0712_Blink 예제(성공)

#define LED_BUILTIN D4

/*

 ESP8266 Blink by Simon Peter

 Blink the blue LED on the ESP-01 module

 This example code is in the public domain

 

 The blue LED on the ESP-01 module is connected to GPIO1 

 (which is also the TXD pin; so we cannot use Serial.print() at the same time)

 

 Note that this sketch uses LED_BUILTIN to find the pin with the internal LED

*/

void setup() {

  pinMode(LED_BUILTIN, OUTPUT);     // Initialize the LED_BUILTIN pin as an output

}

// the loop function runs over and over again forever

void loop() {

  digitalWrite(LED_BUILTIN, LOW);   // Turn the LED on (Note that LOW is the voltage level

                                    // but actually the LED is on; this is because 

                                    // it is acive low on the ESP-01)

  delay(1000);                      // Wait for a second

  digitalWrite(LED_BUILTIN, HIGH);  // Turn the LED off by making the voltage HIGH

  delay(2000);                      // Wait for two seconds (to demonstrate the active low LED)

}