Versatile remote IO design

Author	Message
Mixtel90 Guru Joined: 05/10/2019 Location: United Kingdom Posts: 8963	Posted: 11:04am 08 Jul 2025       I tried it a while ago. Just an experiment to make a I2C game controller. Actual data transfer is very reasonable, but it will depend on your protocol more than anything else. I wouldn't recommend doing remote IO any faster than 100kHz due to cable length issues as it's really designed for on-board communication. The other problem is that I2C isn't buffered so you have to work round that. I used about 600mm of telephone wire and 100kHz. The controller was handled by the master asking it for registers or register sets, so you might only ask for the buttons as a byte (very fast) or both of the X and Y positions of the analogue joystick - slower obviously. The controller used a RP2040-Zero.