The keypad library is available from https://github.com/Chris--A/Keypad

Extract its contents, and put a folder named "Keypad" in your libraries folder. The contents of the Keypad-master.zip must be placed in that folder, do not extract it all into the libraries folder without creating the "Keypad" folder. If the Arduino program is open, close it and start it up again.

Wiring the System Together

First insert the Arduino Nano into the breadboard, making sure that the two rows of pins are on either side of the furrow in the middle.







TIP: Position the USB mini port so that it faces outward from the breadboard. This way it will not clutter up your wiring with a USB cable running through it.

The 4x3 keypad used in this tutorial has 7 female pin sockets, all of which need to be wired to the Arduino.

The keypad module uses 1, 2, 3, 4, for ROW0, ROW1, ROW2, ROW3, and pins 5, 6, 7 for COL0, COL1, COL2.

Wire it up as follows





Keypad > Arduino

> ROW0 > ROW1 > ROW2 > ROW3





Pins: