4X4 KEYPAD is used as input in a project. It has 16 keys in total, which means the same input values. The 4 x 4 Matrix Keypad Module is a non-encoded matrix keypad consisting of 16 keys in parallel. The keys of each row and column are connected through the pins outside – pin R1-R4 as labeled beside control the rows, when L1-L4, the columns. A 4×4 matrix keypad consisting of microswitch buttons. The module has four holes 3mm (M3) holes for mounting. The pin designations on each PCB are shown on each PCB. Four pins are thus used as an ‘x’ coordinate and the other 4 as a ‘y’ coordinate. The module is already equipped with a soldered pin-headers.