setPortParameters method
Sets the port parameters to the requested values.
_port.setPortParameters(115200, UsbPort.DATABITS_8, UsbPort.STOPBITS_1, UsbPort.PARITY_NONE);
Implementation
Future<void> setPortParameters(
    int baudRate, int dataBits, int stopBits, int parity) async {
  _baudRate = baudRate;
  _dataBits = dataBits;
  _stopBits = stopBits;
  _parity = parity;
  return await _channel.invokeMethod("setPortParameters", {
    "baudRate": baudRate,
    "dataBits": dataBits,
    "stopBits": stopBits,
    "parity": parity
  });
}