intledPin = 3;
void setup()
{
Serial.begin(9600);
Serial.println(“Serial connection started, waiting for instructions…n0 = Offn1 = 25%n2 =50%n3 = 75%n4 = 100%”);
}

void loop ()
{
if (Serial.available()) {
char ser = Serial.read(); //read serial as a character

//NOTE because the serial is read as “char” and not “int”, the read value must be compared to character numbers
//hence the quotes around the numbers in the case statement

switch (ser)
{
case ‘0’:
analogWrite(ledPin, 0);
break;

case ‘1’:
analogWrite(ledPin, 64);
break;

case ‘2’:
analogWrite(ledPin, 128);
break;

case ‘3’:
analogWrite(ledPin, 192);
break;

case ‘4’:
analogWrite(ledPin, 255);
break;
default:
Serial.println(“Invalid entry”);

}
}
}