Description CH55x is the 8bit enhanced C51 MCU USB function board, design from WCH company. CH551 is the cheapest entry version of CH55x series. Features USB Stick board size On board power led On board GPIO testing led P3.0 No need programmer, not even USB-TTL tool! To enter into programming mode, use a tweezer, short connect the two pins in the middle of the board, where marked as “DL” All lead out pins. Price for one board only. All documentation please find at CH55X wiki page, or customer github. WCH CH55x Series: CH551 CH552 and CH554 CH559 USB CDC Touch Relay Control Board CH554
