Setting up CCP1 interupt

[chris414]

I'm trying to set up an interupt to trigger when there is a falling edge on my CCP1 pin (I'm using a PIC18F4550). If I poll for the interupt bit to be set (just run a loop waiting for PIRbits. to go high) everything works. However when I try to use an ISR I get no response.

I am using one of microchip's application notes with USB, and they have a method called "YourHighPriorityISRCode()" which I am using (the comments are from microchip):

	//These are your actual interrupt handling routines.
	#pragma interrupt YourHighPriorityISRCode
	void YourHighPriorityISRCode()
	{

		if(PIR1bits.CCP1IF == 1){
			alpha = 1;
			PIR1bits.CCP1IF = 0;
		}

		//Check which interrupt flag caused the interrupt.
		//Service the interrupt
		//Clear the interrupt flag
		//Etc.
        #if defined(USB_INTERRUPT)
	        USBDeviceTasks();
        #endif


	
	}	//This return will be a "retfie fast", since this is in a #pragma interrupt section

Anyway ideas why it's not working? I've tried adding an "else" statement which by my understanding should have been triggered every time an interrupt was received, but I got nothing.

 

[chris414]

Nevermind I got it working - for some reason high priority interupts weren't enabled in the INTCON register