Processing pre-set Interrupts

I am having troubles with my encoder. It is a 128 ppr encoder, and at close to maximum shaft RPM, I start to get bad readings from it. I figured this was from the RC trying to process too many interrupts per second, so I know I need decrease the ppr of the encoder.

The way I thought I could do this was by including a true/false check statement in the InterruptHandlerLow() function that would only call the Encoder Handler Function every other time that interrput happened. I tried doing this with if’s and switch statements, but neither worked. I still got 128 ticks per revolution.

Heres a sample of the code I am using.

unsigned char loops=0;

void InterruptHandlerLow()     
         if (INTCON3bits.INT2IF && INTCON3bits.INT2IE) // left encoder interrupt?
			INTCON3bits.INT2IF = 0; // clear the interrupt flag [91]
			Left_Encoder_Int_Handler(); // call the left encoder interrupt handler (in encoder.c)
     else loops=0;

Any ideas?

Check the magical Encoder FAQ for a possible answer.