damianstone / digital-systems-vhdl

Running VHDL Code with GHDL and GTKWave

This guide explains how to compile and simulate VHDL code using GHDL and view the results with GTKWave on a Unix-like system (Linux/macOS). The example code used here is for a simple 4-to-1 multiplexer, but the process is similar for other VHDL code.

Prerequisites

• GHDL (VHDL compiler and simulator)
• GTKWave (VCD waveform viewer)

Instructions

1. Install GHDL and GTKWave:

   Ensure you have GHDL and GTKWave installed on your system. You can install them using package managers such as Homebrew (on macOS), apt-get (on Ubuntu), or dnf (on Fedora).

   # Install GHDL
   brew install ghdl  # macOS
   sudo apt-get install ghdl  # Ubuntu
   sudo dnf install ghdl  # Fedora
   
   # Install GTKWave
   brew install gtkwave  # macOS
   sudo apt-get install gtkwave  # Ubuntu
   sudo dnf install gtkwave  # Fedora
   
   

Run code

Compile VHDL code

ghdl -a your_file.vhdl

Elaborate the desing

ghdl -e entity_name

Run the simulator

ghdl -r entity_name --vcd=waveform.vcd

View the Results with GTKWave

gtkwave waveform.vcd