Interrupts

Functions
void	interrupts (void)
void	noInterrupts (void)
void	attachInterrupt (uint32_t pin, void(*userFunc)(void), int mode)
void	detachInterrupt (uint32_t pin)
void	yield (void)

Detailed Description

Function Documentation

interrupts()

void interrupts

(

void

)

Description

Re-enables interrupts (after they’ve been disabled by noInterrupts()

Syntax

interrupts();

Returns

void

Example

void setup() {
}

void loop() {
  noInterrupts();
  // critical, time-sensitive code here
  interrupts();
  // other code here
}

noInterrupts()

void noInterrupts

(

void

)

Description

Disables interrupts (you can re-enable them with interrupts())

Syntax

noInterrupts();

Returns

void

Example

void setup() {
}

void loop() {
  noInterrupts();
  // critical, time-sensitive code here
  interrupts();
  // other code here
}

attachInterrupt()

void attachInterrupt	(	uint32_t	pin,
		void(*)(void)	userFunc,
		int	mode
	)

Description

Digital Pins With Interrupts

Syntax

attachInterrupt(pin, ISR, mode);

See also

https://www.arduino.cc/reference/en/language/functions/external-interrupts/attachinterrupt/

Parameters

pin	the number of the interrupt
ISR	the ISR to call when the interrupt occurs; this function must take no parameters and return nothing. This function is sometimes referred to as an interrupt service routine
mode	defines when the interrupt should be triggered(LOW,CHANGE,RISING,FALLING)

Returns

void

Example

uint8_t ledPin = 36;
uint8_t interruptPin = 13;
volatile byte state = LOW;
long startTime = 0;

void blink()
{
    state = !state;
}

void setup()
{
    pinMode(ledPin, OUTPUT);
    pinMode(interruptPin, INPUT_PULLUP);
    attachInterrupt(interruptPin, blink, CHANGE);
    startTime = millis();
}

void loop()
{
    //After 20sec will disable ISR for pin13
    if(millis() - startTime >= 20*1000)
        detachInterrupt(13);
   
    digitalWrite(ledPin, state);
}

detachInterrupt()

void detachInterrupt

(

uint32_t

pin

)

Description

Turns off the given interrupt

Syntax

detachInterrupt(pin);

Parameters

pin	the number of the interrupt to disable

Returns

void

Example

uint8_t ledPin = 36;
uint8_t interruptPin = 13;
volatile byte state = LOW;
long startTime = 0;

void blink()
{
    state = !state;
}

void setup()
{
    pinMode(ledPin, OUTPUT);
    pinMode(interruptPin, INPUT_PULLUP);
    attachInterrupt(interruptPin, blink, CHANGE);
    startTime = millis();
}

void loop()
{
    //After 20sec will disable ISR for pin13
    if(millis() - startTime >= 20*1000)
        detachInterrupt(13);
   
    digitalWrite(ledPin, state);
}

yield()

void yield

(

void

)