This is just some STM32F4DISCOVERY demo application using Rust. It has a simple serial command-interface for controlling (via GPIO) what the LED ring does: cycle clock-wise, counter clock-wise, or follow the accelerometer. The accelerometer is accessed via SPI.
The project also shows how to do unit testing and how to use GitLab CI.
The serial interface is configured on USART 2 and can be accessed using, for example, an USB-to-serial cable connected to a ground pin, and RX to PA2 and TX to PA3.
The interface will output the following lines:
initafter initialization has finished
buttonwhen the user button has been pressed
levelwhen the board is being held in a perfect level position (when in acceleration mode)
The following lines can be given as commands:
onto turn all the leds on (and disable accelerometer/cycle mode)
offto turn all the leds off (and disable accelerometer/cycle mode)
accelto switch to accelerometer mode
cycleto switch to cycle mode
stopto freeze the LEDs in the current position