i finally figured out the i²c bus/mcp23017 (i asked a couple of questions on this forum, but i didn't know you had to write a binary number on the bus ).
i managed to control a stepper motor using i²c, but only with the a0-7 ports. i did some research, but i still can't figure out how to access the b0-7 ports. i use this command to control the a-ports:
bus = smbus.SMBus(1)
0x20 is the adress, and 0x00 makes it work with the a-ports. i read online 0x01 should work with the b ports, but that doesn't seem to work. does anyone know what i am doing wrong?
thanks in advance,