how to debug the fpga?

[peteasa]

I wonder if anyone has used iverilog to debug the FPGA? That plus gtkwave are a very powerful pair of applications to debug.

It would require a bit of setup with some test scripts but might help debug custom FPGA changes.

[peteasa]

Here is an example of the output from gtkwave during the startup of the iir module

[nano-aaiv]

I haven't! But I'm interested in this topic. What's the advantage of iverilog? Can we use vivado's simulator for this purpose?

[peteasa]

The advantage of iverilog is that it is quick to make changes and re-run the simulation. I have pushed my version of the harness here https://github.com/peteasa/pyrpl_testbench/tree/main/fpga. This does not replace the vivado simulator, its just very quick to run with little overhead.

Also I like to keep the test code separate from the production code. It seems very easy to do that with the iverilog compiler.