// CREATED AND DESIGNED BY MARVIN A. QUIZZAGAN
// DATED: FEBRUARY 21, 2026
// Arduino Nano - Switching Between RF Module and Head Press Buttons
//
// External Pull-Up Resistors:
// D9 → A0
// D8 → A1
//
// NEW FUNCTION: FEBRUARY 23, 2026
// D7 (INPUT_PULLUP) → A2 (INVERTED OUTPUT)
const byte IN1 = 9; // Input 1 (External pull-up)
const byte OUT1 = A0; // Output 1
const byte IN2 = 8; // Input 2 (External pull-up)
const byte OUT2 = A1; // Output 2
const byte IN3 = 7; // NEW Input 3 (Internal pull-up)
const byte OUT3 = A2; // NEW Output 3 (Inverted)
void setup() {
pinMode(IN1, INPUT); // External pull-up
pinMode(IN2, INPUT); // External pull-up
pinMode(IN3, INPUT_PULLUP); // Internal pull-up enabled
pinMode(OUT1, OUTPUT);
pinMode(OUT2, OUTPUT);
pinMode(OUT3, OUTPUT);
}
void loop() {
// Direct mirror
digitalWrite(OUT1, digitalRead(IN1));
digitalWrite(OUT2, digitalRead(IN2));
// Inverted logic for D7 → A2
digitalWrite(OUT3, !digitalRead(IN3));
}