The LCD Keypad Shield is arduino compactible boards,to provide a user-friendly interface that allows users to display what they want to and make selections etc. it consists of a 1602 white character blue backlight LCD. The keypad consists of 5 keys — select, up, right, down and left. To save the digital IO pins, the keypad interface uses only one ADC channel(AD0). The key value is read through a 5 stage voltage divider.