SOURCE CODE:
//www.elegoo.com
#define LED 13 //Define 13 pin for LED bool state = LOW; //The initial state of the function is defined as a low level char getstr; //Defines a function that receives the Bluetooth character
void setup() { pinMode(LED, OUTPUT); Serial.begin(9600); }
//Control LED sub function void stateChange() { state = !state; digitalWrite(LED, state); }
void loop() { //The Bluetooth serial port to receive the data in the function getstr = Serial.read(); if(getstr == 'a'){ stateChange(); } }