Traditionally, interfacing a microcontroller with an n-by-m keypad required n + m of the microcontroller's I/O pins for keypad scanning. Keypad designs that conserve microcontroller pins have been ...

Designers of microcontroller-based products that require a keypad for user data entry can select from dedicating an input line for each key, continuously polling the keypad's x and y lines, or ...

16-button keypads have a clever method of encoding their data into 8 pins. Pins are mapped to four rows and four columns on the keypad. A user reads the keypad by bringing each row up to logic: HIGH, ...

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 ...