Help With a DIY button pad

I’m looking for help figuring out some light-up button-pad PCBs I bought. (They have limited documentation but hey, were they cheap!) I’ve got a general knowledge of circuitry and Arduino programming, and I know that this type board board needs a controller to run it. I think I understand how they work, but I’d like to double-check, if anyone has experience in this area.

They each are a 4x4 membrane switch matrix and a 4x4 programmable LED / NeoPixel matrix combined into one board, (link here) and while the two functions share power and ground, the lights are all software controlled. I’d imagine you could use if for either purpose exclusively if you didn’t want buttons and lights together…

This board specifically came from a US manufacturer called LeafCutter, and is an upgraded version of an unavailable SparkFun board that didnt use neopixels, just RGB LEDs in matrix. Sparkfun has some guides explaining how their board works, but this one is different enough to raise questions. Basically, since this PCB is an upgrade, there’s no documentation on the LeafCutter page about what diodes to use, or what other SMD components they used, though they indicate the completed board has diodes, capacitors and LEDs on it.

I’m under the impression that the LEDs are all tied together in sequence as labeled, and they work like a string of NeoPixels 16 or 8 long. I’m less sure about the buttions, since the examples use different components. I guess the diodes can be THT or SMD, but either way one is required? Also, there appear to be SMD capacitors used to debounce inputs, maybe? That’s about where my experience with DIY circuitry ends…

Any help or guidance would be appreciated!

The diodes are thru hole. Nothing fancy. 1N914 should do. Tanners will have them. Cheap.

Looks like there are holes for the caps as well. If you’re new to electronics, stay away from surface mount for a while. You’ll want to know how to do that eventually, but it’s a pain. Start simple.

Read the part of the Sparkfun writeup about scanned keyboards. That’s one piece.

Then you need to find a neopixel tutorial. I’d recommend FastLED - which is a library for Arduino.

You will have to write some software to make all this work. Arduino is simple. Good place to start.

Good luck !