An I2C connector board is pre-soldered to the back of the display PCB. Operation is based on the I2C I/O expander IC PCF8574AT. Ready-made libraries, e.g. for Arduino and Raspberry Pi, are available. The bus address can be changed by soldering jumpers. This allows multiple displays or other devices to be connected to the same bus. There is a jumper for the backlight. A trimmer for contrast adjustment. Supply voltage 5VDC.

• display: 6,6-cm (2.6")
• display dimensions with module: 80 x 36 x 18 mm
• four-wire connection: GND, VCC, SDA, SCL (pin header)
• default I2C bus address: 0x27
• also works with 3,3V bus voltages (Raspberry Pi, micro:bit, ARM)