Today I finally sat down and wrote the Python part of the code for walking. Just the basic creep gait for now. I works, but there seems to be a problem with the I²C communication -- as I mentioned previously already, I'm getting OSError sometimes when sending the coordinates to the controller. It turns out that sometimes when that happens, the slave ends up stuck in a state where it won't listen to commands anymore, and has to be restarted.

I looked at the signals with a scope, and I'm pretty sure this is not due to noise on the line or inadequate pull-up resistors. I tried halving the resistors just to make sure, but of course no improvement. I suspect it's a race condition in the software I2C implementation on the ESP8266. Hopefully that will be fixed before the conference.

In the worst case, I will put all the gait code back on the Arduino and just use ESP8266 for remote control, but it would be so much better if you could program it with Python directly.