// 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));

}