I've spent quite some time (as you might know if you've seen other blog posts) working with the TI Stellaris Launchpad - now known as the Tiva-C Launchpad for reasons I never did understand. I thought I've had a look at the datasheet and low and behold - 5V tolerant I/O.
So, a plan is forming:
- Create a base board for the Launchpad, like I did for the in-car dashboard
- Drive the L298 inputs from a open-drain GPIO with a pull-up.
- Read the quadrature encoder inputs directly (the GPIO will deal with it OK).
- It can interrupt on any GPIO pin, so no problem there.
- It's fast - A 67MHz Cortex-M4F won't have any problems running four seperate PID loops.
- The Pi can connect via USB for both power, control (Serial) and flashing/debug.
- I know I can get the programmer to work.
- I know I can program it in Rust...