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The source code to the Voss II Hardware Verification Suite
C Verilog Tcl Yacc Haskell Makefile Other
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IDVII/src/fl Enhanced the help extraction code to get the names of the inputs/outputs Mar 25, 2020
demos Initial version Jan 28, 2020
modes Added functionality to handle vim-fl interface if you use vim in a mode Mar 30, 2020
src Enhanced the help extraction code to get the names of the inputs/outputs Mar 25, 2020
NOTICE Added all the Apache 2.0 license stuff. Feb 4, 2020

Voss II

Voss II is a software suite for describing and reasoning about circuits. Circuits, and properties about them, are described in a functional language called fl.

Fl is a statically typed language with call-by-need semantics (also known as lazy evaluation) and binary decision diagrams built right into the language itself.

Voss II has been tested and found to work on Debian, Ubuntu, Fedora, Red Hat and OpenSUSE. If you're using it on another distribution, we'd love to hear from you!

Introduction to VossII

There is a "Getting Started with VossII and fl" tutorial in the doc/fl_tutorial directory (you can do firefox doc/fl_tutorial/fl_tutorial.html or your choice of browser to see it)

There is also a more extensive User's Guide


Download our pre-built binaries and unpack them to your directory of choice, then put /bin in your search path and you will be able to run the fl interpreter by simply invokng fl. Note that you need the /bin in your search path for the Verilog reader to work, and it must be earlier than any paths containing other versions of yosys!

Voss II depends on Tk for its graphical bits. If the fl interpreter dies with an angry message about not being able to find wish, you need to install it:

  • On Ubuntu/other Debian-based
    sudo apt install tk
  • On Fedora/Red Hat
    sudo yum install tk
  • On SUSE
    sudo zypper install tk

Building (on Ubuntu/Debian)

If you want to build your own libraries you will first need to install some build dependencies:

sudo apt-get install gcc g++ doxygen flex bison gawk \
                     libz-dev tcl-dev tk-dev libc6-dev \
                     clang libreadline-dev python3 imagemagick pandoc

Then, from the root of the VossII repository (assuming you've already cloned it), run:

make -C src install

This will build Voss II and install it into the repository root directory. If you want to build a distributable binary package, you should install run:

make -C src clean_package

This will create a file voss.tar.bz2 in the repository root directory.

Finally, if you just want to build a Voss II package in a pristine environment, without having to sully your system with a bunch of dependencies, you can use Docker to build voss.tar.bz2 instead:

make -C src docker_package

If you're not a member of the docker group on your system, you will need to run the above command as root.

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