Hello, I really like your challenge and I believe I've abilities that may help you. Your application has actually been submitted. 1x GND 3V3 (P2 with two pins two.54mm) connector can be used to electricity externally the WCH CH569 MCU (it is recommended to eliminate the P4/SHUNT in that case https://grahamc627kct2.wikicorrespondence.com/user