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External Interrupt Always Running?
I’m tring to implement an external interrupt on D2 on a Nano 3.0/328 that does other things. When the interrupt is triggered, it calls Timer1. When I enable the interrupt to activate on a falling edge, I can no longer get ethernet communication working. Does the external interrupt continuously poll for the D2 pin change state? Is is possible to run other stuff (ethernet, LCD, timer stuff) when the interrupt has not activated?
I assume I just don’t know what I’m doing. Any guidence on properly setting up the external interrupt so my other code will run correctly is appreciated.
Interrupt Activation Code (From Nick Gammon’s site):
Code:
pinMode(2, INPUT); // Set Interrupt 0 (Pin 2) To Input Mode
digitalWrite(2, HIGH); // Enable pullup resistor
sei(); // Enable global interrupts//Gammon Code
EICRA amp= ~(_BV(ISC00) | _BV (ISC01)); // clear existing flags
EICRA |= _BV (ISC01); // set wanted flags (falling level interrupt)
EIMSK |= _BV (INT0); // enable itISR code:
Code:ISR(EXT_INT0_vect)
{TCCR1A = 0; // reset timer 1
TCCR1B = 0;// set up Timer 1
TCNT1 = 0; // reset counter
OCR1A = g_timerCounter; // compare A register value
TIFR1 |= _BV (OCF1A); // clear interrupt flag
TIMSK1 = _BV (OCIE1A); // interrupt on Compare A Match}
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