code: async function hardreset(devicename){
      // initiate lowlevel connection
      if (!_virtualTerminal.isConnected()){
          await _virtualTerminal.connect(devicename, 115200);
      }
  
      // pull down RST pin using the reset circuit
      await _virtualTerminal.flowcontrol({
          dtr: false,
          rts: true
      });
  
      // 100ms delay
      await _async.sleep(100);
  
      // restore previous state after 100ms
      await _virtualTerminal.flowcontrol({
          dtr: false,
          rts: false
      });
  }
docs: reset NodeMCU devkit - compatible with devices using rts/dtr reset/programming circuit @see https://github.com/nodemcu/nodemcu-devkit-v1.0/blob/master/NODEMCU_DEVKIT_V1.0.PDF Page #3 Reset => DTR=1, RTS=0