code: def _writeData(self, command, device, params=()):
          
          sequence = []
  
          if self._compact:
              sequence.append(command | 0x80)
          else:
              sequence.append(self._BAUD_DETECT)
              sequence.append(device)
              sequence.append(command)
  
          for param in params:
              sequence.append(param)
  
          if self._crc:
              sequence.append(crc7(sequence))
  
          self._serial.write(bytearray(sequence))
          self._log and self._log.debug("Wrote byte sequence: %s",
                                        [hex(num) for num in sequence])
docs: Write the data to the device.
  
          :Parameters:
            command : `int`
              The command to write to the device.
            device : `int`
              The device is the integer number of the hardware devices ID and
              is only used with the Pololu Protocol.
            params : `tuple`
              Sequence of bytes to write.
  
          :Exceptions:
            * `SerialTimeoutException`
              If the low level serial package times out.
            * `SerialException`
              IO error when the port is not open.