Operation of MM74C922N 4x4 matrix keypad

Hi I have been studying the datasheet of the MM74C922N [https://www.soemtron.org/downloads/disposals/74c922.pdf] , a 4x4 matrix keypad, but I cannot seem to understand how it works under the 'Theory of Operation'. I know it outputs a 4bit binary code depending on the key pressed but other than that, I don't know how it actually works internally. Can anyone explain it in simpler terms? Thanks

by LilBoy23
November 14, 2021

I've been playing with a 4x4 keypad and reading it with an Arduino UNO or NANO. I got it working nicely (and simply) with the Arduino "keypad" library so if you wish I can give you information on that.
I took a look at the reference you gave and I can only describe it as masochistic when controllers such as the Arduino line (and others) are available.

by Foxx
November 14, 2021

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