// 74HC4067 multiplexer demonstration for 16 buttons and 16 relays

// Control pins for 74HC4067 for buttons
#define btnMux_S0 7   // S0 pin (A)
#define btnMux_S1 6   // S1 pin (B)
#define btnMux_S2 5   // S2 pin (C)
#define btnMux_S3 4   // S3 pin (D)

// Control pins for 74HC4067 for relays
#define relayMux_S0 3   // S0 pin (A)
#define relayMux_S1 2   // S1 pin (B)
#define relayMux_S2 1   // S2 pin (C)
#define relayMux_S3 0   // S3 pin (D)

#define analogPin A0  // Analog pin connected to 74HC4067 Z pin for reading button states

byte btnControlPins[] = {
  B00000000, B10000000, B01000000, B11000000,
  B00100000, B10100000, B01100000, B11100000,
  B00010000, B10010000, B01010000, B11010000,
  B00110000, B10110000, B01110000, B11110000
};

byte relayControlPins[] = {
  B00000000, B10000000, B01000000, B11000000,
  B00100000, B10100000, B01100000, B11100000,
  B00010000, B10010000, B01010000, B11010000,
  B00110000, B10110000, B01110000, B11110000
};

byte btnValues[16] = {0};  // Holds button states read from 74HC4067
byte relayStates[16] = {0}; // Holds relay on/off states

void setup()
{
  Serial.begin(9600);

  // Set control pins as outputs
  pinMode(btnMux_S0, OUTPUT);
  pinMode(btnMux_S1, OUTPUT);
  pinMode(btnMux_S2, OUTPUT);
  pinMode(btnMux_S3, OUTPUT);

  pinMode(relayMux_S0, OUTPUT);
  pinMode(relayMux_S1, OUTPUT);
  pinMode(relayMux_S2, OUTPUT);
  pinMode(relayMux_S3, OUTPUT);

  // Initialize serial monitor and delay
  delay(1000);
}

void loop()
{
  // Read button states
  for (int i = 0; i < 16; i++) {
    setBtnPin(i); // Set pin on 74HC4067 for reading button state
    btnValues[i] = digitalRead(analogPin); // Read button state and store in array
  }

  // Display button states
  displayButtonStates();

  // Control relays based on button states (example)
  controlRelays();
}

void setBtnPin(int pin)
{
  digitalWrite(btnMux_S0, bitRead(btnControlPins[pin], 0));
  digitalWrite(btnMux_S1, bitRead(btnControlPins[pin], 1));
  digitalWrite(btnMux_S2, bitRead(btnControlPins[pin], 2));
  digitalWrite(btnMux_S3, bitRead(btnControlPins[pin], 3));
}

void setRelayPin(int pin)
{
  digitalWrite(relayMux_S0, bitRead(relayControlPins[pin], 0));
  digitalWrite(relayMux_S1, bitRead(relayControlPins[pin], 1));
  digitalWrite(relayMux_S2, bitRead(relayControlPins[pin], 2));
  digitalWrite(relayMux_S3, bitRead(relayControlPins[pin], 3));
}

void displayButtonStates()
{
  Serial.println("Button States:");
  Serial.println("=================");
  for (int i = 0; i < 16; i++) {
    Serial.print("Button ");
    Serial.print(i);
    Serial.print(": ");
    Serial.println(btnValues[i]);
  }
  Serial.println("=================");
  Serial.println();
}

void controlRelays()
{
  // Example: Control relays based on button states
  for (int i = 0; i < 16; i++) {
    if (btnValues[i] == HIGH) {
      // Turn on corresponding relay
      setRelayPin(i);
      digitalWrite(relayMux_S1, HIGH);
      relayStates[i] = 1;
    } else {
      // Turn off corresponding relay
      setRelayPin(i);
      digitalWrite(relayMux_S1, LOW);
      relayStates[i] = 0;
    }
    delay(100); // Delay for stability (adjust as necessary)
  }
}