Circuit Lake

People still use 16-key keypad as input device for any embedded project. I could be used as code input device for opening a door or as a general input to any project that requiring the input like alarm circuits, games, puzzles, DTMF generators.

This project will show you how to interface a 16-key keypad to your AVR microcontroller. You will learn how to read the key when a key is pressed and how to take the data and massage to AVR. This project use 74HC922 16-key decoder IC as a pin-saving mechanism © Nevdull

Interfacing 16 Keypad
Project and Documentation
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