(partial circuit diagram of the lcd shield) The shield consists of a 1602 white character blue backlight LCD, and a keypad consists of 5 keys (select, up, down, right, and left). To save the digital I ...

The entire design of the keypad is based on the LK204-25-WB-V manual, and may be applied to other models with slight alterations, such as the LK204-25PC I.E. if you have a model that supplies 12v ...