Interrupts

This library allows you to trigger a process interrupt function or enable/disable an interrupt function when the input to a pin changes value.

attachInterrupt

Description
Specifies a function to execute (call) when an external interrupt occurs (signal on external pin).
Syntax
attachInterrupt(pin, void(*)(void) func, mode)
Parameters
pin: The number of the pin being used for the interrupt(11, 12)
func: The function to call when the interrupt occurs
mode:
   LOW (to trigger the interrupt whenever the pin is low)
   CHANGE (to trigger the interrupt whenever the pin changes value)
   FALLING (for when the pin goes from high to low)
   RISING (to trigger when the pin goes from low to high)
Returns
None

detachInterrupt

Description
Turns off the interrupt specified in attachInterrupt.
Syntax
detatachInterrupt(pin)
Parameters
pin: The number of the pin being used for the interrupt (11, 12)
Returns
None

interrupts

Description
Re-enables the interrupt disabled in noInterrupts.
Syntax
interrupts()
Parameters
None
Returns
None

noInterrupts

Description
Disables an interrupt process. Use this when you need to protect the timing of a specific process; this can even be used to disable an important task ran in the background.
Syntax
noInterrupts()
Parameters
None
Returns
None

Sample Program

LED lights up when the button on GR-ADZUKI is pushed.


#include <Arduino.h>
 
void blink()
{
  state = !state;
}
 
int pin = PIN_LED0;
volatile int state = LOW;
 
void setup()
{
  pinMode(pin, OUTPUT);
  attachInterrupt(0, blink, CHANGE);
}
 
void loop()
{
  digitalWrite(pin, state);
}