Good day, I actually like your project and I feel I've capabilities to assist you. Your software has become submitted.1x GND 3V3 (P2 with two pins 2.54mm) connector may be used to electric power externally the WCH CH569 MCU (it is usually recommended to eliminate the P4/SHUNT in that situation It's not necessarily mandatory since the 3V3 LDO IC1 is