When I was first testing my designs inside Caravel, I was quite confused about all the GPIO options.

• Each pin has a range of options that can be configured by firmware running on the RISCV processor.
• Each pin can be driven from the processor or your custom design.
• The outputs have separate output enable lines for bi-directional signalling.

I put together an experiment where I tried the most important options and checked the results in a simulation. You can watch the video here:

• Supporting documentation
• The github repository is here: https://github.com/mattvenn/caravel_gpio

• caravel