// PWM Fan Control using ESP32 DevKit-C V4

const int fanPin = 5;            // GPIO5 used for PWM output
const int pwmFreq = 25000;       // 25kHz PWM frequency (quiet fan)
const int pwmChannel = 0;        // Use PWM channel 0
const int pwmResolution = 8;     // 8-bit resolution (0-255)

void setup() {
  Serial.begin(115200);
  
  // Setup PWM functionality
  ledcSetup(pwmChannel, pwmFreq, pwmResolution);
  ledcAttachPin(fanPin, pwmChannel);

  Serial.println("PWM Fan Control Started");
}

void loop() {
  // Gradually increase fan speed
  for (int duty = 0; duty <= 255; duty += 5) {
    ledcWrite(pwmChannel, duty);
    Serial.print("Fan Speed (PWM Duty): ");
    Serial.println(duty);
    delay(100);
  }

  // Gradually decrease fan speed
  for (int duty = 255; duty >= 0; duty -= 5) {
    ledcWrite(pwmChannel, duty);
    Serial.print("Fan Speed (PWM Duty): ");
    Serial.println(duty);
    delay(100);
  }
}