WEEK 8

    ✦ Copy


// Pin Definitions
const int leds[] = {D1, D2, D3, D8, D9};
const int numLeds = 5;
const int btnPin = D10;

int mode = 0; // 0: Off, 1: Steady, 2: Blink, 3: Alternate
bool lastBtnState = HIGH;

void setup() {
  for (int i = 0; i < numLeds; i++) pinMode(leds[i], OUTPUT);
  pinMode(btnPin, INPUT_PULLUP); // Internal pull-up resistor
}

void loop() {
  bool currentBtnState = digitalRead(btnPin);

  // Button press detection 
  if (currentBtnState == LOW && lastBtnState == HIGH) {
    delay(50); // Debounce
    mode = (mode + 1) % 4; // Cycle through 0-3
    setAll(LOW); 
  }
  lastBtnState = currentBtnState;

  // Mode Selector
  switch (mode) {
    case 1: setAll(HIGH); break;           // STEADY ON
    case 2: blink(200); break;             // BLINK
    case 3: alternateEffect(); break;      // ALTERNATE
    default: setAll(LOW); break;           // OFF
  }
}

// --- Helper Functions ---

void setAll(int state) {
  for (int i = 0; i < numLeds; i++) digitalWrite(leds[i], state);
}

void blink(int speed) {
  setAll(HIGH); delay(speed);
  setAll(LOW);  delay(speed);
}

void alternateEffect() {
  for (int i = 0; i < numLeds; i++) {
    digitalWrite(leds[i], (i % 2 == 0)); // Pattern: ON, OFF, ON...
  }
  delay(300);
  for (int i = 0; i < numLeds; i++) {
    digitalWrite(leds[i], (i % 2 != 0)); // Pattern: OFF, ON, OFF...
  }
  delay(300);
}