A powerful midi synth based on the stm32f103cb IMPORTANT:This project uses the stm32f103cb NOT the stm32f103c8, the code requires 110k of flash. The coocox website is down so you need to get it from somewhere else:(that "somewhere else" https://www.softpedia.com/get/Programming/Coding-languages-Compilers/CooCox-CoIDE.shtml)
Precompiled bin file in usb_synth/MIDI_USB_Synth/Debug/bin/
Video of it:https://youtu.be/Z8oxVrtKEWA
Schematic:https://easyeda.com/elpro/stm32f103cb-synth
More info on:https://mitxela.com/forum/topic/stm32f103cb-synth-a-powerful-synth