// 定義 LED 接腳
#define LED1 13
#define LED2 12
#define LED3 14

// 定義 PWM 設定
const int freq = 5000;
const int ledChannel1 = 0;
const int ledChannel2 = 1;
const int ledChannel3 = 2;
const int resolution = 8;

void setup() {
  // 設定 LED 接腳為輸出模式
  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);

  ledcSetup(ledChannel1, freq, resolution);
  ledcSetup(ledChannel2, freq, resolution);
  ledcSetup(ledChannel3, freq, resolution);

  ledcAttachPin(LED1, ledChannel1);
  ledcAttachPin(LED2, ledChannel2);
  ledcAttachPin(LED3, ledChannel3);
}

void loop() {
  //逐一呼吸燈亮起並熄滅
  for (int i = 0; i < 3; i++) {
    //依序點亮第 i 顆 LED
    ledcWrite(ledChannel1, map(i, 0, 2, 0, 255));
    delay(90);
    ledcWrite(ledChannel2, map(i, 0, 2, 0, 255));
    delay(90);
    ledcWrite(ledChannel3, map(i, 0, 2, 0, 255));
    delay(90);

    //依序熄滅第 i 顆 LED
    ledcWrite(ledChannel1, map(i, 0, 2, 255, 0));
    delay(90);
    ledcWrite(ledChannel2, map(i, 0, 2, 255, 0));
    delay(90);
    ledcWrite(ledChannel3, map(i, 0, 2, 255, 0));
    delay(90);
  }
}