This is an I2C or Serial user interface comprising a 16x2 LCD COG lcd display and a 25 way keypad interface. There is a choice between serial and I2C interfaces.


  • I2C display 16x1 AND 16x2, mode selectable
  • User selectable I2C address (BV4542)
  • Software adjustable contrast
  • Software variable back light, variable brightness
  • 79 key buffer
  • 25 way keypad interface
  • Interrupt pins
  • Wide voltage 3.3V to 5V
  • 5V: 10mA BL on, 1.5mA BL off, 280uA sleep * see datasheet
  • 3V3: 4.71mA BL on, 1.3mA BL off, 170uA sleep * see datasheet
  • Only 2 wires for full I/O control
  • Wake from sleep by keypad, i2c or serial


The software resource has Arduion, RPi and ESP8266 running micropython examples. These are by no means complete and are provided as examples only.