Primeiro Programa

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/*
  BlinkRGB

  Demonstrates usage of onboard RGB LED on some ESP dev boards.

  Calling digitalWrite(RGB_BUILTIN, HIGH) will use hidden RGB driver.

  RGBLedWrite demonstrates control of each channel:
  void neopixelWrite(uint8_t pin, uint8_t red_val, uint8_t green_val, uint8_t blue_val)

  WARNING: After using digitalWrite to drive RGB LED it will be impossible to drive the same pin
    with normal HIGH/LOW level
*/
//#define RGB_BRIGHTNESS 64 // Change white brightness (max 255)

// the setup function runs once when you press reset or power the board
void setup() {
  // No need to initialize the RGB LED
}

// the loop function runs over and over again forever
void loop() {
  digitalWrite(RGB_BUILTIN, HIGH);  // Turn the RGB LED white
  delay(1000);
  digitalWrite(RGB_BUILTIN, LOW);  // Turn the RGB LED off
  delay(1000);
}

Referências