There was a typo in my message
OSCBot can receive "random"
MIDI data. It can't connect to a "COMx" device in Windows, but just to a MIDI device. But if your µC is recognized by Windows as an USB Midi device this will be fine.
Of course you need to adhere to the Midi spec and send only messages that start with a Byte with bit 7 set and the bytes with bit seven cleared (SysEx: 0xF0, ..... 0xF7)
-Michael