An USB isolator aids do away with ground loops and lowers electromagnetic interference (EMI) between the computer as well as the connected product. 1x GND 3V3 (P2 with two pins 2.54mm) connector may be used to ability externally the WCH CH569 MCU (it is suggested to remove the P4/SHUNT in https://geraldj950tkc6.hazeronwiki.com/user