I haven't yet purchased a multimeter but there are a couple I'm looking at trying to decide which one to purchase. To simplify things a bit, I'll narrow the scope and provide some additional details.
What I want to do is build a controller for a popular Taiko drum game that's been officially released on several game consoles as well as a PC clone. I was pointed to this project which uses an Arduino to turn the piezos into a USB controller: GitHub - LuiCat/ArduinoTaikoController: Sketch for Arduino based taiko game controller circuit for PC and Nintendo Switch . However, it's missing a couple of things. In the original arcade version of the game, you can tap the drum and it registers a normal hit but if you hit the drum controller harder it registers a harder hit that is the same as hitting both sides of the drum at the same time. I would like to see if I can figure out how to modify that project to do the same thing.
Also, I wanted to use the controller with a Nintendo Wii console, which I could do if I can figure out how to get the piezos to trigger buttons on a Wii Classic Controller PCB. The Classic Controller has inputs from the main Wii controller with two 3.2v pins, SDA, SCL, and ground according to the schematics that I found. Triggering the buttons requires grounding them, I believe, which is what happens when you press one of the buttons the face of the controller.