4x4 Matrix Keypad (ADA3844)

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Punch in your secret key (or Jenny’s number) into this numeric matrix keypad. This keypad has 16 buttons, arranged in a telephone-line 4x4 grid. The keys are connected … read more

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does any one have a pin out or data sheet for this 4X4 keypad, sku ada3844

My question is when hooking up to the RPi (say), how does one interface the keypad to say the RPi. I know that you can connect a DTMF encoder (tone sounds according to button pressed) encoder such that when you press a particular key, a particular set of two tones are generated.
But what about interfacing with the RPi. Anything to whet the appetite.

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I found a data sheet for a similar 4x4 matrix, that from what I can tell works in the same way. It seems to use a single byte(8 bits) that is divided into two nibbles(4-bits) that relate to the row and column so when the first button is pressed the byte will be 0001 0001. Though there seems to be a few libraries avaliable so you dont need to worry too much about that.

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