Hacking Question ATMEGA32U2 Based Switch RCM Jig

[The_Next_Guy]

I remember seeing a topic about using an Arduino to upload a payload but the issue was that the atmega328p doesn't have native USB. The atmega32u does, however. I think a combo atmega32u2 and maybe SPI flash/EEPROM could definitely make this work. Is there any info you guys could provide to the protocol for RCM? The STM32F103 is also a good candidate.