//**** LED Blinking *******
const int ledPin = 25; 
void setup() {
 // setup pin 25 as a digital output pin
 pinMode (ledPin, OUTPUT);
} 
void loop() {
 digitalWrite (ledPin, HIGH); // turn on the LED
 delay(500); // wait for half a second or 500 milliseconds
 digitalWrite (ledPin, LOW); // turn off the LED
 delay(500); // wait for half a second or 500 milliseconds
}