ESP32 - BLINK LED

void setup() {                  // the setup function runs once when you press reset or power the board
    pinMode(15, OUTPUT);        // initialize digital pin GIOP18 as an output.
}
void loop() {                   // the loop function runs over and over again forever
    digitalWrite(15, HIGH);     // turn the LED on (HIGH is the voltage level)
    delay(1000);                // wait for 1000 milliseconds
    digitalWrite(15, LOW);      // turn the LED off by making the voltage LOW                                                
    delay(1000);                // wait for 1000 milliseconds
}                

Quick Steps

• power up your board
• Open Arduino IDE
• Select the right board
• Select the right port
• Copy the above code and open with Arduino IDE
• Click Upload button on Arduino IDE to upload code to ESP32

• Press and keep pressing the button several seconds
• See the changes you made

Code Explanation

• configure an ESP32's pin to digital output mode by using pinMode() function.
• program the pin to GND to turn off led by using digitalWrite(pinNumber,LOW)
• program the pin to VCC to turn on led by using digitalWrite(pinNumber,HIGH)

Read the line-by-line explanation in comment lines of source code!