I'm quite inexperienced with electronics in general, so there could be inaccuracies in this.
I have taken the circuit board from an old sky (cable/satellite) box that had some buttons on it. It has a 8 pin ribbon cable attached to it and 9 buttons. The only other components on the board are 3 diodes.
It's a fairly simple layout so I was able to use my multimeter and work out this diagram.
Now, I was planning to connect this to a micro controller, a pi pico to be specific. However I can't work out how I can read which button has been pressed. (aside from IO7 & IO8)
I was thinking that I could supply 3.3v on each of the diode inputs, but if I do that then multiple buttons can trigger the same IO output.
My next thought was that I could supply each of the input diodes one at a time, scanning the outputs before moving to the next input. I imagine I can do this on the controller, but wasn't sure if that's the best way to go about this?
Is this a common type of button setup? I'm happy to do a bit more googling if someone can give me the right keywords.