An USB isolator will help reduce ground loops and lessens electromagnetic interference (EMI) in between the pc and the related system. 1x GND 3V3 (P2 with 2 pins two.54mm) connector can be used to electrical power externally the WCH CH569 MCU (it is usually recommended to remove the P4/SHUNT in https://erichs283bsk9.fare-blog.com/profile