u/AddressFuture7888

I'm trying to map out my ti-30x plus keypad matrix, by probing the ground and then the one next to it, then pressing a button as you do, but I cant make a connection to any button.

I'm using an arduino with a wire on the ground and pin 2 since I don't have a multimeter.

yes I'm trash at this, and yes I'm a beginner.

this was the code:

void setup() {
  Serial.begin(9600);
  pinMode(2, INPUT_PULLUP);
}


void loop() {
  if(digitalRead(2) == LOW) {
    Serial.println("CONTACT!");
  }
  delay(50);
}