LED Light (D13)

The RedBot mainboard has a built-in green LED light that can be controlled by your program. The LED is hardwired to pin D13 on the RedBot mainboard and is located near the center-right of the mainboard.

The LED can be used to provide alerts or feedback (usually in combination with sound from the speaker).

How to Code LED

To use the LED light in your robot app, you will need to:

  1. Declare a global variable to store the LED's pin number

  2. Set the pin mode for the LED

  3. Use the digitalWrite() method to turn the LED on and off

Declare Variable for LED

You'll need to create a global variable to store the pin number of the LED, which is connected to pin D13. Add this code statement before the setup() function:

int LED = 13;

Set Pin Mode for LED

You'll need to set the pin mode for the LED. Add this code statement within the setup() function:

pinMode(LED, OUTPUT);

Turn LED On and Off

The digitalWrite() method can be used to send an "on" or "off" signal to the LED by using a value of either HIGH or LOW:

  • HIGH will turn on the LED

  • LOW will turn off the LED

After turning on the LED, you will typically use the delay() method to add a waiting period (in milliseconds) before turning off the LED.

For example, the following code will turn on the LED for 0.5 seconds and then turn it off:

digitalWrite(LED, HIGH); // turn on
delay(500); // wait 0.5 seconds
digitalWrite(LED, LOW); // turn off

You can code your own sequence of digitalWrite() and delay() statements to make the LED turn on and off in different patterns (e.g., double blink, slow blink, fast blink, etc.)

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