The I2CKeyPad library implements the reading of a 4x4 keypad by means of a PCF8574. Smaller keypads, meaning less columns or rows (4x3) can be read with it too. Since 0.3.2 the library allows a 5x3, ...

In this tutorial we are going to interface a 4x4 (16 key) keypad with ARDUINO UNO. We all know keypad is one of the most important input devices used in electronics engineering. Keypad is the easiest ...

TCA6416A - 16-bit port, addresses 0x20 or 0x21, sig level translating. PCA9554A - 8-bit port, addresses 0x70..0x77 (PCA9554 is 0x20..0x27). PCA9535 - 16-bit port, addresses 0x20..0x27 PCA9534 - 8-bit ...

A 4x4 membrane keypad is a compact and a cost-effective input device that is commonly used in a variety of electronics projects. It consists of 16 buttons arranged in a 4x4 grid and is covered with a ...