The PT-30 that I got is broken and I have no starting point. When I turn it on, the display starts briefly showing something and then dies quickly. There's no short, so it might be the CPU that's busted sadly.
Maybe I should try to recreate what I loved most about this, the chord buttons with the variation buttons.
I mean I could also try to combine these 2, just need to figure out if I can add I2C to any left over pins, if I have any :D
Managed to write a very rudimentary I2C peripheral code for the step sequencer that should respond with button states and allow LED states to be sent. I can find it on my LoKiPAD via I2C, by using "leftover" pins that I can use by just defining them before calling the Wire.begin() function.
Wire.setSDA(16);
Wire.setSCL(13);
Wire.begin();
Dave
Carsten
Bornach
AxWax