the else keyword on the first line, the formatter will put everything on one line. If you put the else keyword on a new line, the formatter will use multiple lines for the assignment.

  demo <= (others => '0') when enable = '1'
    else (others => '1') when input = '1' -- else on new line
    else (others => 'X');

Note about broken code: If your VHDL source file contains syntactical errors, the formatter can not always figure out appropriate formatting. For this reason, the formatter is programmed to stop applying (whitespace) changes when unsupported syntax errors are encountered.

Configuration

You can set your preferences for Tabs or spaces under Window > Preferences > General > Editors > Text Editors.

VHDL-specific code formatting can be configured at Window > Preferences > Sigasi > VHDL > Formatting. Configurable settings currently include:

  • Preserve newlines: this option configures the formatter to not add or remove newlines in your code.
  • Vertical alignment: this option configures the formatter to vertically align consecutive declarations and statements.
  • Lowercase/Uppercase keywords: when this option is set to UPPERCASE the formatter will convert all VHDL keywords to uppercase. When this option is set to lowercase, the keywords will be converted to lowercase. When this option is set to ignore, the case of keywords won’t be changed by the formatter. (Without a Sigasi Studio XL license, keywords are not changed by the formatter).
  • Alignment column for trailing comments: this setting configures the column Sigasi Studio uses to align trailing comments (default is column 40)

Correct indentation only

Sigasi Studio can also correct the indentation of your code without making any other changes. Inside a VHDL editor, open the context menu and click Source > Correct Indentation, or hit Ctrl+I. This only changes whitespace at the start of your lines.

If you select code first, only the code in the selection will be indented.

Disable formatting in defined regions

You can disable the formatter for defined regions in your VHDL source files by enclosing them with off and on tags:

  • off tag: -- @formatter:off
  • on tag: -- @formatter:on

VHDL 2019 tool directives

Sigasi Studio 4.16 introduced VHDL 2019 tool directives, which are a simplified version of the preprocessor found in SystemVerilog or the C family of languages.

Tool directives allow to conditionally enable code based on tool type, debug mode, or really any other custom variable.

You can edit the defined tool directives by right-clicking your project and then going to Properties > VHDL Conditional Variables.

Check out the video to see directives in action.

Verilog and SystemVerilog Specific

In addition to the powerful features of an Eclipse editor, the Verilog and SystemVerilog editor that comes with Sigasi Studio supports a number of advanced editing features which are specifically useful for SystemVerilog editing. These are described in this chapter.

Code highlighting

Highlighting Classes for Verilog and SystemVerilog:

  • Syntax : Comment, Keyword, Number, String, Task tag, Operator
  • Semantic : Assignment, Class, Covergroup, Macro, Enum, Function, Localparam, Module, Net/Wire, Parameter, Port, Type

Include paths and initial preprocessor definitions

The fastest way to add an include path is to run the Quick Fix on `include errors in the editor. You can configure the include paths of your SystemVerilog projects in the Verilog Preprocessor property page. Right-click your project and select Properties > Verilog Preprocessor.
Here you can Add and Remove include paths using the buttons on the right. You can also move the order of the include paths using the Up and Down buttons. The Import... and Export... buttons can be used to transfer a semicolon-separated (;) list of include paths from and to the clipboard.

In the Initial preprocessor definitions field, you can configure definitions that are set before other files in the project are processed. This allows you to, for example, set global defines without an explicit include statement.

When you hover over a SystemVerilog preprocessor directive (e.g. include ...), Sigasi Studio shows the preprocessed text. You can find a convenient link to open the Preprocessor View at the bottom of this hover.

Ctrl+Click on `defines (or F3) will lead you to the corresponding declaration. Autocomplete will also offer you a list of all visible `defines.

In the Preprocessor View, you can preview the expanded version of your preprocessed SystemVerilog source files.

Verilog version

You can configure the Verilog version via Window > Preferences > Sigasi > Verilog/SystemVerilog and select whether *.v files are treated as Verilog or SystemVerilog. *.sv files are always treated as SystemVerilog.

Smart Indentation

When you press enter, Sigasi Studio automatically adjusts the indentation of the current and the new line. Depending on the content of the preceding line, Sigasi Studio will automatically increase or decrease the indentation level. E.g. an extra indent after a module and the removal of an indent for the matching endmodule.

You can enable/disable this feature via Window > Preferences > Sigasi > Verilog/SystemVerilog by toggling the “Enter adjusts indentation on current and next line” setting.

Tabs vs. spaces: This features inserts tabs characters or spaces, according to your preferences.

See also:

Verilog and SystemVerilog code formatting

Press Ctrl+Shift+F to format your current Verilog or SystemVerilog file.

The default formatter implementation corrects indentation only.

Since Sigasi Studio 4.15, Sigasi ships with Verible built-in. Verible is an ambitious SystemVerilog formatter that is agnostic to macro invocations and includes and therefore produces a consistent formatting result even in heavily preprocessed code.

You can enable the Verible formatter for your installation by going to Window > Preferences > Sigasi > Verilog/SystemVerilog > Formatting. Under Select formatter, you can choose between the default Sigasi formatter which corrects indentation, and using the Verible formatter.

Sigasi ships with a recent Verible version by default. If you’d rather run your own Verible installation, this can be achieved in Window > Preferences > Sigasi > Verilog/SystemVerilog > Formatting > Verible. To select your own Verible binary instead of the one that comes with Sigasi, select the Use external Verible formatter instead of bundled one: option and configure the Verible installation path: option.

This page also allows you to customize the Verible formatting rules, both for the built-in and the external Verible binaries, by pressing the Edit… button. For maximal compatibility, you need to make sure the Eclipse setting to Insert spaces for tabs is enabled and that the Displayed tab width is matching the Verible configuration.

In the Verible configuration page, configurations are grouped in the following tabs.

  • Indents and Wrapping
  • Ports and Parameters
  • Types
  • Statements and Expressions

If you want to undo your changes, you can use the Restore Defaults button, either per tab or for the entire dialog. After applying your configuration changes, press the OK button.

To see this in action, you can have a look at our screencast.
The Verible website and README contain more information.


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Opening Files

Opening Files from the Command Line

You can call Sigasi Studio from the command line to open files. Just run sigasi yourFile.vhd. You can also drag and drop files on the Sigasi Studio icon to open them.

You can specify a linenumber by appending +yourLineNumber to the command line. For example: sigasi test.vhd +10 will open test.vhd at line 10.

You can also specify the project location with the -p <project path> parameter. If the specified project was not open in the workspace yet, this will import and open the project in the workspace.

Note that the VHDL file you specify on the command line has to be in an open Sigasi project to enjoy all of Sigasi Studio’s powerful editing and navigation features. If the file you open from the command line is not in a Sigasi Studio project, Sigasi Studio opens the file as an external file. This is nevertheless really handy for quick edits.

This feature enables you to configure Sigasi Studio as default editor for other EDA tools.

Note You could get a firewall warning when you start Sigasi Studio because Sigasi Studio opens and listens to a port (4444 by default). This is necessary for the communication between the running Sigasi Studio instance and the command line executable. Configure your firewall to allow Sigasi Studio access for opening this port.
Update Since Sigasi Studio 4.17.2, the listener no longer listens to port 4444. A random free port will be used, one per user on multi-user systems.

Eclipse Plugin

Eclipse plugin users can also use this feature but need to specify a few more command line options. You have to type eclipse -application com.sigasi.runner.open instead of sigasi. For example: eclipse -application com.sigasi.runner.open test.vhd +10 will open test.vhd at line 10.

Other command line options

You can add some extra parameters to Sigasi Studio to modify the behavior.

  • -help : show simple command line usage information
  • -data <location> : specifies the workspace location
  • -noSplash : do not show the splash screen at startup
  • -consoleLog : log all debug information in the console (in addition to the regular log file)
  • -refresh : force refresh of workspace
  • -showLocation : show workspace location in title bar
  • -application org.eclipse.ui.ide.workbench : use the default Eclipse workbench launcher instead of the Sigasi Studio workbench launcher. This avoids conflicts on port 4444 when running Sigasi Studio with multiple users on the same server. Refer to the setup page for more information.
  • --launcher.openFile <somepath> : open the Import Projects dialog to import a new or existing project into the workspace
  • -Dcom.sigasi.hdt.disableAutomaticTutorial : suppress the creation of the tutorial projects in empty workspaces.
  • -Dswt.chromium.path=/home/user/blub : extract the Chromium binaries in blub

External Files

You can edit VHDL files without setting up a project. When a file that doesn’t belong to a project is opened in Sigasi Studio, this file is called an external file and it will be opened in single file mode.

Single file mode is a limited environment in which not all Sigasi Studio features are available. Navigation only works within a file. For that reason missing declaration are not flagged as errors.

There are several ways to open VHDL files:

  • Drag the files to the editor window.
  • Open the file from the command line
  • Drag the files to the Sigasi Studio icon
  • Click File > Open File…

If the file belongs to a project, Sigasi Studio will open the file as part of that project. If not Sigasi Studio opens the file as external file.

In general, if you want to benefit from all of the Sigasi Studio features, you should set up a proper project.

Setting up Sigasi Studio as Default Editor

Windows

To configure Sigasi Studio as default VHDL editor in Windows:

  • Find a VHDL file in the File Explorer
  • Right-click and select Open with > Choose default program…
  • Next click the Browse button and select the Sigasi Studio executable (<path to Sigasi Studio>/sigasi.exe)
  • Next Sigasi Studio will appear in the list of programs
  • Verify that “Always use the selected program to open this kind of file” is enabled
  • Confirm with OK

Repeat this procedure for *.vhd files and for *.vhdl files.

Linux

KDE

  • Find a VHDL file in Dolpin or Konqueror
  • Right-click and select Open with > Other…
  • Enter the path of the Sigasi Studio executable (or use the browse button)
  • Click the Remember application association for this type of file so that all other VHDL files will also get opened with Sigasi Studio.
  • Click OK
Sigasi Studio as default editor in KDE

Gnome

  • Find a VHDL file in Nautilus
  • Right-click and select Open with > Other Application…
  • In Use a custom command: Enter the path of the Sigasi Studio executable (or use the browse button)
  • Click the Remember this appliation for “VHDL document” files so that all other VHDL files will also get opened with Sigasi Studio.
  • Click Open
Sigasi Studio as default editor in Gnome

MacOS

Please note that from version 5.0 onwards, Sigasi Studio is no longer supported on MacOS.

When I double-click a VHDL file, I want it to open with my favorite VHDL editor. Sigasi Studio, obviously.

Here is how to set this up in MacOS:

  • Find a VHDL file in the Finder
  • Right-click and select Get Info
  • Select Open with > Other… and find your Sigasi Studio application
  • Click Change All… so that all other VHDL files will also get opened with Sigasi Studio.

Repeat this procedure for *.vhd files and for *.vhdl files.

Setting the default application for VHDL files

Intel Quartus

In Intel Quartus, open the preferences page in Tools > Options > General > Preferred Text Editor.

Configuring Sigasi Studio as default VHDL editor in Intel Quartus

As command-line options, you should have %f +%l -p %p. Optionally you could add -noSplash to skip the splash dialog.

AMD/Xilinx Vivado

You can configure Sigasi Studio to be the preferred editor for AMD/Xilinx Vivado.

  1. In AMD/Xilinx Vivado, click Tools > Settings…
  2. Open the Tool Settings > Text Editor tab
  3. Locate the Current Editor drop down menu and instead of ‘Vivado Text Editor (default)’ select ‘Custom Editor…
  4. If needed click the button and in the pop-up dialog enter: <path to Sigasi Studio>/sigasi.exe [file name] +[line number]
  5. Click OK to close the dialog and OK to close the Settings window.

Configuring Sigasi Studio as default editor in AMD/Xilinx Vivado menu
Configuring Sigasi Studio as default editor in AMD/Xilinx Vivado

Extra steps on Linux

If your log file contains warnings about LD_LIBRARY_PATH being set to an incompatible value or if you get an error telling the JVM terminated, you can correct this by making sure LD_LIBRARY_PATH and (optionally) LD_PRELOAD are empty when launching Sigasi Studio. Do this by e.g. creating a script to launch Sigasi Studio and call that script from within the Vivado Text Editor settings.

#!/usr/bin/env bash

SIGASILOCATION="/path/to/sigasi"

LD_LIBRARY_PATH="" LD_PRELOAD="" "$SIGASILOCATION/sigasi" "$@"

Extra steps for the Sigasi Studio plugin on Windows

If you use the Sigasi Studio Eclipse plugin on Windows, you might need to take some extra steps before you can open files from Vivado in Sigasi Studio.

Make sure to close Eclipse before making the changes below.

  • In your Eclipse installation

    1. In eclipse.ini remove these 2 lines
      --launcher.defaultAction
      openFile
      
    2. In configuration/config.ini
      • replace osgi.instance.area.default=... with osgi.instance.area=@nodefault - note the removal of the .default suffix
      • replace eclipse.application=.... with eclipse.application=com.sigasi.runner.open
  • In Vivado configure the custom editor with the following setting C:\....\eclipse.exe [file name] +[line number]

The first time you might need to pick a workspace and enable the use this as default and do not ask again option.

AMD/Xilinx ISE

To configure Sigasi Studio as default VHDL editor in AMD/Xilinx ISE:

  1. In AMD/Xilinx ISE, Click Edit > Preferences and ISE General > Editors
  2. Select Custom instead of ISE Text Editor
  3. If Sigasi Studio is on your path enter sigasi.exe $1 +$2 (Windows) or sigasi $1 +$2 (Linux). If Sigasi Studio is not on your path, use the absolute path instead. If there are spaces in this path, you need to enclose the path in curly braces . For example:c:\\My\ Applications\sigasi\sigasi.exe $1 +$2.
Configuring Sigasi Studio as default VHDL editor in AMD/Xilinx ISE

If you now open any VHDL file in AMD/Xilinx ISE, Sigasi Studio will automatically open the selected file.

You can find more info on configuring AMD/Xilinx ISE to work with external editors in the AMD/Xilinx documentation.

HDL Designer

To configure Sigasi Studio as external editor in HDL Designer:

  1. In HDL Designer, click Options > Main
  2. Click the Text tab
    Main Settings Text 1
  3. Press the Setup… button in the Editor section to open the Editor Command Setup dialog.
  4. Fill the Name, Command and Arguments sections as shown.
    Editor Command Setup 1
  5. Click the Add button to add Sigasi Studio to the list of available editors.
    Editor Command Setup 2
  6. Press OK to close the dialog.
  7. Press the Setup button in the HDL Viewer section and repeat this procedure from step 4.
    Editor Command Setup 3
  8. You now can select the Sigasi entry in the list box for the Editor and HDL Viewer sections.
    Main Settings Text 2
  9. From now on you can double click on a file or a line in a file - for example by selecting an architecture or an entity - and Sigasi Studio will open the file at the correct location.

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Linting and Quick Fixes

In addition to syntax validation, Sigasi Studio also checks your code for semantic problems (Linting, or Linter checks). Some of these problems can be automatically resolved with Quick Fixes. Both syntax checking and linting happen at type-time: new markers appear as you are typing your code.

Linting

VHDL code Lint is defined as code that is strictly correct according to the language definition, but still suspicious or problematic. Sigasi Studio has a built-in linter, which provides info about code lint in the design.

In addition to code linting, Sigasi Studio can also check that file headers and symbol names (entities, signals, variables…) follow certain patterns. This is discussed under naming conventions.

Marker Icons

  • marks an info message that can be resolved automatically with a Quick Fix.
  • marks an info message.
  • marks a warning that can be resolved automatically with a Quick Fix.
  • marks a warning that cannot be resolved automatically.
  • marks an error that can be resolved automatically with a Quick Fix.
  • marks an error that cannot be resolved automatically.

Configuring the Severity Level

The Sigasi Studio VHDL linter has reasonable defaults for the severity level of reported lint problems. However, the severity level of certain classes of linting rules is configurable for additional flexibility. The configuration interface to configure severities for the entire workspace is available through:

  • For (System)Verilog rules: Window > Preferences > Sigasi > (System)Verilog > Errors/Warnings
  • For VHDL rules: Window > Preferences > Sigasi > VHDL > Errors/Warnings
Configuring the severity of Sigasi Studio linting checks

You can also configure the severity level per project.

Suppressing warnings

Specific warnings can be suppressed in your code by adding a @suppress comment (-- @suppress for VHDL, // @suppress for SystemVerilog), on the same line as the warning.

You can limit the suppression to a specific warning by putting a prefix of the warning message between quotes after @suppress. Sigasi also recommends adding a reason why the warning was suppressed by adding an extra comment after @suppress:

<line with warning> // @suppress "Warning message prefix" Reason why warning is suppressed

Since Sigasi Studio 4.2 the @suppress comment also suppresses Errors. Since Sigasi Studio 4.3 warnings have a quickfix to automatically add the @suppress comment with a matching warning message prefix.

No Linting for Common Libraries

Common Libraries are considered to be production ready libraries. Linting is skipped for all files in the Common Libraries folder.

Naming conventions

Sigasi Studio can check whether all sorts of names in the design - entities, instances, modules, signals, variables… - follow particular patterns. This may help designers to follow their company’s or team’s coding rules. For example, coding rules may prescribe that signal names must have a s_ prefix, that generics names must be written in capitals, or that variable names must use CamelCase. Empty rules (which is the default) means that the particular rule is not checked.

In addition, Sigasi Studio can also check for file header comments, e.g. whether a copyright notice or disclaimer have been included.

Workspace wide naming conventions settings are accessed via
Window > Preferences > Sigasi > Verilog/SystemVerilog > Naming Conventions
Window > Preferences > Sigasi > VHDL > Naming Conventions

At the top, you can set the severity of naming convention and file header comment non-conformities. Below, you can enter the validation patterns. Patterns use the Java regular expressions syntax. Information on Java regular expressions is available through the link above the severity settings. Note that names are not validated if the corresponding validation pattern is empty.

Configuring naming conventions

You can also configure naming conventions per project, or even per file or folder. Documentation on how to do that is here.

Quick Fixes

Some of the VHDL lint problems can be automatically resolved with Quick Fixes. These problems have markers annotated with a lightbulb icon (like ). To trigger a Quick Fix, click the problem marker or press Ctrl+1 and select the Quick Fix.

Language specific code rules

The currently available linting rules are described in detail on the following pages.

Project specific Linting settings

Severity of Linting checks

Sigasi Studio offers 2 ways of configuring the severity of linting checks.

  • For the entire workspace, through the Window > Preferences dialog as described above.
  • You can override these setting by creating a settings file for your projects.
    In each project, you can override the coding rules settings. You can override rules for the entire project, for folders in the project, or for individual files.

Errors/Warnings property page

To configure the severity level, right click the project (or file or folder) in the Project Explorer and select Properties > VHDL Errors/Warnings or Properties > SystemVerilog Errors/Warnings.

Configure linting severity per project

On the top of the dialog, select Enable project specific settings to activate the severity level on a project base. Enabling this setting will override any settings specified at the workspace level. For each of the available ID’s, you can choose from a drop-down list or you can set all severities at once using the drop-down list on top.

Note that choosing the default setting does not inherit from the workspace settings. It will apply the Sigasi built-in default for a linting rule.

Project settings are stored in this settings file:

    ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs

You can search for a specific rule, by using the search field at the top of the property page.

Search for a specific rule

Manual configuration

To configure the severity of validations, add a line for each validation:

    ${validation id}/severity/${path}=${severity}

Where ${validation id} can be

  • the number of the validation ID (e.g. 140)
  • all to specify all validation ids in one rule

Validation ID numbers are listed in the list of VHDL code rules, the list of (System)Verilog code rules and can also be found in the Project Properties under VHDL Errors/Warnings.

Where ${path} can be:

  • <project> (literally, with brackets!) to set the severity of the entire project
  • /path/to/folder to set the severity of an entire folder
  • /path/to/file.vhd to set the severity of a specific file

Where ${severity} can be:

  • ERROR
  • WARNING
  • INFO
  • IGNORE

Whitespace must be escaped with a back slash (\). You can add comments with #.

Examples:

    72/severity/<project>=IGNORE
    72/severity//Folder\ name/Extra\ folder=INFO
    72/severity//test/top.vhd=WARNING
    all/severity/<project>=IGNORE

Naming Conventions per project

While Naming Conventions and the Header Comment check can be configured globally for a workspace, they can also be defined per project, per folder or per file.

If you only want to change the severity of naming convention and/or file header checks for an entire project, you can change them through the dialog in Sigasi Studio:
Project > Properties > Verilog Errors/Warnings (look for ID 92 and 188)
Project > Properties > VHDL Errors/Warnings (look for ID 2 and 22)

Other project specific naming convention and/or file header check settings can be configured in the configuration files.

The project-specific Naming Conventions and Header Comment are stored in this settings file for VHDL related settings:

    ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs

For (System)Verilog related settings, this settings file is used:

    ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs

The validation ID for Naming Conventions is 92. The validation ID for the Header Comment is 188.

Syntax for Naming conventions

All lines that configure Naming Conventions should start with 92 and are of this format:

    92/params/${identifier}/${path}=${convention}

Valid ${identifier} values are:

    architecture_name
    configuration_name
    constant_name
    entity_name
    generate_statement_name
    generic_name
    instantiation_statement_name
    label
    package_name
    port_name
    process_statement_name
    signal_name
    type_name
    variable_name

Naming Conventions can be restricted to a specific file or folder using ${path}. Possible values are:

  • <project> (literally, with brackets!) to set Naming Conventions for the entire project
  • the folder name to which the Naming Convention should apply
  • the full path of the file to which the Naming Convention should apply

The pattern that defines the Naming Convention is set in ${convention}. Patterns are configured with regex syntax.

Naming Conventions for a project and setting the severity of the linting checks are configured in the same settings file.

Syntax for Header Comment

Lines that configure the Header Comment should start with 188 and are of this format:

    188/params/comment_header/${path}=${convention}

The meaning of ${path} and ${convention} is equal to the definitions for Naming Conventions.

Examples:

    92/severity/<project>=INFO
    92/params/constant_name/<project>=c_.*
    92/params/entity_name/my_folder=e_([A-Z_0-9])*
    188/severity/<project>=WARNING
    188/params/comment_header//<project>=-- Project specific header comment\r?\n-- Second line
    188/params/comment_header//my_folder=-- Folder specific header comment

Note that to use \R in the configuration file the \ needs to be escaped. So you’ll need to put \\R in the configuration file.

Errors in the patterns will be reported in the log file: Help > Open Log.


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Verilog and SystemVerilog Linting

List of Verilog and SystemVerilog code rules

The table below lists the Verilog and SystemVerilog code rules that can be checked automatically by Sigasi Studio. The availability of code rules depends on the license requirements.

ST code rules

ST code rules are available for all licenses including Sigasi Studio Starter .

DescriptionID
File encoding differences between including and included files
Named and positional port connections cannot be mixed5
The packed keyword is required in packed structs and unions6
The for loop statement misses mandatory part (Verilog)9
Parameter port list cannot be empty11
No semicolon expected at this point (Verilog)12
Verilog disallows empty assignments of ordered parameters (Verilog)13
Named and positional parameter overrides cannot be mixed25
Only one default member expression is allowed per assignment pattern29
Only variable output ports can have a default value in non-ANSI notation33
Only input or variable output ports can have a default value in ANSI notation34
Duplicate formal item within the instantiated unit37
Excessive number of actuals in ordered notation39
Timing controls are not allowed in functions46
Net data types must be 4-state50
Net data types integral51
Invalid package item55
Unexpected preprocessor directive inside design elements57
Non-packed member in packed structure59
Illegal type in untagged union60
Illegal class member access61
Declaration not found71
Attempted implicit declaration with default nettype none73
Invalid enumeration element range format74
Range of enumeration element is too large75
Invalid construct76
Invalid randomize argument77
Not a value expression78
Type not assignment compatible79
Constraint class scope missing80
Constraint class with packed dimensions81
Ambiguous reference93
Duplicate declaration95

XL code rules

XL code rules require a Sigasi Studio XL or Sigasi Studio XPRT license.

DescriptionID
Empty loops and conditional branches1
Check naming conventions2
Warning with lightbulb Disallow reg datatype3
The module name is a keyword in VHDL and may cause problems in mixed language projects7
Case statement does not cover all cases8
Function prototype has implicit return type10
Info with lightbulb Implicit subprogram port direction14
Default clause has to be the last item in a case statement15
Case statement has multiple default clauses, but only one default clause is allowed16
File name does not match design unit17
File contains multiple design units18
Parameters must have a default value19
Verilog code line too long20
Tabs are not allowed21
File header comment does not match required pattern22
Named port connections have to be used for all instances with many ports24
Named parameter overrides have to be used for all instantiations with many parameters26
No event control at the top of always construct27
Default member must be last in assignment pattern28
Overwritten type key in assignment pattern30
Duplicate member key in structure assignment pattern31
Mixed named and ordered notation in assignment pattern32
Register initialization in declarations35
Formal item not found within the instantiated unit36
Missing actuals for formals that have no default value38
Default clause missing from case statement40
Non-blocking assignments are not allowed in functions41
Consecutive underscores in unit / port identifier42
Underscores at end of unit / port identifier43
Report encrypted regions44
Multiple statements per line47
Missing bit width for parameters wider than 32 bits48
Trailing comma is not recommended52
Empty parameter not allowed53
Empty parameter overrides not allowed54
Named connections are not allowed with blank ports56
Regular expressions (RE2/J) compatibility check58
Overridden method signature mismatch62-68
Local parameter has to be initialized69
Local parameter cannot be overridden70
Out-of-bound method signature mismatch82-92

Deprecated code rules

Deprecated code rules were used by Sigasi Studio at some point, but they’ve been removed or superseded in the most recent version.

DescriptionReasonID
A Verilog net type keyword cannot be followed directly by the reg keywordSuperseded by a syntax error4

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VHDL Linting

List of VHDL code rules

The table below lists the VHDL code rules that can be checked automatically by Sigasi Studio. The availability of code rules depends on the license requirements.

ST code rules

ST code rules are available for all licenses including Sigasi Studio Starter .

DescriptionID
Warning with lightbulb Declaration could not be found
Duplicate declarations
Warning with lightbulb Signal/variable assignment operator
Warning with lightbulb Case statement does not cover all choices
Warning with lightbulb Missing enumeration literal in case statements
Instantiation statement validation
Library validation
Subprograms in packages (e.g. function body in a package, rather than in the package body)
Missing return statement in function bodies
Warning with lightbulb Correct attribute entity class in attribute specifications
Warning with lightbulb C-style equality and inequality operator (= and /= vs == and !=)
Warning with lightbulb VHDL 2008 features in VHDL 93 mode (Learn about choosing your VHDL version)
Warning with lightbulb Port/Generic lists cannot be terminated with a ‘;’
Warning with lightbulb Port/Generic maps cannot be terminated with a ‘,’
Loop variables cannot be assigned
Declaration not found

XL code rules

XL code rules require a Sigasi Studio XL or Sigasi Studio XPRT license.

DescriptionID
Null range: The left argument is strictly larger than the right1
Warning with lightbulb Deprecated IEEE packages8
Case alternative contains redundant choices12
Case statement contains all choices explicitly. You can safely remove the redundant ‘others’13
Infinite loop. Loop is missing a wait20
Null range: The left argument is strictly smaller than the right26
Warning with lightbulb Non-standard packages37
Warning with lightbulb A process must either have a sensitivity list or contain one or more wait statements38
There has to be a whitespace before physical units47
Unbound component instantiations48
Superfluous library clause49
Warning with lightbulb Library is not available Configure Altera, AMD/Xilinx, ModelSim and VUnit libraries50
Warning with lightbulb Find unused declarations55
Bitstrings may only contain std_logic metavalues57
Duplicate, conflicting design unit names64
Missing return statement in function body66
Find unused ports67
Find unused generics68
Find dead states in state machines71
Warning with lightbulb Find incomplete sensitivity lists72
Find superfluous signals in sensitivity lists73
Find dead code (unreachable statements)79
Report encrypted files84
Find duplicate signals in sensitivity lists85
Detect signals and variables that are never written88
Detect signals and variables that are never read89
None or multiple matching entities for component90
Check naming conventions92
Warning with lightbulb Incomplete port map or generic map94
Vector width in assignments and port maps144
Warning with lightbulb All references must have the same capitalization as their declaration163
Warning with lightbulb Check for positional associations in instantiations164
Invalid port associations (incompatible port modes in instantiations)169
Warning with lightbulb VHDL version mismatch170
Warning with lightbulb Order of generic and port associations177
Incorrect component name in configuration180
Incorrect instantiation statement label in configuration181
Missing or incorrect binding indication182
Incorrect name in binding indication183
Incorrect use of keyword all184
Redundant boolean equality check with true185
Boolean equality check with false186
Warning with lightbulb Check for component/entity mismatch187
Header comment check188
Filename must contain primary unit name189
Empty loop statement190
Entity name is a Verilog or SystemVerilog keyword192
Instantiation mismatch198
Circular compilation dependency203
Type declaration not allowed in expression209
Index out of range210
Slice has wrong direction211
Unterminated string literal215
Extended identifier with whitespace may cause problems228

Deprecated code rules

Deprecated code rules were used by Sigasi Studio at some point, but they’ve been removed or superseded in the most recent version.

DescriptionReasonID
Invalid generic listSuperseded by 20224
Invalid generic mapSuperseded by 20225
Duplicate architecture for entitySuperseded by 6431
Port map lists cannot be terminated with a ,Superseded by 20245
Port lists cannot be terminated with a ,Superseded by 20246
Signal declarations are not allowed in a process statementSuperseded by 17656
End clause validationSuperseded by 5159
Duplicate entity for librarySuperseded by 6460
Duplicate package for librarySuperseded by 6461
Duplicate configuration for librarySuperseded by 6462
Invalid use clauseRemoved as it was invalid63
Duplicate design unit in IEEERemoved as it was invalid65
Find unregistered output portsRemoved as it was invalid75
Undefined identifierSuperseded by the linker87

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Tool Integration

Sigasi Studio supports a number of ways to work with external tools such as simulators. Different techniques offer varying degrees of flexibility and automation.

Most people will want to set up their external compilers so that Sigasi Studio can use them to compile and start simulations.

Another way to compile your project is to export your project to a CSV (comma separated values) list of all the files in your project, in the correct compilation order. Learn more about how to export your project’s file list.

The third, and more advanced way of working with compilers or simulators is to use the standard Eclipse mechanisms of builders and external tools.

By creating a builder, you can arrange for an external tool to be run automatically when a Sigasi Studio project is rebuilt. By default, this happens each time you save a file. External Tools Configuration allow you to call any program or script from within the Sigasi Studio GUI. You have to write and maintain the scripts yourself, but you have complete flexibility as to what is in the scripts.

External Compilers

If you have a simulator or lint tool installed, you can use this for two purposes:

  1. Save-time Compilation: Compile and check your files each time you save. Any errors or warnings will show up in the file, on the line number of the problrem
  2. Launch Simulator: Start the simulator in its own window, ready to run a simulation.

Learn about which external compilers are supported and how to Configure external compiler.

Launch simulator

If an external compiler is enabled, you can also start a simulation from Sigasi Studio. You can start a simulation by first selecting your top level in the Hierarchy View. Next click the Simulate button in the hierarchy view to launch the simulator gui with an elaborated design ready for simulation. Sigasi Studio opens a new console for each simulation launch. You can terminate a simulation by clicking the Stop icon .

When you launch a simulation, Sigasi Studio opens a new console in the Console View You can switch between different consoles by clicking the icon console display-icon.

Configure external compiler

You can configure the external compiler settings by clicking Window > Preferences > Sigasi > Toolchains. There is a sub-page for each supported toolchain. Before you can enable a toolchain on the main page, you must specify its installation path. Clicking Restore Defaults on a Toolchain page will automatically fill in the installation path if your toolchain is installed on a default location. After you press Apply, you can select your toolchain on the Sigasi > Toolchains page.

For some toolchains you can specify extra command line arguments. Note that these preference pages support Eclipse Variables which allow you to more easily share settings in a team.

Environment variables are supported too. If you want to use the $HOME environment variable, you can call this variable by typing ${env_var:HOME}.

List of toolchains

By “toolchains”, we mean any tool or set of tools that processes VHDL or Verilog code, and that is supported by Sigasi Studio. At this time, external compiler include simulators and lint tools, but in the future it could also include synthesis tools.

For each toolchain Sigasi Studio can support any combination of the following:

Currently the following external compilers are supported:

Toolchainsave-time compilationstart simulation
Aldec Riviera-PROtruetrue
Aldec Active-HDLtruefalse
Aldec ALINT-PROtruefalse
Intel Quartusfalsefalse
ModelSim / QuestaSimtruetrue
AMD/Xilinx ISEtruetrue
AMD/Xilinx Vivadotruetrue
Cadence Incisivetruefalse
GHDLtruetrue

Note: OneSpin was supported in Sigasi Studio from version 3.1 to 4.17 and provided save-time compilation and running of elaboration checks.

Notes

  • For information on where to obtain free HDL simulators, see this section in our FAQ.
  • GHDL does not support project dependencies.

Save-time compilation

Sigasi Studio can use an external VHDL or Verilog compiler for additional code validation. At this time, Sigasi Studio supports:

  • vcom / vlog / vsim style compilers. These compilers include Aldec Riviera-PRO and from Mentor Graphics ModelSim and QuestaSim.
  • isim compiler from AMD/Xilinx.
  • ncsim compiler from Cadence Incisive.

Catching bugs earlier is cheaper than catching them late. Traditionally, the first errors are found when the hardware designer decides to run a simulation. At this time, the simulator’s compiler tool will detect errors and fail. At Sigasi we think that this is too late. Problems should be detected as soon as possible.

Sigasi Studio adds two extra layers of error detection to catch problems earlier. First, there is the type-time error detector. As soon as the designer writes an error, it is marked in the text much like a spell checker in a word processor. Second, as soon as you save a file, Sigasi Studio calls the external compiler for further analysis. All errors that the external compiler finds are marked inside your file, so that you can find and fix them easily. Sigasi Studio intelligently controls the external compiler incrementally and only recompiles design files that need recompilation.

All output from external compilers is logged in Sigasi Studio’s console view for your convenience. Paths to your design files are automatically converted to hyperlinks to ease naviation.

The table below lists some examples of VHDL errors that are detected in Sigasi Studio at type time, at save time and with the external compiler integration.

CheckType timeSave timeSave time compile
Syntax errorsyesyesyes
Undeclared signalsyesyesyes
Multiple filesnoyesyes
Data type mismatchnonoyes
Multiple driversnonoyes

Libraries

Libraries are fully supported. But note that Sigasi Studio does not send Common Libraries to the external compiler for compilation. These libraries are expected to be pre-compiled. Contact support@sigasi.com if you want to add more libraries to this list.

If your project root contains a modelsim.ini file, Sigasi Studio will add this file to the vcom command with -modelsimini. This allows you to configure custom settings for Mentor’s vcom.

External Tools Configuration

Select Run > External tools > External Tools Configurations to get started, or use the icon.

To create a new configuration, first select Program, then click .

Enter all necessary information to start your external tool:

  • Name: The name for this configuration.
  • Location: The location of the executable. You can browse for programs and scripts in your workspace or programs on your file system.
  • Working Directory: The working directory for your program.
  • Arguments: The arguments, if any, to your program.

You can test your tool configuration with the Run button.

The following example screenshot shows how to set up configuration to run a simulate.sh script from within Sigasi Studio.

The following example screenshot shows how to set up a configuration to run make clean on a Linux machine.

To run the external tool just select the configuration from the dropdown menu on the -icon. You can rerun the last configuration by simply clicking .

Variables in Arguments

In the arguments field you can use variables, which are automatically expanded when the external tool is run. This allows you to do things like adding the currently selected file in the file explorer as an argument for an external tool configuration (${resource_path}).

Sigasi Studio adds following variables and parameters for VHDL and (System)Verilog projects:

Variable NameDescription
${library:<argument>}Get the library name of <argument>. For example, to the get the library of the currently selected resource use ${library:${resource_path}}
${sigasi_toplevel}Get the name of the current top level: library.name
${sigasi_toplevel:short}Get the name of the current top level without library: name
${sigasi_toplevel:project_path}Get the path of the current top level’s project root

Creating a Builder

An external tool configuration as described in the previous section makes it easy to run an external tool, but you still have to do so explicitly. For some programs, such as the make utility, it makes sense instead to do this automatically upon a change in your project. This functionality can be accomplished by a builder. We will show how to create a builder for a Modelsim Makefile as an example.

To create a builder, right-click your project and select Properties > Builders.

Click New… and the builder configuration window will pop up:

You will be asked to select a configuration type: select Program.

Next, configure the builder in a configuration window pop up window:

  • Name: The name of your builder, e.g. ModelSim.
  • Location: The location of the program, e.g. /usr/bin/make.
  • Working Directory: The working directory for your program. For example, click Browse Workspace… and select the root folder of your project.
  • Arguments: The arguments to your program, e.g. --makefile=Makefile.vsim all.

With the default settings the ModelSim Makefile will only be run during a manual build or after a “Clean”. To make sure Sigasi Studio runs make every time you save a change to a file, click the Build Options tab and check the During auto builds checkbox.

After configuration, the new builder will appear in the builder list.

When you close the builder configuration dialog windows, the new builder will automatically be run. In our example of a Modelsim Makefile, Modelsim’s messages will appear in the console view.

For the specific case of Modelsim, warnings and error messages in the console are made clickable. When you click a message, the corresponding location will automatically be opened in the Editor view.

You can add as many extra builders as you want. This can be useful for additional linting tools or code generators.

Intel Quartus integration

If you are using Intel Quartus 12.1 or higher, you can use Sigasi Studio as preferred HDL editor.

If you use the Sigasi Studio/ Intel Quartus integration, you can easily open VHDL files by double clicking on them in Quartus. Sigasi Studio will be aware of the entire Quartus project, so that you can perform project-wide searches and navigation actions in Sigasi Studio. Furthermore, if you add or remove files in the Quartus project, these changes are automatically applied in Sigasi Studio.

Note: If you want to set up a project independent of Intel Quartus, please read the documentation on setting up a project.

Setting the preferred editor

While importing a Quartus Project in Sigasi Studio, you have the possibility to configure Sigasi Studio as preferred editor in Intel Quartus. This offers the ability to open files in Sigasi Studio from within Quartus.

Open a Quartus Project in Sigasi Studio

After you have configured Sigasi Studio to be the preferred editor in Quartus, you can open files by double clicking on them in Quartus.

Sigasi Studio will import entire Quartus project and your file will open in the Sigasi Studio editor view. If you make changes to your Quartus project (like adding or removing files), these changes are reflected in Sigasi Studio as well.

The first time you import your project, it may take a few minutes. After that, you can leave Sigasi Studio open and double-click other files in Quartus to open them in the Sigasi Studio editor view.

If your Quartus Project File (.QPF file) contains a reference to a file that does not exist, Sigasi Studio will show an icon for that file with the broken link icon .

Quartus Preferences

The first time you import a Quartus project, Sigasi Studio will ask for the Quartus installation location. Sigasi Studio needs this path to find the Quartus libraries. You can change the Quartus installation location by selecting Window > Preferences > Sigasi > Toolchains.

Add files to your Quartus project in Sigasi Studio

To add a file to your Quartus project, you can use the default New VHDL file wizard of Sigasi Studio (File > New > VHDL File).

Add a new VHDL file to a Intel Quartus project in Sigasi Studio

Note that Quartus does not automatically update its UI after you add files to your project. In order to update the files list, you should run a work flow action in Quartus, like starting a compilation.

AMD/Xilinx integration

Setting the preferred editor

To open the Sigasi Studio editor from AMD/Xilinx, you first have to configure Sigasi Studio as preferred editor in Vivado or ISE.

Importing AMD/Xilinx Projects in Sigasi Studio

Vivado

The process of importing a AMD/Xilinx Vivado project is explained in Generating a Sigasi project from a Vivado project.

ISE

The process of importing a AMD/Xilinx ISE project is explained in Importing a AMD/Xilinx ISE project in Sigasi.

AMD/Xilinx Preferences

Vivado

You can change the AMD/Xilinx Vivado installation location by selecting Window > Preferences > Sigasi > Toolchains > Xilinx Vivado. Sigasi Studio needs this path to find the AMD/Xilinx Vivado libraries.

ISE

You can change the AMD/Xilinx ISE installation location by selecting Window > Preferences > Sigasi > Toolchains > Xilinx ISE. Sigasi Studio needs this path to find the AMD/Xilinx ISE libraries and to run the ISim compiler and simulator.

Export

You can export a list of all HDL files in your project, sorted in the correct compilation order. You can use your own simple scripts to manipulate such list and run any EDA tool, including simulators, synthesis and linter tools.

To export a comma separated value (CSV) list of files in your project, right-click your project and select Export…. In the Sigasi category, select CSV File. Then select the project you want to export. As a result, you get a file named compilation_order.csv, which lists the HDL files in your project in a valid compile order.

Example (for the tutorial project):

work, dut.vhd
work, clock_generator.vhd
work, testbench.vhd

This file will use relative paths, except when the file is on a different drive (on Windows).

Auto-export

You can also configure Sigasi Studio to auto-export this CSV file, every time the dependencies change.

Right click on the project you want to auto-export in the Project Explorer, and select Properties and Sigasi Auto Export.

Auto export CSV file with dependencies

If you do not set a fixed top level name (i.e. empty top level name in the property page), Sigasi Studio will use the current top level in the Hierarchy View as input. Note that this only works if the top level belongs to the selected project.

This information is stored in .settings/com.sigasi.hdt.shared.ui.prefs in your project.


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Sigasi Studio VUnit Integration

[Only in Sigasi Studio XPRT]

VUnit is an open source unit testing framework for VHDL and SystemVerilog. VUnit helps you to write tests more easily and run them frequently.

Sigasi Studio can help you manage VUnit projects and enables you to run and inspect test results straight from the IDE.

When you import a VUnit project or add VUnit support to an existing project, Sigasi Studio runs VUnit in the background and automatically adds the correct libraries - as specified by the VUnit script - to your project. It also shows error markers in the VUnit script (run.py) if anything goes wrong.

Since Sigasi Studio 4.14, the library mapping of the project is automatically updated based on the contents of the VUnit run.py script.

VUnit project

VUnit project setup in Sigasi Studio

Prerequisites

VUnit version 4.5.0 or higher is required.

Sigasi Studio needs to know where VUnit is installed. If you installed VUnit using pip install vunit_hdl and Python is in your path, then Sigasi Studio should find your VUnit installation. To verify whether Sigasi Studio can find your VUnit installation, go to Window > Preferences > Sigasi > Toolchains > VUnit and check the read-only VUnit installation path field.

If your Python installation is not in the path, you can configure it here in the Python executable location field.

If you have installed VUnit in a dedicated location, you should add the VUnit location to the $PYTHONPATH and make sure the $PYTHONPATH variable is visible to Sigasi Studio.

When you’re installing VUnit in a virtualenv, make sure to launch Sigasi Studio from within the terminal after activating the virtualenv.

If you installed VUnit from the Microsoft Store, you might get an error message when trying to select the Python executable. To use Python outside of Windows Store apps, Python needs to be installed using an installer from https://www.python.org/downloads/windows/.

You should make sure that the python run.py --version command only returns the VUnit version number. Additional output will prevent Sigasi Studio to parse the VUnit version number correctly and will result in errors.

Import VUnit Project

To import an existing VUnit project, click File > Import… > Sigasi > Import a VUnit project. Next, select the VUnit script (run.py) and the location for the Sigasi Project.

The VUnit project repository comes with a number of example projects which can be imported this way. If you first specify the Python Script Location, the Project Location will be set automatically.

Add VUnit support to an existing Sigasi project

You can also add VUnit support to an existing project: Right-click your project and select Configure > Add VUnit support. Next, select an existing run.py script or let Sigasi create an example script.

VUnit project

VUnit project configuration and troubleshooting

The VUnit integration in Sigasi Studio gives useful feedback in the VUnit Console View. To open this view, first open a console (Window > Show View > Other… > General > Console) and in the Console View toolbar click the triangle () next to the Open Console icon. Select VUnit Console to open the VUnit Console View.

Since Sigasi Studio 4.14, the library configuration from run.py is used to configure the library configuration in the Sigasi Studio project.

Note that this automatic configuration does not work with linked folders. You need to manually assign linked folders or any files/folders in them to a library.

Path separators in the run.py file need a /, also on Windows.

SystemVerilog

For SystemVerilog projects you need to manually add the VUnit include files to your projects:

  • Right click your project, select New > Folder > Advanced > Link to alternate location and add VUNIT/verilog/include as location.
  • Use the quick-fix on the failing `include "vunit_defines.svh" to add the include folder to the include paths.
Add verilog include path

Configure options for finding and running tests

In Window > Preferences > Sigasi > Toolchains > VUnit you can add different options for finding and running tests.

  • The Options for finding tests will be passed to run.py when generating the json file that lists the VUnit tests.
  • The Options for running tests will be passed to run.py when running the VUnit tests.
  • Select the Set VUnit output to project root to have the VUnit output stored in the project root instead of in the temp location from where VUnit is called.
VUnit preferences dialog

Run VUnit Tests

There are multiple ways to run VUnit tests in Sigasi Studio:

  • Right click your project and select Run VUnit tests to run all tests in your project.
  • Right click one or more HDL files and select Run VUnit tests to run all tests in the selected files.
  • Right click in the Sigasi editor and select Run VUnit tests to run all tests in the active editor.
  • Right click in the VUnit test name (the string in the run function call) and select Run VUnit test to run this single test only.
  • Rerun the tests in the VUnit view.
Run VUnit VHDL tests

Inspect VUnit Test Results

When you run VUnit tests in Sigasi Studio, the VUnit view is opened. This view presents a convenient way to inspect the test results.

VUnit SystemVerilog Example

You can also open the Console View to inspect the entire VUnit output.

VUnit console view

Handling specific common libraries

In Sigasi Studio, Common Libraries may be present in a project. Some of these are standardized and available in all tools, e.g. IEEE VHDL libraries, or the VUnit library in case of a VUnit project. Your project may also require vendor or company specific common libraries. External simulators, including the simulator which runs your VUnit tests, require a particular setup to find your library.

If, for instance, ModelSim is used, then:

  • common libraries need to be pre-compiled,
  • a customized modelsim.ini with a reference to the pre-compiled libraries is required, and
  • VUnit needs to be aware of the customized modelsim.ini.

The latter is achieved by setting an environment variable VUNIT_MODELSIM_INI which points at the customized modelsim.ini. One could set this variable from the shell (Linux) or user variables (Windows), but that is inconvenient as all projects will use the same modelsim.ini. A better solution is to set VUNIT_MODELSIM_INI in the run.py script, before calling VUnit.from_argv().

# This is run.py
# code omitted
os.environ['VUNIT_MODELSIM_INI'] = '/path/to/custom/modelsim.ini'
vu = VUnit.from_argv()
# code omitted

Note that VUnit may still produce warnings that the library is missing, as shown below. These warnings are harmless. They show up because only Sigasi Studio and the simulator are aware of the library, while VUnit is not.

WARNING - C:\Users\Wim Meeus\workspaceSigasi\VUnit-demo\design\design_top.vhd: failed to find library 'vucommon'

Alternatively, one could define the library and its contents in the run.py script. In that case, VUnit will be aware of the library and the warnings won’t show, but compile times will be longer - which is exactly what common libraries are meant to avoid.

Using an external compiler in a VUnit project

If you want to configure an external compiler in a VUnit project (e.g. for additional syntax checking), you need to ensure that the compiler has the VUnit library. Otherwise, the compiler will flag all VUnit constructs in your HDL code as errors.

How to compile and enable the VUnit library for an external compiler is explained in the libraries section of this manual.


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Documentation Generation

The Sigasi Studio documentation generator makes the documentation process easier by automatically extracting information from your HDL source files. The biggest advantage is that there is only a single source for both your design and your documentation. While this gives no guarantee for the design staying in sync with the documentation, it certainly makes it easier.

The Sigasi documentation generator has following advantages:

  • No special coding requirements: the plain comments in your code are extracted for the documentation, no need for special annotations. Sigasi uses the same comment association as the hover provider. So to document a port, you append a comment to a port declaration. To document an architecture, you put the comment just on top of the architecture.
  • All included. All documentation processing is done in Sigasi/Eclipse. So you do not need to install extra tools.
  • Fully hyperlinked. If you export the documentation, you get a fully hyperlinked document.
  • Live preview: you can see what the documentation will look like while you type your code and comments.

Export Documentation

You can export documentation for the entire project or a specific toplevel by clicking the save icon on top of the Documentation View or via the Export… menu.

  • When you select the entire project, the design elements will be listed in alphabetical order.
  • When you select a specific toplevel, design elements will be ordered in a breadth-first order from the top down.

The resulting HTML file is saved in the sigasi-doc folder in the root of your project. The generated Block and State Machine Diagrams are saved in subfolders of the sigasi-doc folder.

Sigasi Studio 4.5 introduced exporting the documentation to HTML. You have to choose between Linked resources and Embedded resources when exporting the documentation.

  • Linked resources
    Creates an HTML document with linked resources. All Block Diagrams and State Machine Diagrams are in separate files which are linked from within the HTML document. The custom CSS file, if present in the project root, will be referenced from the HTML document.

  • Embedded resources
    Creates an HTML document with embedded resources. The documentation is in a single file. The Block Diagrams and State Machine Diagrams are embedded in the HTML document. The CSS from the custom CSS file, if present in the project root, will be included in the HTML <head>.

Any errors are logged to the console view.

Customization

Sigasi Studio 4.17 introduced pagination and the introduction and problems section.

Pagination and problems configuration

Pagination

Enabling the Split pages by elements count will paginate the output documentation. This is useful for very big designs that produce documentation 100’s of MBs large.

The summary information about the design appears on the first page and fans out to subsequent pages that will contain the documentation about individual design elements.

Paginated documentation

Problems section

Enabling Include problem information will add a Problems section containing all the project’s Errors, Errors and warnings, or Errors, warnings, and infos. On top of that, the suppressed problems can also be shown.

Problems reported in the HTML documentation

Introduction section

If a sigasi-doc.md file is present in the root directory of your project, Sigasi will automatically include it in the exported documentation as an introductory chapter.
As usual with our documentation, this is a MarkDown file. This allows you to easily annotate the text.

Further customization

The exported HTML documentation can be further processed, as explained in Use a Word macro to Scale Diagrams in HTML documentation.

Graphics

The exported documentation includes the Dependency Diagram, State Machine and Block Diagrams. If you created custom graphics configurations for one or more of your diagrams, these will be used instead of the default diagrams.

If you have multiple graphics configurations for the same diagrams, the alphabetically first one is used.

Custom CSS

If the root of your project contains a sigasi-doc.css file, this file will be used to style the generated HTML documentation. Note that only the generated HTML will be affected and not the Documentation View.

For example, you can give the background and titles different colors. You can also change the font for the entire document or parts of it.

body {
   background-color: Azure;
   font-family: sans-serif;
}

h1 { color: Tomato; }
h2 { color: Orange; }
h3 { color: Gold; }
h4 { color: Aquamarine; }
h5 { color: BlueViolet; }

Entire sections for entities, architectures and modules can be given different background colors. Likewise the list of processes can get a different background color.

.entity, .module { background-color: AliceBlue; }
.architecture    { background-color: Cornsilk; }
.processes       { background-color: WhiteSmoke; }

Tables can be made striped. Within sections, you can specify different colors for the striped table.

tr:nth-child(even) { background-color: Lavender; }
.entity table tr:nth-child(even) { background-color: FloralWhite; }

It’s also possible to hide parts from view.

#revision { display: none; }

The difference in documentation with the CSS settings described above is shown in the screenshots below.

Comparing generated documentation with and without custom CSS

Comment Association

Comments in HDL code are used to add extra information or documentation to that code. Sigasi Studio uses certain rules to determine which comment belongs to which code. This is important for documentation hovers, refactoring, formatting,… Which comment belongs to which exact code is subjective.

Sigasi Studio associates comments with HDL declarations with following rules:

  • If there is a declaration before a comment in the same line (trailing comment), the comment is associated with this declaration. This comment can span multiple single line comments if they are aligned.
  • If there is no trailing comment and there is a comment with the same indentation on the line above the declaration, the comment is associated with this declaration. This comment can span multiple lines if all comments have the same indentation.
  • Empty lines break comment blocks

The association rules are illustrated in the image below:

comment association rules

The Formatter and Structural select respect (and fix) comments according to the association rules.

Special cases

  • VHDL components and component instantiations: If a component (or one of its ports or generics) does not have comment itself, Sigasi Studio will use the comment of the corresponding entity. This also works for component instantiations.

Comment markup with Markdown

VHDL and SystemVerilog comments are processed with a Markdown processor. This allows to add markup (e.g. bold, code, paragraphs, hyperlinks,…) to comments. This results in nicer hovers and documentation.

Markdown in comments

In hovers the complete Markdown syntax is supported. For documentation generation following features are supported:

  • paragraphs (add and empty comment line to break paragraphs)
  • line breaks (by adding two trailing spaces)
  • emphasis (*emphasis*)
  • strong (**strong**)
  • lists
  • tables (with alignment)
  • external links and email addresses (<https://www.sigasi.com>, [Sigasi](https://www.sigasi.com) and <sales@sigasi.com>)

Sigasi Studio 4.6 added support for Fenced Code blocks in comments. This enables you to add text to the documentation without Markdown rendering. To add a comment verbatim to the documentation, surround it with with triple back ticks: ```<verbatim comment>```


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Graphics Configuration

This feature has been deprecated since Sigasi Studio 4.16. A new and improved solution will be introduced soon.
[Only in Sigasi Studio XPRT]

The BlockDiagram- and StateMachine views are a very useful way to explore and understand HDL designs, but sometimes that just doesn’t cut it. The diagrams can be too complex and crowded to understand a design. For this reason, the diagrams can’t always be directly used in documentation. To solve this challenge you can make use of the Graphics Configuration Language.

The Language

The Graphics Configuration Language is a plain text file containing declarations and configurations, which when interpreted, result in grouping, filtering and coloring in the diagram. You can see it in action in the images below:

This BlockDiagram

Original BlockDiagram

Turns into:
Filtered BlockDiagram

This StateMachine

Original StateMachine

Turns into:
Filtered StateMachine

A plain text format was chosen over a buttons and menus for several reasons:

  • It can easily be managed with your version control system because files can easily be compared and merged.
  • It’s easy to debug by yourself, unlike proprietary formats or UIs.
  • We can support you using all of our well-known features such as auto-complete, validations, formatting,…
  • It’s lightweight and can be used as the basis for the UI implementation.

Getting started

To get started, choose a design with a BlockDiagram or StateMachine you want to simplify.

Create a new Graphics Configuration file by going to File > New > Other > Graphics Configuration > Graphics Configuration File. You can also press the Sigasi button on the top right of the BlockDiagram or StateMachine view.

From there, you can declare groups and configure your diagram, check it in to version control and share it with your colleagues. Auto-complete (Ctrl+Space) helps you write most of the code while formatting (Shift+Ctrl+F) helps you to keep your file clean. If you’re interested in the language’s exact syntax, you can find it here.

Features

The Graphics Configuration features:

  • Grouping
  • Hiding
  • Reassignment hiding
  • Block collapsing
  • Coloring
  • Regex matching

Note that in the BlockDiagram you can group blocks and wires while in the StateMachine you can only group states.

Graphics Configuration Editor features:

  • Auto-complete (Ctrl+Space)
  • Formatting (Shift+Ctrl+F)
  • Quick outline (Ctrl+O)
  • Show in BlockDiagram/StateMachine (Alt+Shift+W)
  • Navigate to declaration (Ctrl+click or F3 on identifier)
  • Double-click on a diagram element to navigate to it in the code
  • Hovering to show more information

Graphics Configuration for BlockDiagrams

You can express which diagram you want to filter in the first line of the file by writing diagram fullyQualifiedName. The fully qualified name in VHDL is always library.entity.architecture. In SystemVerilog this is work.module.
E.g. if you want to filter the diagram for the architecture RTL implementing the entity ent in the work library, you use the following line as the first line: diagram work.VME64xCore_Top.RTL.

The file is read from bottom to top. You start with the above definition of the diagram, then within that you can hide reassignments, create groups and finally, create configurations for ports, blocks and edges.

Hiding reassignments

When using a lot of reassignments or when you’re indexing vectors, you can get a skyscraper effect in the generated block diagrams. By using reassignments hide you can draw through the assignment blocks making the diagram a lot simpler.

Skyscraper

Skyscraper

Hidden reassignments

Hidden reassignments

Multiple reassignments

Multiple reassignments

Hidden reassignments

Hidden reassignments

Grouping

After hiding the reassignments you can define groups of edges or blocks. The syntax for a group is as follows:
def Type group ID (Identifiers)
Where Type is block or wire, ID is the new name of the group and Identifiers is a comma separated list of existing IDs (Graphics Configuration, VHDL or SystemVerilog) or a regex.

The syntax for a regex is regex"regex_pattern". This uses Java regexes, you can also find a cheat sheet here. You can also check what the regex matches by hovering over the query.

E.g. if you want to group block2 and block3 you can add either of the following lines:
group block middle regex"block[23]"
group block middle (block2, block3)

Ungrouped

Ungrouped

Grouped

Grouped

The same can be done for wires by using wire instead of block.
Ports can be grouped by grouping the wires attached to the ports into a bus.

Configuration

The syntax for a configuration block is as follows:
Type Identifiers { ConfigurationItem* }
Where Type is block, wire or port.

The syntax for a ConfigurationItem is as follows:
hide | collapse | color GraphicsColor | reassignments hide
You can discover which colors are available here or through the autocomplete.

E.g. we can color a block, called middle, green and hide its internals:
Colored and collapsed group

Colored and collapsed group

Configurations are not cascading (unlike CSS). Coloring the middle block green does not turn all its internal blocks green as well.

Note that the language can not see everything: it can not see blocks, wires or ports that are within another block.
E.g. we can’t type block block3 { color red } as block3 is part of the block middle. To access a block within a block, we have to nest configurations.

Nested configuration

Nested configuration

Another use case would be to hide (unconnected) ports by using port a { hide }.

Hidden port

Hidden port

Note that when you hide a block or port, the edges that are connected to them will also be hidden.

It is also possible to hide reassignments in configurations, as you saw in the above skyscraper example, the reassignment in the generate block was not hidden. You can do so as follows:

Hidden reassignment in generate

Hidden reassignment in generate

Graphics Configuration for StateMachines

StateMachines are configured in the same way as the above BlockDiagrams, except the only Type that can be used is state. The header is also slightly different, the syntax is as follows:
statemachine architecture : state_variable.

For an example you can check out step_3_state_machines.vhd (in our VHDL Tutorial) with this filter file.

Example of a state machine diagram configuration

Hiding labels

Labels on state transitions can be hidden using labels hide.
You can also use labels comment or labels condition to only show comment or condition labels on the state transitions.


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Third Party Plugins

Since Sigasi Studio is built on Eclipse, you can install third-party Eclipse plugins.

The best place to start looking for a plugin is the Eclipse Marketplace. We list some interesting plugins here. Since these are third-party plugins, there is no official support from Sigasi.

Installing Plugins

Unlike most Eclipse distributions Sigasi Studio is shipped without the Eclipse Marketplace plugin and the standard Eclipse update sites. Hence, you have to add a plugin update site to install new plugins.

  • Adding the update site
  • Installing
    • Still in the Install dialog, search for the plugin you want to install. You can browse the list of available plugins or use the filter text above the list of plugins.
    • Select the checkbox for the plugin and click Next
    • Follow the instructions for the rest of the wizard.

Revision Control Systems

Sigasi Studio supports a wide range of Revision Control Systems (also known as Version Control or Source Control systems). Support for revision control is based on Eclipse plugins. This section contains a preliminary listing of the most popular revision control systems.

GIT

Recommended plugin: EGit This plugin is shipped with the standalone version of Sigasi Studio.

Subversion (SVN)

For Subversion we recommend the Subclipse plugin.

To install this plugin, perform these steps in the Help > Install New Software… window:

To install older versions of Subclipse or if you need more information on Subclipse, you can refer to the documentation on https://github.com/subclipse/subclipse/wiki.

Note that we no longer recommend the Subversive plugin since it is only available up to Eclipse oxygen.

ClearCase

Recommended plugin: ClearCase (Update site: http://eclipse-ccase.sourceforge.net/update/)

Note that this is the Open Source ClearCase plugin hosted on SourceForge, not the official ClearCase plugin distributed by IBM.

Local History

While this is not strictly speaking a version control system, Sigasi Studio has a built-in feature that keeps a local history of your files. Learn more.

Other Systems

Some other popular revision control systems include:

  1. CVS learn more.
  2. Mercurial (Hg) learn more.
  3. Perforce learn more.

VI and Emacs

Other Languages

Remote Collaboration

  • You can use the Saros plugin to remotely collaborate on the same project with multiple people. You’ll see edits from collaborators in your own editor as they happen. To install the Saros plugin in Sigasi Studio, use https://www.saros-project.org/update-site/eclipse as update site.

Opening to a Shell


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Troubleshooting

The user interface is unresponsive

If the user interface of Sigasi Studio is unresponsive, you can interrupt the internal compilation process by pressing the stop button in the progress view. To activate the progress view, select Window > Show View > Other… > General > Progress, or click the tiny conveyor belt icon Conveyor belt icon, on the right side of the status bar.

Create performance and memory snapshots

Performace snapshot

Sigasi Studio has a built-in profiler. By default this profiler is not active. On some occasions we’ll ask you to provide an anonymized performance snapshot from the profiler. To obtain this snapshot, follow the steps below.

  • Activate the profile using Help > Sigasi > Performance > Start Async Sampling
    On Windows, use Help > Sigasi > Performance > Start Sampling instead.
  • Perform the laggy operations in Sigasi Studio
  • Stop the profiler using Help > Sigasi > Performance > Stop Profiling

Memory snapshot

It may happen that, as part of a support case, we’ll ask you to provide an anonymized memory snapshot of a running Sigasi application. To obtain this snapshot, select Help > Sigasi > Performance > Capture Heap . You’ll be prompted for a location and a filename to store the memory snapshot.

Sending your snapshot to Sigasi

The snapshot you’ve obtained needs to be obfuscated to anonymize it and it needs to be uploaded.

Sigasi support will provide instructions.

The editor displays old contents of a file

If you edit a file outside of Sigasi Studio with an external editor, Sigasi Studio will normally notice the changes and ask if you want to load the changes. If it doesn’t, you can refresh the editor’s content by pressing F5 or by right-clicking a file or a project in the project explorer and selecting Refresh.

No content in the editor and only a cross in the editor tab

If you see empty views in Sigasi Studio on Linux: make sure libXss or libXscrnSaver is installed.

How much local history will be stored?

Sigasi Studio stores the history of your file so that you can compare your current version with the version you saved an hour ago.

You can define how much disk space is used for storing local history in Windows > Preferences, select General > Workspace > Local History.

For more information on local history, check out this page.

I see hundreds or thousands of errors

If you see a large number of errors, you either have very, very buggy code (not so likely) or your project is not configured correctly.

  1. Check that all files are mapped to the correct library.
  2. Check that all stale files are ignored. (see the section on unneeded files)
  3. Check that all third party libraries are included.
  4. Make sure that automatic build is enabled.

Auto Build is not Enabled

Symptoms:

  • When you introduce an error in a VHDL or Verilog file and save the file, an error marker shows up in the file, but not in the problems view.
  • Navigation (Find References, Open Declaration) behaves strangely when it involves more than one file.
  • Other features that involve multiple files behave incorrectly: autcomplete, refactoring, …

Cause: Project is not built automatically

Resolution: Enable automatic project builds: Project > Build Automatically

Project does not have VHDL support

Symptoms:

  • VHDL files contain errors, but these errors do not show up in the Problems View.
  • Cannot select a top level in the Hierarchy View
  • Cannot navigate from a name in one file to its declaration in another file.
  • In the Project Explorer, the name of the library (for example: [work]) is not shown next to the filename.

Cause: The project does not have VHDL support enabled

Resolution: Enable VHDL support: right-click the project > Configure > Add VHDL support

Project does not have Library Mapping Information

Symptoms:

  • All VHDL-files in the project are not mapped
  • The Project contains only one error: “This VHDL project can not be built since the library mapping information is missing”
  • VHDL files contain errors, but these errors do not show up in the Problems View.
  • In the Project Explorer, the name of the library (for example: [work]) is not shown next to the filename.

Cause: The project does not have a (valid) VHDL library mapping information file

Resolution: Reset the library mapping: right-click the project > Library Mapping > Reset Library Mapping

Project does not have Common Libraries

Symptoms:

  • Project has many errors, in practically all files. Project build may be slow.
  • The standard data types (like integer and std_logic) are not recognized.
  • The IEEE and STD libraries are not recognized.
  • The IEEE and STD files are either missing or are mapped to the wrong library (for example: [work]).

Cause: Common libraries are not configured correctly.

Resolution: Reset the common libraries: right-click the project > Library Mapping > Reset Library Mapping

Sigasi Studio analyzes HDL files that I do not need

By default, Sigasi Studio assumes that all VHDL or Verilog files are part of the project. However, some projects may contain multiple files with older or alternative definitions of a VHDL object. We call these stale files, because they are no longer used. In such a case you will want Sigasi Studio to ignore certain files.

To exclude files (or directories) from analysis, consult the Libraries manual page.

Ignored resources are decorated with a icon in the project explorer view.

Sigasi Studio startup fails: “Could not create the Java virtual machine”

On some computers, the standalone version of Sigasi Studio will fail to start with an error message similar to: “Could not create the Java virtual machine.” This happens especially on 32-bit Windows machines with less than 2GB of physical memory. The reason is that the Java virtual machine tries to allocate more memory than what is available.

In order to solve this, you can decrease the default heap size settings. You can do this by adding following lines to sigasi.ini or eclipse.ini in your Sigasi Studio installation folder:

-vmargs
-Xmx1000m

This sets the maximum heap size to 1000 MB (instead of the standard 3GB).

Note: Do not use eclipsec.exe, as this will ignore all of the settings configured in the eclipse.ini file.

Sigasi Studio shows a startup message about port 4444 already being in use

If you want to run Sigasi Studio on a server with multiple users, the configuration files should be updated according to the descriptions here.

I want a clean restart

If you ever suspect that the state of your project is inconsistent in Sigasi Studio, you can do one or all of the following things. Consider these steps to be advanced usage; you should not need them during normal operation.

Force a clean compilation

You can force a completely clean compilation by selecting: Project > Clean … > Clean All Projects > OK.

Remove stale markers

Sometimes markers remain visible, even after the problem is fixed or when a file is excluded from compilation. We call these stale markers and they are can be caused by a crash during compilation.

You can delete these stale markers from the Problems View: In the Problems View, select the markers and press DEL (or right-click and select Delete).

Note that during the next build, the tool may generate new markers. If you want to suppress certain warnings, you can configure the linting rules.

Remove the cache

For faster performance Sigasi Studio is using a cache. Sometimes the cache can get corrupted which might cause internal errors. The cache is located in your workspace. By default, Sigasi Studio’s workspace is located in ${HOME}/workspaceSigasi.

To remove the cache, stop Sigasi Studio and delete the folder workspaceSigasi/.metadata/.plugins/com.sigasi.hdt.shared.ui/resource.cache/sigasiBuildCache.

Remove the workspace state

Much of your configuration and cached data is stored in your workspace. By default, Sigasi Studio’s workspace is located in ${HOME}/workspaceSigasi. A lot of this data is stored in the hidden .metadata directory. Sometimes, a part of your metadata can become corrupt. It can help to remove the .metadata directory (take a backup first!). This clears all of your workspace state.

  • You will need to enter your license code again.
  • You will need to import your projects again. Import > General > Existing Projects into Workspace

Keep getting reports about an “Incompatible version of Quartus”

If you are using the integration with Intel Quartus. Some people keep getting a dialog box that says something like:

Incompatible version of Quartus

Project interface was created with an older, incompatible version of Quartus. Is it OK to upgrade the project to match the installed version of Quartus?

Obviously, you should upgrade the project. If this message keeps popping up, you may want to check that Sigasi Studio is using the correct version of Quartus, in the Sigasi Studio application: Window > Preferences > Sigasi > Toolchains > Intel Quartus.

Contact support

If this troubleshooting guide did not solve your problem, please send us an email .

Any of the following information will help us help you:

  • Steps to reproduce your problem
  • Description of the expected behavior and the actual behavior.
  • A VETSMOD code snippet.
  • A screenshot
  • The version number of your Sigasi Studio: Help > About Sigasi > Installation details Note that the version number contains the date of the release. (For example, version 2.0.1.20110809… was released on August 9, 2011.)
  • The log file: Help > Open Log

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Keyboard Shortcuts

As you become more experienced with Sigasi Studio, you will find that there are a number of actions that you perform quite often. At some point, you may feel that the GUI-based approach becomes too slow for these actions. For that reason, Sigasi Studio provides a number of keyboard shortcuts. They are a great way to boost your productivity. A printable cheat sheet with all shortcuts on one page is available for download.

A printable cheat sheet with all shortcuts

In this chapter, we describe the available keyboard shortcuts.

Top keyboard shortcuts

In this section, we list the most important shortcuts.

  1. Open Resource (Shift+Ctrl+R):
    Shift+Ctrl+R opens a dialog that allows you to swiftly open an editor on any file in the workspace.
  2. Open Declaration (F3):
    Use F3 to navigate to the declaration of the selected identifier.
  3. Open Design Unit (Shift+Ctrl+D):
    Shift+Ctrl+D opens a dialog in which you can type a name or pattern to open a specific VHDL or SystemVerilog design unit name.
  4. Backward History (Alt+Left):
    Often, when you navigate to a declaration you want to go back to where you came from; just press Alt+Left.
  5. Content Assist (Ctrl+Space):
    With content assist (autocomplete) you can really speed up coding VHDL. Just press Ctrl+Space to get a suggestion of possible autocompletes in the current context.
  6. Go to next marker (Ctrl+.)
    Does your file contain warnings or errors? Quickly navigate to the next problem by pressing Ctrl+. (Ctrl+, jumps to the previous problem).
  7. Quick Fix (Ctrl+1):
    To fix problems even quicker, navigate to the problem with the previous shortcut. Press Ctrl+1 to activate the Quick Fix, select the fix with the UP or DOWN keys and execute the Quick Fix with Enter.
  8. Go to Line (Ctrl+L)
    You can directly jump to a certain line with this shortcut. You can display the line numbers by right-clicking on on the gray bar on the left side of the editor view and clicking on Show Line Numbers.
  9. Search references (Shift+Ctrl+G)
    To search for all occurrences of a given identifier, just select the identifier and press Shift+Ctrl+G. The search view is displayed, with a match for each occurrence (possibly in multiple files)
  10. Rename Refactoring (Shift+Alt+R)
    Once you get used to the rename refactoring you will be using it all the time. Use Shift+Alt+R to run it even quicker.
  11. Toggle Block Selection (Shift+Alt+A)
    Switch between regular and block selection mode.
  12. Structured Select (Shift+Alt+Up/Down/Left/Right)
    Select VHDL or Verilog code, based on its syntactic structure. (Structured selection)
  13. Format (Shift+Ctrl+F)
    Format your current VHDL or SystemVerilog file.
  14. Quick Access (Ctrl+3, This is the shortcut to use, when you forgot the shortcut you actually need.)
    With Quick Access you can quickly find open editors, available perspectives, views, preferences, wizards, commands, etc. Simply start typing the name of the item you wish to invoke.

Keyboard shortcut reference

CategoryDescriptionKeyboard shortcut
Basic EditingDeleteDelete
CopyCtrl+C, Ctrl+Insert
PasteCtrl+V, Shift+Insert
CutCtrl+X, Shift+Delete
UndoCtrl+Z
RedoCtrl+Y
Select AllCtrl+A
Toggle Block SelectionShift+Alt+A
Toggle Word WrapShift+Alt+Y
Zoom inCtrl++
Zoom outCtrl+-
Quick FixesQuick FixCtrl+1
AutocompletionContent AssistCtrl+Space
Word completionAlt+/
Basic SearchFind and ReplaceCtrl+F
Find NextCtrl+K
Find PreviousShift+Ctrl+K
Incremental FindCtrl+J
Incremental Find ReverseShift+Ctrl+J
FilesPrintCtrl+P
NewCtrl+N
RenameF2
Close AllShift+Ctrl+F4, Shift+Ctrl+W
RefreshF5
CloseCtrl+F4, Ctrl+W
PropertiesAlt+Enter
SaveCtrl+S
New menuShift+Alt+N
Save AllShift+Ctrl+S
NavigationLast Edit LocationCtrl+Q
Open ResourceShift+Ctrl+R
Open Design UnitShift+Ctrl+D
Backward HistoryAlt+Left
Show In…Shift+Alt+W
Go to LineCtrl+L
Go to Matching BracketCtrl+Shift+P
PreviousCtrl,*
NextCtrl.*
Collapse AllShift+Ctrl+Numpad_Divide
Forward HistoryAlt+Right
VHDL/Verilog specificSearch referencesShift+Ctrl+G
Rename - RefactoringShift+Alt+R
FormatShift+Ctrl+F
Toggle CommentCtrl+/
CommentShift+Ctrl+/
UncommentShift+Ctrl+*
Open DeclarationF3
Open matching entityShift+F3
Go to next problemCtrl+.
Go to previous problemCtrl+,
Expand structured selectionShift+Alt+Up
Contact structured selectionShift+Alt+Down
Expand structured selection leftShift+Alt+Left
Expand structured selection rightShift+Alt+Right
Advanced searchFind Text in WorkspaceCtrl+Alt+G
Open Search DialogCtrl+H
Previous WordCtrl+Left
Advanced editingInsert Line Above Current LineShift+Ctrl+Enter
Scroll Line DownCtrl+Down
Delete Next WordCtrl+Delete
Test StartCtrl+Home
Toggle OverwriteInsert
Insert Line Below Current LineShift+Enter
Delete Previous WordCtrl+Backspace
Delete LineCtrl+D
Copy LinesCtrl+Alt+Down
Duplicate LinesCtrl+Alt+Up
Move Lines DownAlt+Down
Delete to End of LineShift+Ctrl+Delete
Select Next WordShift+Ctrl+Right
Scroll Line UpCtrl+Up
Select Line EndShift+End
Move Lines UpAlt+Up
Join LinesCtrl+Alt+J
To Upper CaseShift+Ctrl+X
Select Line StartShift+Home
To Lower CaseShift+Ctrl+Y
Select Previous WordShift+Ctrl+Left
Next WordCtrl+Right
Text EndCtrl+End
Line StartHome
Line EndEnd
Show Tool TipF2
ViewsMaximize Active View or EditorCtrl+M
Next EditorCtrl+F6
Next ViewCtrl+F7
Show View MenuCtrl+F10
Show Key AssistShift+Ctrl+L
Show System MenuAlt+-
Show Ruler Context MenuCtrl+F10
Previous EditorShift+Ctrl+F6
Activate EditorF12
Switch to EditorShift+Ctrl+E
Previous ViewShift+Ctrl+F7
Quick AccessCtrl+3
Quick Switch EditorCtrl+E
Toggle Full screenAlt+F11
Toggle Horizontal Split EditorCtrl+_
Toggle Vertical Split EditorCtrl+{

MacOS users

Please note that from version 5.0 onwards, Sigasi Studio is no longer supported on MacOS.

If you are using MacOS, most of these keyboard shortcuts use Command instead of Ctrl. To inspect the exact list of keyboard shortcuts, go to Preferences > General > Keys.

Customizing keyboard shortcuts

Keyboard shortcuts can be easily customized via Preferences > General > Keys.

This preference page also enables you to select the Emacs scheme, for more Emacs-like keyboard shortcuts, or (if you have installed the UltraEdit key bindings for Eclipse plugin) the UltraEdit key bindings.

If you’re looking for Vi or Emacs keybindings, have a look at Third Party Plugins.


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Advanced Sigasi Studio setup

The advanced setup of Sigasi Studio is meant for engineers and organizations who want to:

  • automate the setup of Sigasi Studio
  • automate the setup of a project (or a set of related projects)
  • combine Sigasi’s VHDL and SystemVerilog support with other programming languages, version control settings, or different Eclipse plugins
  • ensure that all team members share the same settings (indent style, templates, linting preferences…).

The advanced setup uses Oomph, a highly customizable installer for Eclipse. Oomph is configured with setup files. Most of the team members will use these files when setting up a new version of eclipse and/or when they join a new project. Only every now and then, e.g. at the start of a new project, a setup file needs to be created or updated.

For the standard setup procedure for Sigasi Studio, look here.

The user perspective: using existing setup files.

Setting up the latest version of Eclipse with the Sigasi Studio plugin is easy and straightforward. One or two files are needed:

  • The product setup file determines the Eclipse setup, e.g. plugins and workspace settings.
  • The optional project setup file tells Eclipse how to set up a project, e.g. from a version control system.

oomph flow

To get the installation started, download, unzip and run the Eclipse installer. In the top-right corner, click the 3 horizontal bars (the burger menu) and select Advanced Mode….

oomph advanced

Next, click on the plus icon next to the filter text and enter the URI of the product setup file. This can be a file on your system or a web link, e.g. to a file on your team’s internal web page. For demo purposes, you can use our example file: https://insights.sigasi.com/resources/manual/SigasiStudio.setup. Click OK to close the pop-up.

oomph setup file

Select the desired product setup under User Products and click Next >.

oomph select product

Now you can optionally select a project to set up. Again, click the plus icon next to the filter text and enter the URI of the project setup file. You may want to try our demo project from https://insights.sigasi.com/resources/manual/SigasiDemoProject.setup which will set up a Sigasi project using git version control. Select the desired project (checkbox) and click Next >.

oomph select product

Next, configure the path for your Eclipse installation, workspace and project. Check Show all variables to see all relevant paths. Make changes if required and click Next > to continue. In the next screen, click Finish to start the setup process.

oomph set paths

At the end of the product setup (Eclipse install), Eclipse starts up. If a project setup was selected, a second Eclipse installer starts for that purpose. When finished, the Eclipse installer window(s) may be closed by clicking Finish.

Your new Eclipse with Sigasi Studio is now ready, with the optional project if one was selected.

Setting up the setup files

So far, we’ve seen how a user can set up Eclipse, Sigasi Studio and projects quickly and easily using setup files. These setup files are convenient for teams to keep tool settings consistent between team members.

This section discusses how to create and modify setup files. Setup files use the XML format, which means that they are structured text files and therefore human readable. The Eclipse Oomph plugin has a convenient graphical editor for these files. Using a text editor is error-prone and therefore not recommended.

Setting up Eclipse Oomph

Oomph is an Eclipse plugin, so you’ll want to either run Oomph in your current Eclipse, or install a separate (minimal) Eclipse. The Eclipse installer can be found here. Recent versions of Eclipse contain Oomph by default, so you shouldn’t need to install anything extra.

If your Eclipse doesn’t contain Oomph, open Eclipse, go to Help > Install New Software…, enter http://download.eclipse.org/oomph/updates/release in the box next to Work with, select the Oomph Setup > Oomph Setup and proceed with the installation.

oomph setup

Then, create a new General project to contain the setup files: File > New > Project… > General > Project, name the project and click Finish.

Now you can either create new product and project setup files in this project, or copy (drag & drop or otherwise) files into the project for customization.

Product setup file

For a product setup file, it is recommended to start from one of our examples: either a fairly minimal SigasiStudio.setup or an example in which a few extra workspace options are configured: SigasiStudioPlus.setup. Place one of these files in your Oomph project and open it for further customization.

If you prefer to start from scratch, right-click your Oomph project and select New > Other… > Oomph > Setup Product Model, and check out one of the above examples for the basic configuration.

oomph product edit

Both examples will install Eclipse with Sigasi Studio and Git revision control. The minimal example will, in addition, configure the maximum heap space for Eclipse, it will enable the Sigasi perspective, and it will turn off the Preferences Recorder. The extended example, shown above in the Oomph editor, contains further options for linting severities, formatting options and an auto-complete template.

Note the three groups of settings:

  • Eclipse Ini: settings that will go in eclipse.ini.

  • P2 Director: plugins to install and the repositories where they can be found. Here you can add additional plugins, e.g. to support an additional programming language or a different revision control system. To add an item, right-click P2 Director, and select New Child > Requirement for an additional plugin, and subsequently New Child > Repository for the plugin repository.

  • Custom preferences: workspace settings. Here you can fine-tune workspace settings to the need of your team. To add a new preference, first find the key and the value of the preference which you want to configure (see below). Then, right-click Custom preferences and select New Child > Preference. Then fill out the key, the value and the optional description.

Finding keys and values of workspace preferences is easy as follows. First, install a custom Eclipse with the setup file as it is, i.e. without the preference. In that copy of Eclipse, select Window > Preferences > Oomph > Setup Tasks > Preference Recorder, check the Record into: checkbox and click the Open the recorder target file icon on the same line. Then, set other preferences as desired. After clicking Apply and Close, a pop-up like the one below shows the information for the key and value to configure.

oomph record preference

With this information, the key and value are:

  • key: /instance/com.sigasi.hdt.vhdl.Vhdl/vhdlVersion
  • value: V08

oomph edit preference

After adding the desired preferences and plugins, it’s time to save the setup file and use it with the Eclipse installer, as described here.

Project setup file

For a project setup file, it is recommended to start from our example: SigasiDemoProject.setup, which you can copy into your Oomph project and open for further customization. If you prefer to start from scratch, right-click your Oomph project and select New > Other… > Oomph > Setup Project Model, and check out the above example for the basic configuration.

Specify the location of your project and save the file. Now it is ready for use in the Eclipse installer.

We recommend to save project preferences in version control with the project, rather than in a project setup file. That way, changes to project settings get propagated to all team members effortlessly, and each revision of the project contains matching project settings. To that end, store .project, .library_mapping.xml and .settings of your project in version control.


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Configuring Your Design Environment

Choosing your VHDL and Verilog version

Sigasi Studio supports VHDL version 1993, 2002, 2008 and 2019 and Verilog (2005) and SystemVerilog (2012). You can select the default VHDL version to use in: Window > Preferences > Sigasi > VHDL. You can set the default Verilog version in: Window > Preferences > Sigasi > (System)Verilog.

Since Sigasi Studio 3.2, you can also set the language version per project, per folder and per file. In the Project Explorer, right click your project, folder or file; select Properties > VHDL Version or Properties > (System)Verilog Version and select the version via the dropdown menu.

When you change the language version of a file, only that file is affected. However, when you change the version of a folder, then everything in that folder will have the new language version. Any overrides in the folder and its sub-folders will be removed. When you are defining the language versions for a new project you should map from top (project root) to bottom (files).

The version information is stored in <project path>/.settings/com.sigasi.hdt.vhdl.version.prefs and <project path>/.settings/com.sigasi.hdt.verilog.version.prefs. We recommend you add this file to version control so you can share it with your team.

Notes:

  • VHDL libaries: Any new project that you create will have the Common Libraries (STD and IEEE) that correspond to your selected VHDL version. Your existing project will not be modified. If you want to update the Common Libraries for an existing project, right-click the project and select Library Mapping > Reset Common Libraries. Since Sigasi Studio 3.3, you will get a warning if your Common Libraries do not match the VHDL version of you VHDL file. You can use the proposed quick fix to resolve the issue.
  • If you want to compile VHDL 87 code, you should select the “1993” option. There are no checks to warn about constructs that were not supported in 1987, but that were introduced in 1993.
  • Sigasi Studio does not send the Common Libraries to an external compiler. It is expected that these libraries are pre-compiled.

Colors and Fonts

You can configure the code coloring by selecting Window > Preferences > Sigasi > VHDL > Syntax Coloring. For each class of semantic and syntactic elements, you can select the font, letter color, background color, style (bold, italic, underline, strike through).

Font size

Sometimes you want extra small fonts, so that you can fit more content on your screen. Another time you may want extra large fonts, so that you can use a beamer and your audience can see what you are doing.

Most fonts, including the font that is used by the editors, can be controlled in the preferences: Window > Preferences. Fonts are controlled in General > Appearance >Colors and Fonts. The font of the editors are in Basic > Text font.

Some fonts cannot be controlled in this preference page. These fonts are defined by general system settings, and are used for writing the menu names, the Project Explorer View and the Outline and Hierarchy Views. On Windows, you can change these fonts by changing your font settings in the Windows Control Panel. On Linux, these fonts are controlled by a settings file: ${HOME}/.gtkrc-2.0 . You can change the font by adding a line like:

gtk-font-name = "Sans 10"

You have to restart Sigasi Studio before these changes take effect.

Annotations Colors

Annotations are colors added on top of your text editor, and to the right of your text editor, in the scroll bar. The image below shows annotations for each occurrence of a certain data type. The color has been changed to bright green.

Annotations in Bright Green

You can change the color of annotations in Window > Preferences > General > Editors > Text Editors > Annotations. For the particular case of occurrence annotations, you want to modify the color for annotation type Occurrences. If more than one Occurrences type is displayed, you need the org.eclipse.xtext.ui.editor.defaultOccurrenceAnnotation. The others may refer to occurrences for Java or other plug-ins.

Tabs and Spaces

If you want to use spaces instead of tabs, you can set your indentation preferences in: Window > Preferences > General > Editors > Text Editors. Here you can select choose to Insert Spaces for Tabs and choose your preferred Displayed Tab Width.

The “Gutter”

The Gutter is the small area to the left of the editor view. It is used for displaying extra information about your code.

  • Line numbers: What line is this?
  • Quick Diff: Did this file change?
  • Folding: hiding pieces of code from view
  • Markers: error markers, warnings and bookmarks.

There is not much to configure about markers, but the other categories can be turned on or off.

Line numbers

To enable line numbers, right-click in the gutter and select Show Line Numbers.

Quick Diff

Instead of using a compare editor, you can enable quick diff support and see the changes within the text editor. This feature can be enabled via Window > Preferences > General > Editors > Text Editors > Quick Diff.

When you enable Quick Diff, you can see changes in the active editor with the version on disk (or the latest version in version control), by hovering the annotations in the gutter.

More info

Linting rules

You can choose the severity of linting rules in: Window > Preferences > Sigasi > VHDL > Errors/Warnings. Read more information about Linting and Quick Fixes.

Language

Eclipse is available in several languages, and you can install the language pack of your choice. Read more in this support article : Installing translations for Eclipse

Keyboard shortcuts

Sigasi Studio comes with a large number of Keyboard Shortcuts preconfigured. You can configure keyboard shortcuts (key bindings) in Window > Preferences > General > Keys. You can modify individual keyboard shortcuts or add new key bindings. There is also a preconfigured scheme for Emacs-like keyboard shortcuts.

After you have configured your keyboard shortcuts, you can export your settings and share them with your colleagues (or re-import them on another computer): To export, go to File > Export… > General > Preferences, and select Key Preferences. To import that file: File > Import… > General > Preferences.

Formatting

Formatting options for VHDL are documented in the VHDL Code Formatting section of the Editor manual.

Finding more options

[Not Documented Yet]
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License Key Management

Introduction

Sigasi Studio’s license key management system is based on the well known FlexNet (a.k.a. FlexLM) license manager. Sigasi Studio supports both node-locked and floating license keys. The Sigasi Studio edition is controlled by the license key.

Node locked licenses

If you have a node-locked license, you can enter your license key directly in Sigasi Studio.

  1. Open the Sigasi Studio License Key preference page: Window > Preferences > Sigasi > License Key
  2. Click Edit License File
  3. paste your key in the dialog

An example node-locked license looks like this. Note that the first line starts with INCREMENT

INCREMENT com.sigasi.hdt sigasi 2.0 18-nov-2012 uncounted \
        VENDOR_STRING="company:www.example.com;mac:10f2dd92c5ac;name:John \
        Doe;type:trial" HOSTID=ANY ISSUER=Sigasi ISSUED=21-Oct-2012 \
        START=21-Oct-2012 SIGN="0CCC 87EA 9BB6 256E 7D81 E49D B2A6 \
        E53D 1CA5 41D4 63DF 8671 5695 EF82 0E30 1028 732D DED3 0999 \
        FD11 8B97 42B0 7CF2 F51F 20A0 DA6E 7F54 9D64 FF29 49AB"

Floating licenses

If you have a floating license key, you need to configure both a license server and Sigasi Studio.

An example floating license looks like this. Note that the first line starts with SERVER or DAEMON:

DAEMON sigasi port=27001
SERVER your_server_name1 BD41FCF5DE27 27000
INCREMENT com.sigasi.hdt sigasi 2.0 18-nov-2012 4 \
        VENDOR_STRING="company:www.example.com;mac:10f2dd92c5ac;name:John \
        Doe;type:trial" HOSTID=ANY ISSUER=Sigasi ISSUED=21-Oct-2012 \
        START=21-Oct-2012 SIGN="0960 9728 7193 4DA5 15C2 3652 21E1 \
        EF82 1060 8FC1 9EA6 0C43 4842 C50B 684F E4DA 8EEF 37E9 5384 \
        8DF4 106C 52B4 EECE 0A69 CBAC 0CF2 47E2 00F2 A244 E22F"

Configuring Floating license in Sigasi Studio (FlexNet Client)

In order to use a floating license, Sigasi Studio needs to know how to contact the server. The license server can be configured in Sigasi Studio or using an environment variable.

Configure the license server in Sigasi Studio

In Sigasi Studio, navigate to the License Key preference page via: Window > Preferences > Sigasi > License Key. Next enter <portnumber>@<servername> in the License key path. For example:

27000@myserver.example.com

If you have redundant license servers, enter each of the license servers separated using “,”. It is recommended to specify the primary server first in the list. For example:

27000@myserver1.example.com,27000@myserver2.example.com,27000@myserver3.example.com

If you have multiple, non-redundant license servers, the servers should be separated using “:” on Linux and using “;” on Windows.

If you leave the License key path empty, Sigasi Studio will try to use an environment variable to find the license server.

Configure the license server in an environment variable

You can also set your license server via an environment variable instead of configuring it in Sigasi Studio. Both SIGASI_LM_LICENSE_FILE and LM_LICENSE_FILE are supported. When SIGASI_LM_LICENSE_FILE is set, LM_LICENSE_FILE is ignored.

Note that if you want to use an environment variable, you can not enter a path in the License Key preference page. The value on the License Key preference page has priority over environment variables.

Linux Example:

export SIGASI_LM_LICENSE_FILE=27000@myserver.example.com

For redundant license servers, the servers should be separated using “,”. It is recommended to specify the primary server first in the list. Example:

export SIGASI_LM_LICENSE_FILE="27000@myserver1.example.com,27000@myserver2.example.com,27000@myserver3.example.com"

License server setup

Download the FlexNet daemons

The version of the FlexNet daemons must be equal or higher than the FlexLM version of Sigasi Studio. The required version can be found in Sigasi Studio: Window > Preferences > Sigasi > License Key and look for the FLEXLM_VERSION line.

Check FlexLM version in Sigasi Studio

FlexNet version 11.16.4.0

FlexNet version 11.13.1.2

Customize License Server settings

By default, Sigasi license files use ports 27000 and 27001 on your license server. If these ports are already in use on the server, you can change the port numbers in the license file.

  • The port of the Sigasi daemon is set on the DAEMON line. For example: DAEMON sigasi port=27001, forces the Sigasi daemon to use port 27001.

  • The port of the FlexNet daemon is set on the SERVER line For example: SERVER your_server_name1 BD41FCF5DE27 27000, forces FlexNet to use port 27000. This is the port clients need to use to check out a license.

You can change the port numbers and your_server_name1 without breaking the signature. If you have a firewall, remember to open these ports for access.

Starting the FlexNet and Sigasi daemon on Linux

the easiest way to start the Sigasi FlexNet daemon is like this (on Linux)

#!/bin/sh
echo "Starting the Sigasi floating license server"
LOCATION=/home/flex/flexnet-sigasi
$LOCATION/lmgrd -c $LOCATION/sigasi.lic -l $LOCATION/debug.log

Starting the FlexNet and Sigasi daemon on Windows

  1. Download the Sigasi daemon (see above)

  2. Create a folder to hold the license manager software, in this example we will use D:\Sigasi\license.

  3. Unpack the zip file into the license folder (D:\Sigasi\license)

  4. Run the license configuration tool lmtools.exe as administrator.

  5. Save the license file supplied for Sigasi Studio to the license folder

  6. Using a text editor, edit the license file and replace your_server_name1 with the name of the machine you are using, for example: From: SERVER your_server_name1 74e50bb0911e To: SERVER Maple 74e50bb0911e

    Note: If you are not sure of the name of the machine you are using click on the System Settings tab of lmtools, where it is shown, see below:

  7. Click on the Config Services tab and fill in the following, use the browse button when available:

  • Service Name: Sigasi License Manager
  • Path to lmgrd.exe: D:\sigasi\license\lmgrd.exe
  • Path to license file: D:\sigasi\license\sigasi.lic
  • Path to the debug log file: D:\sigasi\license\debug.log Note: You will probably need to type the “Path to the debug log file”, in full as the file will not exist so you cannot browse to it.
  1. Ensure both the following check boxes are checked:
  • Use Services
  • Start Server at Power Up
  1. Now click the Save Service button, and click yes on the confirmation dialog.
  2. Switch to the Start/Stop/Reread tab and start the server.

The license server should now be configured correctly, and looks a bit like this one

Floating License options

Release a floating license

You can release a floating license (check a license in) without closing your Sigasi Studio application or Eclipse application. This is useful if you use Eclipse to edit other files than VHDL files, like C or Tcl.

First, make sure that all VHDL and Verilog files are closed and all VHDL and Verilog projects are closed. Next select Help > Sigasi > Floating license > Release Sigasi Floating Licenses

To get the license back (to check the license out), open the license dialog Help > Sigasi > Configure License… and press Apply.

How to block Sigasi Studio from checking out a license?

If you have configured an environment variable with the location of a FlexNet license server, you can instruct Sigasi Studio not to check out a license by setting the Sigasi Studio License key to none.

Checking out and releasing the XPRT license

If you have a license for Sigasi Studio XPRT , this is actually licensed as a com.sigasi.hdt.xl FlexNet feature combined with a com.sigasi.hdt.xl.doc FlexNet feature. The XL license is checked out as described above.

The XPRT license is checked out automatically in the following cases:

  • When you open the Block Diagram view
  • When you open the State Machine view
  • When you open the Class Hierarchy view
  • When you open the VUnit view
  • When you export documentation
  • When you click Help > Sigasi > Floating License > Check out Sigasi Studio XPRT license

The XPRT license can be released via: Help > Sigasi > Floating license > Release Sigasi Studio XPRT Floating Licenses.

Troubleshooting

If your license key does not work, the first things to check are:

  • Which version of the Sigasi license daemon are you using?
    Note: The Sigasi 2 daemon needs to be updated to run Sigasi 3. Otherwise you will see an License is not valid (Internal Flexlm Error) error message in the Sigasi Studio preference page.
  • Is the MAC address correct?
  • Since Sigasi Studio 4.3, on Linux Sigasi Studio uses the ip command to list MAC addresses instead of the now deprecated ifconfig command. If you’re using a version of Sigasi Studio older than 4.3 on Linux, you might need to install additional packages to obtain the ifconfig command.
    • On Arch, Debian or Ubuntu Linux, the “net-tools” package is needed.
    • On (Open)Suse the “net-tools-deprecated” package is needed.
  • Has the license expired?
  • Did you copy the license string exactly as it was sent to you?
  • Did you accidentally try to use a License Token as a license key?
    • A License Token is a 24 character string. You can use your license token to Activate Your License Key.
    • A License Key (or license file) looks like this:
INCREMENT com.sigasi.hdt sigasi 2.0 18-nov-2012 uncounted \
        VENDOR_STRING="company:www.example.com;mac:10f2dd92c5ac;name:John \
        Doe;type:trial" HOSTID=ANY ISSUER=Sigasi ISSUED=21-Oct-2012 \
        START=21-Oct-2012 SIGN="0CCC 87EA 9BB6 256E 7D81 E49D B2A6 \
        E53D 1CA5 41D4 63DF 8671 5695 EF82 0E30 1028 732D DED3 0999 \
        FD11 8B97 42B0 7CF2 F51F 20A0 DA6E 7F54 9D64 FF29 49AB"

Floating licenses

If your floating license server does not function properly, try the following steps:

  • Start the FlexLM daemon with the -z option to see what is going wrong

  • You can check that the FlexNet daemon is running as expected by following these steps:

    • Download the daemon zip file on the client machine
    • Run lmutil[.exe] lmdiag -c "<port>@<server>" -n
    • If the server is running correctly, you should see a description of the valid FlexNet features served by you license server.
  • Make sure the server name in the license key file is correct.

  • Make sure both the Sigasi and FlexNet daemon are the same version (i.e. from the same zip-file from the Sigasi download server). If you need to mix versions, the FlexNet daemon version should be equal to or higher than the Sigasi daemon version.

  • Firewall problems:

    • make sure that the port for the Sigasi FlexLM license daemon is open
    • you can force the port for the Sigasi license daemon by adding USE_SERVER and DAEMON sigasi port=to your license key
  • On Linux you might have to install lsb to avoid No such file or directory errors when starting lmgrd or other flexlm tools:

    • sudo apt-get install lsb-core
    • zypper in lsb
    • yum install lsb
    • yum install redhat-lsb.i686

    If the installation of lsb-core fails (e.g. on Debian Linux 10), try this workaround (as root):

    cd /lib64
    ln -s ld-linux-x86-64.so.2 ld-lsb-x86-64.so.3
    
  • The lmgrd license manager needs to have write access to the /usr/tmp/ path. If your system doesn’t have a directory /usr/tmp, you can make a link to /tmp (as root) :

    ln -s /tmp /usr/tmp
    
  • You can not have spaces in the daemon path.

  • Some users reported that specifying an arbitrary absolute path for the Sigasi daemon on Windows (e.g. DAEMON sigasi C:\\sigasi.exe port=27021) does not work. It only works if the Sigasi daemon is in the C:\Sigasi folder. Other users have reported that you are not allowed to have the directory name being the same as the daemon name. For example: c:\flexlm\sigasi\sigasi.exe is invalid, but c:\flexlm\vhdl_editor\sigasi.exe works fine.

  • Make sure the environment variable is correct: SIGASI_LM_LICENSE_FILE=<port number>@<servername>

  • Verify that your server meets the License Server System Requirements.
    If you try to run the daemon on an unsupported version of Windows, you will typically see this error message: CreateProcess error code: 0xc1 File= sigasi.exe.

  • You can easily check the status of your license via the License Key preference page : Preferences > Sigasi > License Key. At the bottom of this preference page you can see the type and expiration date of your license.

  • If you are accessing your license server through an SSH tunnel, try using 127.0.0.1 instead of localhost.

  • Sigasi Studio pre-emptively tries to check out certain license features. As a result, you might see warning message like this in your server log. These messages can be safely ignored.

9:14:47 (sigasi) UNSUPPORTED: "com.sigasi.hdt.custom" (PORT_AT_HOST_PLUS   ) testuser@testmachine  (License server system does not support this feature. (-18,327:10054 ""))
9:14:47 (sigasi) UNSUPPORTED: "com.sigasi.hdt.preview" (PORT_AT_HOST_PLUS   ) testuser@testmachine  (License server system does not support this feature. (-18,327:10054 ""))  

If the steps above do not help, feel free to send us an email and send us a screenshot of the license dialog with the error message.

Typical error messages

Check the content of the Sigasi License preference page via : Window > Preferences and Sigasi > License Key

No license

  • Is a valid license key path configured (or are valid environment variables used)?
  • Is the user trying to use a Sigasi Studio 3 license in Sigasi 2.x?

Invalid license key (inconsistent authentication code)

  • Did you correct the server name to the actual server name in the (floating) license key file?

Internal Flexlm Error

  • Check version number of FlexNet daemon, it is probably outdated. If not, check the daemon log on the license server

Invalid Message Received From License Server

  • Check the daemon log on the license server

Updating DACL Failed: “Service has been created but failed to update the DACL settings of FlexNet Licensing Service. It will give problem for accessing TS features. Check whether FlexNet Licensing Service is correctly installed or not and delete and create this service again.”

  • There seems to be a bug in lmtools.exe version 11 on some systems. You can work around this issue by configuring the (latest) Sigasi daemon with an older version of lmtools (Download here).

(lmgrd) license manager: can’t initialize:No SERVER lines in license file.
(lmgrd) License Path: “C:\FlexLM\sigasi\license.dat”
(lmgrd) FlexNet Licensing error:-13,66

  • If you see this error message. Double check you license file contains line with USE_SERVER.

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Sigasi Studio Talkback

Talkback is a Sigasi Studio service that automatically collects metadata about how Sigasi Studio is used and sends this metadata to Sigasi through a secured connection.

Why should I enable Talkback?

By enabling Talkback you help us improve Sigasi Studio:

  • Talkback lets us determine which features are heavily used. This helps in planning which kind of features are valuable for you as Sigasi Studio user, so that we can adjust our product roadmap.
  • Talkback collects performance statistics, that we can relate to the project sizes. Together with our in-house performance tests, this helps us keep the Sigasi Studio compiler and user interface fast.
  • Talkback helps us reduce software errors by collecting incident reports from a wide range of use cases.
  • The activation of Talkback is required to enable our free educational and open source licenses.
  • Talkback is automatic and less cumbersome than feedback surveys.

The end result is that you can use an always-improving Sigasi Studio.

How does Sigasi use this information

Sigasi uses the information transmitted by Talkback for marketing and product planning and development. We use it for deciding which features to develop and improve, for finding and fixing bugs and for finding and fixing performance issues.

What kind of information is sent through Talkback?

Talkback transmits meta-information about your project, operating system, Java Virtual Machine, tool usage, build performance, system statistics, license type, and incident reports (stack traces) that occur due to software errors. Talkback never transmits any HDL code. All transmissions are through an industry standard SSL secure connection.

In the Talkback transmissions, we identify your Sigasi/Eclipse workspace using a generated identifier (a standard Java universal unique identifier UUID).

Talkback stores all the information it transmits in a local log file, so that you can inspect it. The information is human-readable, in JSON (JavaScript Object Notation) format.

You can access the Talkback log to verify by clicking Window > Preferences > Sigasi > Talkback > Talkback log.

This log file is rotated for each new Sigasi Studio session or when the log reaches a certain size.

How do I enable or disable Talkback?

Talkback is always disabled by default. To enable Talkback, or to disable it later on, click Window > Preferences > Sigasi > Talkback and select or deselect the checkbox “Enable Talkback”.

What about my Firewall or Proxy?

Talkback uses the https protocol to send the information. If your firewall blocks SSL connections Talkback will not be able to send diagnostics. Your firewall should allow outgoing connections to https://talkback-sigasi.sigasi.com/.

Talkback does not support Proxies. If Talkback is unable to connect to our server directly because of your firewall or proxy server, you need to purchase a commercial license.

Features like Talkback are against our corporate policy, even if it is disabled. What can I do?

Please send us an email so that we can discuss a solution for your company.


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Capitalization of Identifiers

Although VHDL is not case-sensitive, it is recommended to always use the same capitalization when referring to the same declaration. Sigasi Studio warns when the capitalization of a reference differs from the capitalization of the declaration. Because external libraries can have different code styles, this linting only checks references in the same library as its declaration.

Capitalization can easily be fixed with a Quick Fix.

All capitalization issues in a file can be fixed in one click.

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

163/severity/<project>=IGNORE


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Check for Component/Entity Mismatch

Sigasi Studio gives a warning if a component declaration is not equal to its matching entity. You can easily fix this by applying the Quick Fix.

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

187/severity/<project>=IGNORE


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Check Header Comment

Sigasi Studio can check that the header comment matches a specified pattern. A header comment is a comment that starts at the first character of your file (no leading whitespace).

The check can be enabled in Preferences > Sigasi > VHDL > Naming conventions. The pattern can be set on the same page. More information on file header comment checking is available here.

Since Sigasi Studio 4.4, the raw string of the header comment is checked to allow for maximum compliance checking. This means that when a new line is matched, users should use \r?\n or the newly introduced \R to make sure the naming conventions work on all platforms.

Check header comments

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

188/severity/<project>=IGNORE


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Dead Code Linting Rule

Dead code is code that does not have any effect on your simulation or synthesis. Examples of dead code are signals that are never used or conditions that are never triggered.

Dead code does not bother the simulator or the synthesis tool. However, it consumes mental energy of anybody reading the code. People will try to figure out the purpose of a given statement and it may take a while before they realize that they are dealing with dead code. This makes it more expensive to review code and reuse code. In general, dead code is a form of technical debt that should be avoided.

Sigasi Studio flags some kinds of dead code:

  • unused declarations (signals, constants …) (rule 55):
architecture RTL of empty is
    signal   unused_s : bit;
    constant unused_c : bit := '0';
begin end;

a Quick Fix is available to help you remove unused declarations fast.

  • unused ports (rule 67) and generics (rule 68)
entity empty is
    generic(unused_g : bit);
    port   (unused_p : in bit);
end entity;

architecture RTL of empty is begin end;
  • unreachable statements (rule 79): if the Sigasi Studio analyzer can determine that a condition is always false, it will mark the if-statement because it contains dead code.
if true then
    v := v + 1;
else
    v := v - 1;
end if;
  • dead states in a state machine: a state is considered dead if it has no outgoing transitions (rule 71)
type t_state is (IDLE, START, RUN, DONE);
signal state: t_state;
  -- [omitted code]
  case state is
    when IDLE   => -- do something
        state <= RUN;
    when RUN    => -- do something
        state <= DONE;
    when DONE   => -- do something
        state <= IDLE;
    when others => -- do nothing
  end case;

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

55/severity/<project>=IGNORE

67/severity/<project>=IGNORE

68/severity/<project>=IGNORE

71/severity/<project>=IGNORE

79/severity/<project>=IGNORE


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Deprecated IEEE Packages and Non-Standard Packages

Some packages are widely spread but were never standardized by IEEE. Different vendors have shipped different versions, with incompatible implementations. These packages should not be used and are flagged as Deprecated IEEE packages.

use ieee.std_logic_arith.all
use ieee.std_logic_signed.all
use ieee.std_logic_unsigned.all

Instead, use the standard ieee.numeric_std package.

use ieee.numeric_std.all

The package ieee.std_logic_misc has the same problem of not being standardized by IEEE. Contrary to the packages above, there is no consensus on how to replace this package. Sigasi Studio flags this package as Non-standard package.

use ieee.std_logic_misc.all

Read more on IEEE packages in Deprecated IEEE Libraries.

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

8/severity/<project>=IGNORE

37/severity/<project>=IGNORE


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Filename Contains Primary Unit Name

Sigasi Studio can check that the filename contains the name of at least one of the design unit names inside that file. Note that this check is ignored by default. You can enable it in the VHDL Errors/Warnings preference page (Style Validation > Filename must contain primary name).

Check file name

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

189/severity/<project>=IGNORE


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Incomplete Port Maps and Generic Maps

Sigasi Studio warns about port maps and generic maps that are incomplete:
Port map uses default values. Missing optional actuals: yourport

Input ports and generics need to be assigned in your instantiation statement if they don’t already have a default value. If you don’t do this, you are writing illegal VHDL. Sigasi Studio will mark an error, and so will all other tools.

Input ports and generics with a default value, as well as output ports, do not need to be assigned explicitly. However, this is often not intended. For that reason, Sigasi Studio can warn you about this.

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

94/severity/<project>=IGNORE


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Linting Rules for Arrays

Sigasi Studio can check for a number of array / vector index-related problems:

  • Index out of range (rule 210).
architecture RTL of array_range_check is
    signal foo: bit_vector(7 downto 0);
    signal bar, baz: bit;
begin
    bar <= foo(8);   -- 8 is out of range "7 downto 0"
    baz <= foo(7);
end architecture RTL;
  • Slice has wrong direction (rule 211).

Slice ranges must use the same direction as the vector.

architecture RTL of array_range_check is
    constant iterations : integer := 8;
    signal foo: bit_vector(7 downto 0);
    signal bar, baz: bit_vector(0 to 7);
begin
    bar <= foo(0 to 7);   -- foo has a downto range
    baz <= foo;
end architecture RTL;

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

210/severity/<project>=IGNORE

211/severity/<project>=IGNORE


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Linting Rules for Instances

Sigasi Studio flags an error if the entity keyword is omitted in the instantiation of an entity.

Note that when instantiating a component, the keyword entity and the library name are not used.

architecture RTL of bar is
    component foo
        port(
            clk : in std_logic;
            rst : in std_logic
        );
    end component foo;
begin
    foo_inst_bad : work.foo              -- instance of entity foo requires keyword "entity"
        port map(
            clk => clk,
            rst => rst
        );

    foo_inst_correct : entity work.foo   -- correct instance of entity foo
        port map(
            clk => clk,
            rst => rst
        );

    foo_inst_comp : foo                  -- instance of **component** foo
        port map(
            clk => clk,
            rst => rst
        );
end architecture RTL;

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Linting Rules for Loops

Sigasi Studio can check for a number of loop-related problems:

  • Infinite loop missing a wait (rule 20). Note that infinite while and for loops will not be checked by this rule.
process
begin
   loop
      -- statements go here
   end loop;
end process;

process
begin
   loop
      -- statements go here
      wait for 1 ns;
   end loop;
end process;
  • Empty loop statement (rule 190): the loop body doesn’t contain any statements
for loopvar in  loop
   -- nothing going on here...
end loop;
  • for loops that will not execute due to a loop variable with a null range will be flagged with the Null range linting rule.

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

20/severity/<project>=IGNORE

190/severity/<project>=IGNORE


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Naming Conventions

On the Naming Conventions preference page (Window > Preferences > Sigasi > VHDL|Verilog/SystemVerilog > Naming Conventions) you can configure patterns to check the correct naming of your VHDL, Verilog, and SystemVerilog identifiers. Patterns are configured using regex syntax.

The above defines the Naming Conventions for the entire workspace. To specify Naming Conventions for a project instead of for the entire workspace, have a look at Naming Conventions per project.

Only names with a specified pattern are checked. Empty patterns are omitted.

Example: to enforce a style where all variables have a _v suffix, you would specify .*_v pattern in the Variable name field.

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

92/severity/<project>=IGNORE

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

2/severity/<project>=IGNORE


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Null or Empty Range

In VHDL, you can use ranges with to and downto. But, if you use the wrong direction, you get an empty range, which is usually not what you want.

signal foo: std_logic_vector(7 downto 0)  -- range of 8;
signal foo: std_logic_vector(7 to 0)      -- null range;

We have a lint check that warns about this, even if you use constants or some simple arithmetic.

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

1/severity/<project>=IGNORE

26/severity/<project>=IGNORE


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Order of Associations

Sigasi Studio gives a warning when the order of generics or ports in a map differs from the original generics or ports declaration order.

architecture RTL of dut is

   component my_comp port (
      clk  : in  std_logic;
      rst  : in  std_logic;
      inp  : in  std_logic;
      outp : out std_logic);
   end component;

begin
   assert iterations <= MAX_COUNT;

   i_comp_1: my_comp port map( -- associations should be kept in the same order as the declaration
      rst  => rst,
      clk  => clk,
      inp  => data_in(0), 
      outp => open
   );

   i_comp_1: my_comp port map(
      clk  => clk, 
      rst  => rst,
      inp  => data_in(0), 
      outp => open
   );

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

177/severity/<project>=IGNORE


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Positional Association in Instantiations

Most VHDL designers prefer named associations in port and generic maps in instantiations. This makes it a lot easier to spot wrong connections. By default, Sigasi Studio warns when positional associations are used. You can change the severity of this check via Preferences > Sigasi > VHDL > Errors/Warnings in the Instantiation statement validation section.

architecture RTL of dut is

   component my_comp port (
      clk  : in  std_logic;
      rst  : in  std_logic;
      inp  : in  std_logic;
      outp : out std_logic);
   end component;

begin
   i_comp_1: my_comp port map( -- positional associations not recommended
      clk,
      rst,
      data_in(0),
      open
   );

   i_comp_2: my_comp port map( -- named associations recommended
      clk  => clk,
      rst  => rst,
      inp  => data_in(0),
      outp => open
   );
end architecture RTL;

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

164/severity/<project>=IGNORE


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Quick Fix for Third-Party Libraries

If you are using vendor libraries from Intel or AMD/Xilinx (ISE or Vivado), you do not need to set up these libraries by hand. Sigasi Studio has a Quick Fix to do this for you. The missing library will be added to the Common Libraries of your project.

The library statement that tries to import a missing library (like altera) will have a yellow warning marker next to it. Click this marker and select Configure library altera (Altera). If the path to your Intel Quartus (or AMD/Xilinx ISE or Vivado) installation is not yet set, Sigasi Studio will ask to set the path now. You can always change these paths in Window > Preferences > Sigasi > Toolchains.

Note that for the AMD/Xilinx libraries we only map the packages with the component declarations. By default, all entity and architecture declarations are not mapped (excluded). This significantly reduces the time for a clean build. If you use direct entity instantiations, you can easily map the entities you need. See also Choose your version of the Vivado unisim.VCOMPONENTS package.

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

50/severity/<project>=IGNORE


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Redundant "others"

If a case statement contains all the possible choices (usually in an enumerated datatype), you can safely remove the when others clause. Sigasi Studio warns about this:

Case statement contains all choices explicitly. You can safely remove the redundant others.

case bits is
  when "00" => -- code
  when "01" => -- code
  when "10" => -- code
  when "11" => -- code
  when others => -- never reached: all cases are covered
end case;

There is some debate on this coding rule. However, the vast majority of synthesis tools do not take the others into account if all choices are enumerated. If the synthesis tool is set up to generate fault-tolerant hardware, the fallback state is the same as the reset state (for most synthesis tools). Check the manual of your synthesis tools and run some experiments. For more information, see VHDL case statements can do without the “others”.

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

13/severity/<project>=IGNORE


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Sensitivity List

VHDL requires a sensitivity list for each process or wait statements in the process body.

Sigasi Studio can warn about problems with your sensitivity list:

  • Presence of either a sensitivity list or one or more wait statements in a process (rule 38)

  • Incomplete sensitivity list (rule 72) (there is Quick Fix for this)

process(a  )
begin
       c <= a and b;
end process;
  • Superfluous signals in sensitivity list (rule 73)
process(a, b, c)
begin
       c <= a and b;
end process;
  • Duplicate signals in sensitivity list (rule 85)
process(a, b, b)
begin
       c <= a and b;
end process;

A sensitivity list should contain all signals that are read asynchronously in the process. For a combinatorial process, all signals read by the process should be in the sensitivity list. For a synchronous or clocked process, only the clock signal and an asynchronous reset signal (if present) should be in the sensitivity list. In synthesizable code, an incomplete sensitivity list will likely cause a synthesis-simulation mismatch. Even in test benches and purely behavioral code, an incomplete sensitivity list is often unintended and may lead to an unexpected simulation result. Most synthesis tools ignore the sensitivity list. In traditional workflows, only the synthesis warnings will give you a hint that your sensitivity list is incomplete. This report will be available only hours or even days after you have finished typing your code. Flagging this problem early can save a lot of time.

Since VHDL-2008, you can write process (all) to make sure you have all the necessary signals in the sensitivity list.

process(a, b)
begin
   c <= a and b;
end process;
process(clk)
begin
   if rising_edge(clk) then
      -- code
   end if;
end process;
process(clk, rst)
begin
   if rst = '1' then
      -- reset code
   elsif rising_edge(clk) then
      -- code
   end if;
end process;
process(all)
begin
   c <= a and b;
end process;

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

38/severity/<project>=IGNORE

72/severity/<project>=IGNORE

73/severity/<project>=IGNORE

85/severity/<project>=IGNORE


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Space Before the Physical Unit

If you type a numeric literal with a physical unit, there should be a space between the number and the unit.

    T := 25ns;  -- ILLEGAL, but accepted by ModelSim
    T := 25 ns; -- OK; according to VHDL language standard

Mentor Graphics’ ModelSim and QuestaSim accept the former (illegal) version. As a result, some VHDL designers got used to writing the incorrect version, producing code that is not portable to other simulators. Sigasi Studio accepts the ModelSim-style physical literals but warns about this.


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Superfluous Library Clause

The VHDL language reference manual states that:

Every design unit except package STANDARD is assumed to contain the following implicit context items as part of its context clause:

    library STD, WORK;
    use STD.STANDARD.all;

Hence, any extra library statement in your VHDL code that includes STD or WORK is pointless, as is any use clause that includes std.standard.all. Hardly anybody would type the use clause, but quite some people start all of their files with two extra library clauses.

It is good practice not to include use clauses for libraries STD and WORK. Sigasi Studio flags as warning if they appear.

library IEEE, STD, WORK;

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

49/severity/<project>=IGNORE


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Testing Equality of Booleans to true or false

When using booleans, it is unnecessary to test whether they’re equal to true (rule 185) or false (rule 186). Simply testing the boolean results in cleaner code.

signal valid: boolean;
-- some code omitted
if valid then
   -- ...
end if;

if valid = true then
   -- ...
end if;

if not valid then
   -- ...
end if;

if valid = false then
   -- ...
end if;

if valid /= true then
   -- ...
end if;

Note that the equals-false rule (186) is disabled (set to IGNORE) by default.

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

185/severity/<project>=IGNORE

186/severity/<project>=IGNORE


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Types in Expressions

Sigasi Studio flags an error if a type is used in an expression.

architecture RTL of type_in_expr is
    type t_foo is (one, two);
begin
    p : process is
    begin
        case t_foo is   -- a type cannot be used in an expression e.g. a case expression
            when one =>
        end case;
    end process p;
end architecture RTL;
architecture RTL of type_in_expr is
    type t_foo is (one, two);
    signal s_foo: t_foo;
begin
    p : process is
    begin
        case s_foo is   -- use a signal or variable of the required type in expressions
            when one =>
        end case;
    end process p;
end architecture RTL;

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Vector Width in Assignments and Port Maps

Sigasi Studio checks the vector size in assignments and port maps. This check works at type-time and takes the (symbolic) value of generics into account.

Sigasi Studio will not take into account the value assigned to a generic in instantiations. The reasoning behind this is explained here.

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

144/severity/<project>=IGNORE


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Verilog Ambiguous Reference

In Verilog, it is possible to reference identifiers from different files. However, if multiple files are declaring the same identifier there is no way to know which one should be used. Such cases will be marked as ambiguous references.

A possible reason you might be seeing these errors is that your project defines multiple top levels that have been mapped to the same library. More information about library mappings can be found here.

module inner;
    ...
endmodule
module inner(input x, y);
    ...
endmodule
module bad_code;
    inner inner_inst();
endmodule

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Verilog Assignment Patterns

Sigasi Studio has several checks on Verilog assignment patterns.

Default member must be last

Concrete assignments must precede more general assignments. Otherwise, some of those assignments might be ignored (rule 28). In particular:

  • for arrays, default must be at the end of the list
  • for structures, default must be at the end, but type-default must be after the particular member assignments
module badcode;
    int a[3:0] = '{0: 5, default: 0, 3: 1};
   
    typedef struct {
        int x;
        int y;
        real radius;
    } circle_t;
   
    circle_t b = '{default: 0, x:1};
   
    circle_t c = '{default: 0, real: 0.0};
   
endmodule

module goodcode;
   
    int a[3:0] = '{0: 5, 3: 1, default: 0};
   
    typedef struct {
        int x;
        int y;
        real radius;
    } circle_t;
   
    circle_t b = '{x:1, default: 0};
   
    circle_t c = '{real: 0.0, default: 0};
endmodule

Only one default member expression is allowed

Sigasi Studio flags an error when expressions have multiple default assignments (rule 29). In particular:

  • arrays cannot have multiple default assignments
  • structures cannot have multiple default assignments or multiple type-default assignments
module badcode;
    int a[3:0] = '{default: 1, 0: 2, default: 3};        // multiple default assignments
    
    typedef struct {
        int x;
        int y;
        real radius;
    } circle_t;
    
    circle_t b = '{default: 0, radius: 1.0, default: 0}; // multiple default assignments
    
    circle_t c = '{int: 0, radius: 1.0, int: 0};         // multiple *type*-default assignments
endmodule

module goodcode;
    int a[3:0] = '{0: 2, default: 3};
    
    typedef struct {
        int x;
        int y;
        real radius;
    } circle_t;
    
    circle_t b = '{radius: 1.0, default: 0};
    
    circle_t c = '{radius: 1.0, int: 0};
endmodule

Overwritten type key in assignment pattern

Sigasi Studio flags a warning for duplicate type member keys in assignment patterns (rule 30). This is not an error according to the language reference manual, but the last used type key overwrites previously matched members, making the code confusing and hard to maintain.

module uglycode;
    struct { int x, y; } a = '{int: 0, int: 1};
    int b[10] = '{int: 0, int: 1};
endmodule

module goodcode;
    struct { int x, y; } a = '{int: 1};
    int b[10] = '{int: 1};
endmodule

Duplicate member key in structure assignment pattern

Sigasi Studio flags an error for duplicate members/index keys in assignment patterns (rule 31). Each member/index key can occur only once.

module badcode;
	struct { int x, y; } a = '{x: 0, y: 0, x: 0};
	int b[10] = '{5: 1, 5: 2, default: 0};
endmodule

module goodcode;
	struct { int x, y; } a = '{x: 0, y: 0};
	int b[10] = '{5: 1, default:0};
endmodule

Mixed named and ordered notation in assignment pattern

Sigasi Studio flags an error when an assignment contains a mix of ordered and named elements (rule 32).

module badcode;
    // Mix of ordered and named associations: not correct
    struct { int x, y; } a = '{0, y: 1};
    int b[4] = '{0, 1, 2:5, 3:7};
endmodule
module ok_code;
    // Place binding: correct but may be harder to read, particularly with many elements
    struct { int x, y; } a = '{0, 1};
    int b[4] = '{0, 1, 5, 7};
endmodule
module goodcode;
    // Name binding: esay to understand and maintain
    struct { int x, y; } a = '{x: 0, y: 1};
    int b[4] = '{0: 0, 1: 1, 2: 5, 3: 7};
endmodule

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

28/severity/<project>=IGNORE

30/severity/<project>=IGNORE

31/severity/<project>=IGNORE

32/severity/<project>=IGNORE


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Verilog Case Statements

Sigasi Studio has a number of checks on Verilog case statements.

Case statement does not cover all cases

A case statement should cover all options, either enumerating all options explicitly or with a default clause (rule 8). This rule is checked for enum types only, not for scalar or vector types.

module badcode(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)                      // Error: case `INIT` is missing
            IDLE    : state = START;
            START   : state = READY;
            READY   : state = IDLE ;
        endcase
    end
endmodule

module bettercode(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)
            INIT    : state = IDLE ;
            IDLE    : state = START;
            START   : state = READY;
            READY   : state = IDLE ;
        endcase
    end
endmodule

Note that Sigasi Studio also warns for case statements without a default clause

Default clause has to be the last item in a case statement

The default clause should be at the end after all the other options (rule 15). Sigasi Studio flags a warning if that is not the case.

module badcode(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)
            IDLE    : state = START;
            START   : state = READY;
            default : state = IDLE ;      // The `default` clause must be at the end
            READY   : state = IDLE ;
        endcase
    end
endmodule

module goodcode(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)
            IDLE    : state = START;
            START   : state = READY;
            READY   : state = IDLE ;
            default : state = IDLE ;
        endcase
    end
endmodule

This rule also applies to generate case statements, e.g.

module bad_example#(parameter WIDTH=8);

    generate
    case (WIDTH)
        default:  // The `default` clause must be at the end
            begin // others - carry look-ahead adder
                adder_cla #(WIDTH) x3(co, sum, a, b, ci);
            end
        1: begin // 1-bit adder implementation
            adder_1bit x1(co, sum, a, b, ci);
        end
        // other cases
    endcase
    endgenerate

endmodule

Case statement can only have one default clause

A case statement can only have one default clause (rule 16). A warning is flagged if more than one default clause is present.

module badcode(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)
            IDLE    : state = START;
            START   : state = READY;
            READY   : state = IDLE ;
            default : state = IDLE ;      // Error: two `default` clauses
            default : state = START;
        endcase
    end
endmodule

module goodcode(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)
            IDLE    : state = START;
            START   : state = READY;
            READY   : state = IDLE ;
            default : state = IDLE ;
        endcase
    end
endmodule

This rule also applies to generate case statements, e.g.

module bad_example#(parameter WIDTH=8);

    generate
    case (WIDTH)
        default:  // Error: two `default` clauses
            begin // others - carry look-ahead adder
                adder_cla #(WIDTH) x3(co, sum, a, b, ci);
            end
        1: begin // 1-bit adder implementation
            adder_1bit x1(co, sum, a, b, ci);
        end
        // other cases
        default:  // Error: two `default` clauses
            begin // others - carry look-ahead adder
                adder_cla #(WIDTH) x3(co, sum, a, b, ci);
            end
    endcase
    endgenerate

endmodule

Default clause missing from case statement

Sigasi Studio flags a warning for case statements without a default clause (rule 40). While a case statement without a default branch is syntactically correct, many guidelines recommend attaching a default branch, even if the case statement is completely defined. This ensures no latch would be inferred during synthesis if the case is incomplete (sometimes difficult to judge, esp with casex/casez semantics or larger widths).

module rather_ok_code(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)
            INIT    : state = IDLE ;
            IDLE    : state = START;
            START   : state = READY;
            READY   : state = IDLE ;
            // no default branch
        endcase
    end
endmodule

module goodcode(input clk);
    typedef enum {INIT, IDLE, START, READY} t_state;
    t_state state;

    always @(posedge clk) begin
        case (state)
            INIT    : state = IDLE ;
            IDLE    : state = START;
            START   : state = READY;
            READY   : state = IDLE ;
            default : state = IDLE ;
        endcase
    end
endmodule

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

8/severity/<project>=IGNORE

15/severity/<project>=IGNORE

16/severity/<project>=IGNORE

40/severity/<project>=IGNORE


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Verilog Checks on Initialization

Initializing registers at the point of declaration may be tricky. If your (System)Verilog code is not going to be synthesized (e.g. testbench), it is completely acceptable. FPGA synthesis tools may also take initialization into account, so depending on your FPGA project, initializing registers when they are declared in the code may be a viable (or even preferred) option.

ASIC synthesis tools however will ignore initialization as in the first example, which may lead to a mismatch between synthesis and simulation. In such a case, initialization should be done using resets, as in the second example.

By default, Sigasi Studio flags a warning for register initialization at the point of the declaration. For FPGA projects it may be desirable to turn the warning off, whereas for ASIC projects one may want to raise the severity to error.

module fpga_only(input clk, input rst, input ii, output logic oo = 1'b0);
    logic sig = 1'b0;

    // ...
endmodule
module asic_fpga(input clk, input rst, input ii, output logic oo);
    logic sig;

    always @(posedge clk) begin
        if (rst == 1) begin
            sig = 1'b0;
            oo  = 1'b0;
        end
        else begin
            // ...
        end
    end
endmodule

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

35/severity/<project>=IGNORE


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Verilog Class Item Visibility

In Verilog class methods and class properties can be declared as local or protected to restrict their access. Sigasi Studio will flag attempted accesses that violate these restrictions as errors.

Local

local methods and properties can only be accessed from within the class itself.

class my_class;
    
    local int secret = 42;
    
    function int get_secret();
        return secret;
    endfunction
    
endclass

module bad_code;
    
    my_class inst = new();
    int x = inst.secret;
    
endmodule

Protected

protected methods and properties can only be accessed from within the class itself, or from any of its subclasses.

class my_class;
    
    protected int secret = 42;
    
endclass

class my_sub_class extends my_class;
    
    function int get_secret();
        return secret;
    endfunction
    
endclass


module bad_code;
    
    my_sub_class inst = new();
    int x = inst.secret;
    
endmodule

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Verilog Coding Style

Sigasi Studio has a number of checks on Verilog and SystemVerilog coding style.

Empty loops and conditional branches

While occasionally intended, this construction is confusing, and often the result of a typo. Sigasi will flag a warning if an empty block is found (rule 1). In RTL code for synthesis, empty conditional branches in sequential code can cause unwanted latch generation. There may be a couple of reasons why an empty block is present in your code:

  • It is an unintentional omission and should be fixed to prevent unexpected behavior.
  • Some functionality is not yet, or never will be, supported. In this case, a $fatal (or similar) system task should be called.
  • It is intentionally blank. In this case, a comment should clarify the reason why.

File name does not match design unit

It is recommended that the base name of the filename is the same as the name of the design unit (e.g. module) in the file (rule 17). Sigasi Studio flags a warning if that is not the case.

E.g. module my_module should be in a file named my_module.v or my_module.sv .

In a file with multiple design units (which is not recommended), this rule is not active.

File contains multiple design unit

It is recommended that a Verilog file contains only one design unit (rule 18). Sigasi Studio flags a warning if that is not the case.

Verilog code line too long

For legibility, it is recommended to keep lines of code short (rule 20). Sigasi Studio flags a warning if a code line is longer than a certain length. The maximum length is set to 120 characters by default, but this can be changed in the project linting settings (${project_location}/.settings/com.sigasi.hdt.verilog.linting.prefs). E.g.:

20/params/max_line_length/<project>=123

Tabs are not allowed

While this may potentially be controversial, TABs are forbidden in the majority of coding standards in the HDL domain with the motivation of code not looking the same regardless of the editor/settings used. This check is off by default but it can be enabled in the workspace or project linting settings (rule 21).

File header comment does not match required pattern

Many coding standards require the presence of a header comment in every file, matching a certain format. Sigasi Studio can check whether the file header comment matches a pattern (rule 22). By default, the pattern is empty which disables this check. The pattern can be configured through Window > Preferences > Sigasi > (System)Verilog > Naming conventions > File header and uses the regex syntax. More information on file header comment checking is available here.

Report encrypted regions

Starting with Verilog 2005, regions of Verilog and SystemVerilog files may be encrypted to protect intellectual property. Sigasi obviously won’t check the content of these regions. Optionally, Sigasi can flag the presence of encrypted regions in your code (rule 44). This rule is off by default (i.e. set to IGNORE) but can be enabled (as info, warning, or error) as required.

Multiple statements per line

For readability, each statement should be on a separate line. Sigasi Studio will flag a warning if a line of code contains multiple statements (rule 47).

module rule47;
    reg A, B, C, D, K, M;
    reg EN;

    assign A = B & C, D = K & M;    // multiple statements in one line: less readable

    assign A = B & C;               // one statement per line: more readable
    assign D = K & M;

    always@(*)
        if(EN==1'b1) begin
            A = B & C; D = K & M;   // multiple statements in one line: less readable

            A = B & C;              // one statement per line: more readable
            D = K & M;
        end
		
endmodule

Sigasi Studio will flag a warning if a parameter list has a trailing comma (rule 52). Most EDA tools will treat a trailing comma as a syntax error.

module ugly #(WIDTH = 16 , ) (
    // ...

module nice #(WIDTH = 16) (
    // ...

Regular expressions compatibility

Naming conventions in Sigasi use RE2/J regular expressions. RE2/J expressions mitigate potential performance problems that are caused by some shapes of regular expressions using the regular Java regular expression engine. Sigasi will warn if a naming convention rule contains a regular expression that is incompatible with RE2/J (rule 58).

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

1/severity/<project>=IGNORE

17/severity/<project>=IGNORE

18/severity/<project>=IGNORE

20/severity/<project>=IGNORE

21/severity/<project>=IGNORE

22/severity/<project>=IGNORE

44/severity/<project>=IGNORE

52/severity/<project>=IGNORE


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Verilog Duplicate Declaration

In Verilog, you are not allowed to declare the same identifier multiple times within the same scope. All duplicate declarations will be marked as errors.

module bad_code;
    parameter p = 0;
    parameter p = 1;
endmodule
parameter p = 0;

module good_code;
    parameter p = 1;
endmodule

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Verilog Functions

Non-blocking assignments are not allowed in functions

A non-blocking assignment (<=) is not allowed in a (System)Verilog function. While syntactically correct, it will generally not lead to the desired behavior, and will likely cause synthesis-simulation mismatch. Sigasi Studio flags an error if a blocking assignment is used in a function (rule 41).

A good fix to correct the problem is to replace non-blocking assignments (<=) with blocking assignments (=)

module badcode;
	function plus_one;
		input integer a;
		begin
			plus_one <= a + 1;  // Incorrect: non-blocking assignment
		end
	endfunction
endmodule

module goodcode;
	function plus_one;
		input integer a;
		begin
			plus_one = a + 1;   // Correct: blocking assignment
		end
	endfunction
endmodule

Function prototype has implicit return type

SystemVerilog function prototypes (pure virtual functions) should have a return type. Sigasi Studio flags a warning for function prototypes without return type (rule 10).

virtual class badclass;
    pure virtual function myfunc(input bit[31:0] data);           // return type missing
endclass

virtual class goodclass;
    pure virtual function integer myfunc(input bit[31:0] data);
endclass

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

10/severity/<project>=IGNORE


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Verilog Inputs

Although the input direction is taken by default, it is preferable to explicitly specify the direction to improve readability and make the code self-documenting.

module bad_example;

	function int my_func(int a, b);          // bad: direction of a and b omitted
		return a+b;
	endfunction
	
	task my_task(int a, b);                 // bad: direction of a and b omitted
	begin
		$display(a);
		$display(b);
	end
	endtask
	
endmodule
module good_example;

	function int my_func(input int a, b);   // good: direction of a and b specified
		return a+b;
	endfunction
	
	task my_task(input int a, b);          // good: direction of a and b specified
	begin
		$display(a);
		$display(b);
	end
	endtask
	
endmodule

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

14/severity/<project>=IGNORE


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Verilog Keywords in VHDL

When choosing entity and port names in VHDL, it is recommended not to use (System)Verilog keywords. This will prevent problems if the VHDL entity ever has to be integrated into a mixed VHDL/Verilog project. Sigasi Studio will warn if a (System)Verilog keyword is used as an entity name.

entity always is port( -- always is a Verilog keyword: not recommended!

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

192/severity/<project>=IGNORE


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Verilog Out-of-bound Method Declarations

An out-of-block method declaration signature should match its prototype declaration’s signature. Sigasi Studio flags an error if the prototype and the implementation signatures have a:

  • different subroutine form (task or function)
  • different return type, if it is a function
  • different arity or any argument has a:
    • different name
    • different direction
    • mismatched type

If an argument default value is present in an out-of-block method declaration but is missing in the prototype, or default values are not syntactically identical, a warning message is reported (rules 77, 78).

Errors are also reported for a missing prototype for out-of-bound definitions and missing or duplicated definitions for an extern method prototype.

class C;
    extern task proto_only();       // missing definition
    extern task who_am_i();
    extern function bit bad(input int a, b, c, d, e = 2 + 3);

    extern function int good(input int a, output string b);
endclass

function C::who_am_i();             // should be a task
    // ...
endfunction

function C::no_proto();             // missing prototype
    // ...
endfunction

function logic C::bad(              // should return bit
    output int a,                   // should be input
    input integer b,                // should be int
    input int si,                   // should be 'c'
    input int d = 4,                // should have no default value
    input int e = 5                 // should be same value as prototype: 2 + 3
);
    // ...
endfunction

function bit C::bad(ref x, y);      // completely different signature, duplicate definition
    // ...
endfunction

function int C::good(input int a, output string b);
    // ...
endfunction

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

90/severity/<project>=IGNORE

91/severity/<project>=IGNORE


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Verilog Overridden Method Signatures

A virtual method signature should match the overridden method signature in the superclass. Sigasi Studio flags an error if the signatures have a:

  • different subroutine form (task or function)
  • different return type, if it’s a function
  • different arity or any argument with a:
    • different name
    • different direction
    • mismatched type

If an argument default value is present in one method and is missing in the other one, an info message is reported (rule 67).

interface class A;
    pure virtual task who_am_i();
    pure virtual function bit bad(input int a, b, c, d);
    pure virtual task too_bad(input int a, b, c, d);

    pure virtual function A good(input int a, output string b);
endclass

class B implements A;
    virtual function who_am_i();      // should be a task
        // ...
    endfunction

    virtual function logic bad(       // should return bit
        output int a,                 // should be input
        input integer b,              // should be int
        input int si,                 // should be 'c'
        input int d = 4               // should have no default value

    );
        // ...
    endfunction

    virtual task too_bad(ref x, y);   // completely different signature
        // ...
    endtask

    virtual function B good(input int a, output string b);
        // ...
    endfunction
endclass

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

67/severity/<project>=IGNORE


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Verilog Parameters

Sigasi Studio validates the use of parameters in (System)Verilog.

Parameters without a default value

Sigasi Studio flags a warning if a parameter is declared without a default value (rule 19). Syntactically this is allowed since the instantiating modules should provide the value to the instance parameter. However, it is undesirable since it makes the definition dependent on a particular hierarchy and limits code reusability. In addition, it is creating elaboration errors when attempting to use such modules as a top-level.

module badcode;
	parameter P;
	initial
	    $display(P);
endmodule

module goodcode;
	parameter P = 0;
	initial
	    $display(P);
endmodule

Parameters width mismatch

Sigasi Studio flags an error if a parameter with a defined width is declared is assigned a value of differing width (rule 48).

parameter int         p = 'h764321098;   // Number of bits set a04a (35) wider than the expected bit width (32)

parameter signed [36] q = 'h764321098;

Empty parameter not allowed

The Verilog standard does not allow empty parameters (rule 53).

module dut # (parameter WIDTH = 42, ) (input clk); endmodule; // dangling comma is not allowed

module dut # (parameter WIDTH = 42 ) (input clk); endmodule;

Empty parameter overrides not allowed

The Verilog standard does not allow empty parameter overrides (rule 54).

module test;
    sub#(8, 16, ) inst(); // dangling comma is not allowed
endmodule

module test;
    sub#(8, 16 ) inst();
endmodule

Local parameter has to be initialized

The Verilog standard requires that local parameters are initialized (rule 69).

localparam p;             // initialization missing

localparam p = 1;

Local parameter cannot be overridden

The Verilog standard does not allow the overriding of local parameters (rule 70).

module name(
    input clk,
    input rst
);
    localparam int test = 42;

    defparam test = 0;    // override not allowed
endmodule : name

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

19/severity/<project>=IGNORE

48/severity/<project>=IGNORE

53/severity/<project>=IGNORE

54/severity/<project>=IGNORE


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Verilog Port and Parameter Associations

Sigasi Studio has several checks on Verilog port and parameter associations.

Named parameter and port connections have to be used for all instances with many parameters / ports

A long list of positional parameters or port connections is difficult to read and maintain. Therefore, Sigasi Studio warns if a list of positional connections is longer than 3 items (rules 24 and 26). If the number of associations is larger than 3, named connections should be used.

module sub(input clk, arst, enable, data, output reg data_out);
    always @(posedge clk or negedge arst)
    if (~arst)
        data_out <= 1'b0;
    else if (enable)
        data_out <= data;
endmodule

module badtop;
    logic clk, arst, en, a, b;
    sub sub_inst(clk, arst, en, a, b); // 5 ordered associations: difficult to read and maintain
endmodule

module goodtop;
    logic clk, arst, en, a, b;
    sub sub_instance (
        .clk(clk),
        .arst(arst),
        .enable(enable),
        .data(a),
        .data_out(b)
    );
endmodule

The maximum number of 3 items is a default value, it can be changed in the project linting settings (${project_location}/.settings/com.sigasi.hdt.verilog.linting.prefs). E.g.:

24/params/max_ordered_port_connections/<project>=4
26/params/max_ordered_parameter_overrides/<project>=2

Named and positional associations cannot be mixed

Sigasi Studio flags an error when attempting to mix named and positional port or parameter associations (rule 25).

module sub#(PARAM_1=2, PARAM_2=3) ();
endmodule

module badtop;
    // Syntax error: mix of named (`PARAM_1`) and positional (`3`) association
    sub#(.PARAM_1(2), 3) sub_inst();
endmodule

module ok_top;
    // All associations are positional: OK but harder to understand and maintain
    sub#(2, 3) sub_inst();
endmodule

module goodtop;
    // All associations are named: best practice
    sub#(.PARAM_1(2), .PARAM_2(3)) sub_inst();
endmodule

Unresolved formal names

Sigasi Studio flags an error for named port and parameter connections if the instantiated module doesn’t have ports with these names.

module sub(i1, i2, o1);
    parameter WIDTH = 8;
    input[WIDTH-1:0] i1, i2;
    output[WIDTH-1:0] o1;
endmodule

module badtop;
    logic aa, bb, cc;
    // parameter `HEIGHT` and ports `a`, `b`, `c` do not exists in module `sub`
    sub#(.HEIGHT(4)) sub_inst(
        .a(aa),
        .b(bb),
        .c(cc)
    );
endmodule

module goodtop;
    logic aa, bb, cc;
    sub#(.WIDTH(4)) sub_inst(
        .i1(aa),
        .i2(bb),
        .o1(cc)
    );
endmodule

Duplicate port and parameter connections

Sigasi Studio flags an error for duplicate named port and parameter connections (rule 37).

module sub#(WIDTH=8) (input[WIDTH-1:0] i1=1'b0, i2, output[WIDTH-1:0] o1);
endmodule

module badtop;
    logic a, b, c;
    // parameter `WIDTH` and port `i1` are connected twice
    sub#(.WIDTH(4), .WIDTH(6)) sub_inst(
        .i1(a),
        .i1(b),
        .o1(c)
    );
endmodule

module goodtop;
    logic a, b, c;
    // parameter `WIDTH` and port `i1` are connected once
    sub#(.WIDTH(4)) sub_inst(
        .i1(a),
        .o1(c)
    );
endmodule

Missing actuals for formals that have no default value

Sigasi Studio flags a warning for missing port or parameter connections if the ports or parameters don’t have a default value (rule 38).

module sub
 #(LHS, RHS=0)
 (input[LHS:RHS] i1=1'b0, i2, output[LHS:RHS] o1);
endmodule

module badtop;
    logic[7:0] x;
    // parameter `LHS` and port `i2` don't have a default value so they must be connected
    sub sub_inst(.o1(x));
endmodule

module goodtop;
    logic[7:0] x;
    wire[7:0] y;
    sub#(.LHS(7)) sub_inst(
         .i2(y),
         .o1(x)
    );
endmodule

Excessive number of actuals in ordered notation

Sigasi Studio flags an error if the number of positional parameters or port connections is larger than the number of parameters or ports of the instantiated module (rule 39).

module sub#(WIDTH=8) (input[WIDTH-1:0] i1=1'b0, i2, output[WIDTH-1:0] o1);
endmodule

module badtop;
    logic a, b, c, d;
    // Expecting 1 parameter connection and 3 port connections instead of 2 and 4
    sub#(4, 6) sub_inst(a, b, c, d);
endmodule

module goodtop;
    logic a, b, c;
    sub#(4) sub_inst(a, b, c);
endmodule

Note that if there are too few positional parameters or port connections, an error for missing connections will be flagged.

Named connections are not allowed with blank ports

If an instantiated module contains a null port, the instantiation must use port association by order and not by name (rule 56).

module sub(
	input clk,
	,             // this is a *null port*
	input rst
);
endmodule

module badtop;
    sub sub_instance(
        .clk(clk),
        .rst(rst)
    );
endmodule

module goodtop1;
    sub sub_instance(
        ,clk
        ,
        rst
    );
endmodule

module goodtop2;
    sub sub_instance(
        clk,
        foo,
        rst
    );
endmodule

Project specific setting of these rules

These rules can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

24/severity/<project>=IGNORE

26/severity/<project>=IGNORE


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Verilog Processes

(System)Verilog always constructs without an event control statement at the top cannot be synthesized. Additionally, they would activate in random order at the moment 0 at beginning of a simulation.

Sigasi Studio flags a warning for always blocks without an event control statement at the start.

A good way to correct this description is to place the timing control statement at the top.

module test(clk, data_in, data_out);
    input clk;
    input[3:0] data_in;
    output reg[3:0] data_out;
    
    always
    begin
        data_out <= data_in;
        @(posedge clk); // Timing control not at the top of 'always'
    end
endmodule

module test(clk, data_in, data_out);
    input clk;
    input[3:0] data_in;
    output reg[3:0] data_out;
    
    always @(posedge clk)
       data_out <= data_in;
    
endmodule

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

27/severity/<project>=IGNORE


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Verilog reg and logic Datatype

In SystemVerilog, the reg datatype is deprecated. It is recommended to use the logic datatype instead.

Sigasi Studio flags a warning when the reg datatype is used in SystemVerilog.

A Quick fix is available to convert reg into logic.

module my_module;
    reg   deprecated;
    logic good;
endmodule

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.verilog.linting.prefs:

3/severity/<project>=IGNORE


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VHDL Coding Style Rules

Sigasi Studio has a number of checks on VHDL coding style.

Extended identifier contains whitespace

Sigasi Studio flags an info message when using extended identifiers which contain whitespace (rule 228). Particularly in mixed-language designs, these identifiers may cause problems in Verilog and SystemVerilog as they use whitespace to mark the end of an extended identifier.

signal \foo bar\ : std_logic  -- identifier with spaces: not recommended!

Project specific setting of this rule

This rule can be disabled for your project, or its severity can be modified in the project linting settings.

Manual configuration in ${project location}/.settings/com.sigasi.hdt.vhdl.linting.prefs:

228/severity/<project>=IGNORE


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VHDL Language Version

Sigasi Studio flags an error if a mismatch exists between the selected VHDL language versions of a project, VHDL common libraries, and individual design files.

Applying the associated quick fix will upgrade the version of the project, or - if it’s already set up correctly - it’ll upgrade the version of the file with the outdated version. The Common Libraries will automatically be updated to the upgraded version.

In Sigasi Studio, you can set the version of the VHDL language for your project and individual files. The setting for individual files is only intended for compatibility with legacy code. Setting a higher VHDL version on a design file than the VHDL version of the project is not supported and will cause this error to appear.


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This single page manual was generated on 2023-05-26.