A keypad is one of the most commonly used input devices in microprocessor applications. In a standard keypad wired as an X-Y switch matrix, normally-open switches connect a row to a column when ...

The Keypad library is designed for driving matrix style keypads (matrix decoder) when using the Arduino platform. It uses the standard method of selecting a column and scanning all the rows to see ...

These Keypad Matrix use I2C to communicate, 2 pins are required to interface. The Keypad Matrix has an interrupt pin to provide fast detection of changes. This example shows the working of polling.