Manual
www.nexusrobot.com Robot Kits manual 
  17
 digitalWrite(ledPin, LOW);  // Set a low value to the ledPin 
 } 
}  
 Arduino button 
¾  Interrrupt control 
Description 
Specifies a function to call when an external interrupt occurs. Replaces any previous function that was 
attached to the interrupt. Most Arduino boards have two external interrupts: numbers 0 (on digital pin 2) 
and 1 (on digital pin 3). The Arduino Mega has an additional four: numbers 2 (pin 21), 3 (pin 20), 4 (pin 
19), and 5 (pin 18). 
Sample code 
int pin = 13; 
volatile int state = LOW; 
void setup() 
{ 
 pinMode(pin, OUTPUT); 
 attachInterrupt(0, blink, CHANGE); 
} 
void loop() 
{ 
 digitalWrite(pin, state); 
} 
void blink() 
{ 
 state = !state; 
} 










