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

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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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Hey,

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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