Hi friends, I have some doubts about Caravel GPIOs, I hope you could help me with these: 1. The GPIOs described here in the Skywater readthedocs are used in the Caravel and specifically which version of GPIO: gpio or gpiov2? 2. Could I have the GPIOs pins naked (I mean could I have those pins available without the current circuitry?) 3. In this picture, what is the difference between pad_a_esd_0_h and pad_a_esd_1_h because I don't see any difference for both in the schematic.

1. gpiov2 since gpio is not available for openmpw 2. Caravan has 11 naked pins. They do not have ESD. Other pins have ESD circuitry, but the output drivers can be disabled. afaik the shuttles (not openmpw) are allowed to change the circuitry of every pad. 3. Its just two different esd resistor protected paths.

2. Do you know where are the instructions to disable them? 3. Do you know where are documented those differences or do you know which are they? Thanks a lot Arman.

2. In top level connect oeb signal (oe_n in picture) to one using 1.8V tie cell (do not just connect it to vccd1) 3. The layout file in PDK probably is the best source of information. Again they should be pretty much the same, it is just two separate nets. I tried connecting them to form ~75 ohm resistance in my tapeout design. And in my design they are connected to more resistance and to input buffer.

Thanks a lot @Arman Avetisyan