Collection of SystemVerilog exercises for the School of Digital Circuit Synthesis

Not a day without a line in Verilog

Collection of tasks of increasing complexity

Yuri Panchul, 2021-2024

Installation instructions

The tasks can be solved with any Verilog simulator that supports SystemVerilog. And also with the free Icarus Verilog simulator, which, although it does not support all of SystemVerilog, does support Verilog 2005 with some SystemVerilog elements, sufficient for solving our tasks. Icarus Verilog is used with GTKWave, a program for working with timing diagrams. We will not need GTKWave for the first ten tasks, but it is worth installing it together with Icarus Verilog for the future.

Installation on Linux

Under Ubuntu and Debain based Linux you can install Icarus Verilog and GTKWave with the command:

sudo apt-get install verilog gtkwave

Note:

If you have an old version of Linux distribution (Ubuntu), then when you install Icarus Verilog you will get an old version that does not support always_comb, always_ff and many other SystemVerilog constructs. How to solve this problem:

Checking iverilog version
```
iverilog -v
```
If the iverilog version is less than 11, go to point 3.

Installation of preliminary packages

sudo apt-get install build-essential bison flex gperf readline-common libncurses5-dev nmon autoconf

Download the latest version of iverilog

To date (8.25.2024) the latest version of Iverilog: 12.0 Go here and download the archive.
Assembly iverilog
- Extract the archive:
```
tar -xzf verilog-12.0.tar.gz
```
- Enter into the verilog folder:
```
cd verilog-12.0
```
- Configure iverilog:
```
./configure --prefix=/usr
```
- Run the make checks
```
make check
```
  As a result, several inscriptions of HELLO, World! Will appear in the terminal
- Install icarus
```
sudo make install
```

Verilator

Additionally, to check the code for some syntactic and stylistic errors, you can install Verilator (version 5.002+).

For Ubuntu 23.04 and above:

sudo apt-get install verilator

For earlier versions of Ubuntu or other distributions, you can install Verilator along with OSS CAD Suite.

If using OSS CAD SUITE, for setting the environment, it is recommended to use export PATH="<extracted_location>/oss-cad-suite/bin:$PATH" instead of source <extracted_location>/oss-cad-suite/environment, because latter requires additional unset VERILATOR_ROOT command.

To perform the check, add the --lint or -l option to the script: ./run_linux_mac.sh --lint

The result will be written to lint.txt

Installation on Windows

The Icarus Verilog version for Windows can be downloaded from this site

Video Instructions for the installation of icarus verilog on Windows

Installation on Apple Mac

Icarus can even be put on Apple Mac, which is unusual for EDA tools (EDA - Electronic Design Automation). This can be done in the console using the Brew:

brew install icarus-verilog

Video Instructions for the installation of icarus verilog on macos

Execution and checking tasks

To check the tasks for Linux and MacOS, you need to open the console in the folder and start the script ./run_linux_mac.sh. It will create a file log.txt with the results of compilation and simulation of all set tasks.

To check the tasks for Windows, you need to open the console in the task folder and run the bat file run_windows.bat. This will also create a file log.txt with the results of the check.

After the test for all tasks will show PASS.

GTKWave alternative

Instead of GTKWave you can use cross-platform waveform viewer Surfer.

It looks much nicer on modern screens (and especially on Wayland), works faster and you can even try it out in your web browser without installing.

Surfer

Recommended literature that will help in solving problems

Harris D.M., Harris S.L., “Digital circuitry and computer architecture: RISC-V”. There is a version for a tablet for a previous edition (based on MIPS architecture), but there are shorter slides for lectures.
Романов А.Ю., Панчул Ю.В. и коллектив авторов. «Цифровой синтез. Практический курс»