FireBeetle ESP32 Tutorial: Blinking the on board LED

DFRobot Apr 26 2018 3369

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
}
 
void loop() {
  digitalWrite(LED_BUILTIN, HIGH);
  delay(2000);
  digitalWrite(LED_BUILTIN, LOW);
  delay(2000);
}

FireBeetle ESP32 Tutorial: Blinking the on board LED

The objective of this post is to explain how to make the DFRobot’s FireBeetle ESP32 board built in LED blink.

Introduction

The code

The code for this tutorial will be very simple, since it will be kind of a “Hello World” program using the hardware. So we will be basically using the Arduino digitalWrite function, which allows us to control if a digital pin is in a HIGH or LOW state.

So, one of the constants defined is the LED_BUILTIN, which has the value of the on board LED for the board we are using. Naturally, this will only work for boards that are configured in the environment, which is the case of the FireBeetle ESP32.

As for the code, we start by declaring the operating mode of our pin in the setup function. to do so, we use the pinMode function, which receives as arguments the number of the pin we want to configure and the mode.

As stated before, we will pass as first argument the constant LED_BUILTIN and as second OUTPUT, which indicates that the pin will operate in output mode. You can read more about the constants for operating modes that can be passed to the function here.

Then, in the main loop function, we will turn the digital pin on and off by calling the previously mentioned digitalWrite function. This function will receive as input the pin number and the value we want to set.

Again, for the pin number we will use the LED_BUILTIN, and as value we will alternate between HIGH and LOW, so we get the desired blinking effect.

You can check the final code bellow. I’m using a delay of 2 seconds (2000 milliseconds), but you can change both of the delays to control how much time the LED is on and off.

Testing the code

To test the code, we need to have the FireBeetle ESP32 board selected on the Tools menu, on the Board entry of the Arduino IDE. Then, we just need to hit the upload button and the code should be compiled and uploaded. You can check in the video bellow the expected result.