The IIC 2004 LCD display module is a 4 line 20 character LCD module not only set the contrast control knob selector switch also has a backlight and IIC communication interface. For beginners, not for the cumbersome and complex LCD driver circuit connection and a headache, the real significance of this LCD module will simplify the circuit, this module directly into the Sensor Shield V5.0 sensor expansion board IIC device interface can, GM 4P sensor connection cable, programmed through the controller, you can easily identify the slogan, sensor data records.