So, some changes:
- moving to the STM32H723 board with a display. The project was rebuilt in CubeIde
- added a display to display some information
- added a relay. Now there is no need to pull out/plug the plug into the outlet
- an encoder has been added. You can adjust some parameters and turn off the piano
- added saving of parameters in non-volatile memory
- added standby mode. When you turn on the piano, it goes to sleep. It is activated by a button on the controller board. In case of inactivity, it turns off after 10 minutes. It can also be disabled using an encoder. Now there is no need to disconnect the USB cable
- an error has been identified and fixed due to which every 8th key sometimes played a slow speed
- keyboard scanning has been slightly accelerated. Now the keyboard scanning speed is more than 300 kHz (~310)
- the light indicates that the speed is exceeded
https://youtu.be/30M5jO6VT-U
https://github.com/ScherbakovAl/midi_keyboard_h723