Hello Hasan,

I think I have found the problem. The CCP module in capture mode uses timer1
as a resource. You haven't properly configured timer1, though you are
turning it on and off. In the 16F628 datasheet read up on timer1 and its
control register T1CON. You need to select a prescaler value, clock source,
and there are a few other bits to check.

The bit in T1CON you overlooked is called T1OSCEN. This enables or shuts-off
the oscillator for the timer.

I also have a comment about the code:

In the detectFor65ms() function I think you should order some of the
statements differently. Here is a part of that function's body:

        TMR1ON = 0;
        CCP1CON = 0x05;

        TMR1IE = 1;
        CCP1IE = 1;
        PEIE = 1;
        GIE = 1;
        timeout = 0;
        detected = 0;
        TMR1ON = 1;
#if defined DEBUG
        TMR1L = 0xe0;
        TMR1H = 0xff;
#endif
        TRISB = 0b00001000;

I think you should initialize everything _before_ enabling the
interrupts. As it stands now, it is possible for a capture interrupt to
occur before the variables timeout and detected are set to zero! That means
you could miss your compare event. I would organize the above code like
this:

        TMR1ON = 0;
        CCP1CON = 0x05;
        TRISB = 0b00001000;

#if defined DEBUG
        TMR1L = 0xe0;
        TMR1H = 0xff;
#endif

        timeout = 0;
        detected = 0;

        TMR1IE = 1;
        CCP1IE = 1;
        PEIE = 1;
        GIE = 1;

        TMR1ON = 1;

When I encounter a problem like this I do two things (in this order). One,
read the datasheet throughly; be absolutely certain you understand
everything about the module you are using. Second, re-write the code, in as
simple a manner as possible, to do only thing you're having trouble with (in
your case, get rid of the timeout stuff and concentrate on the CCP module).

I hope this helps you. There may be someother problems with your code that
I've not found; I've never used the CCP module before.

Good luck, Matthew.

-- 
Memory is like an orgasm. Its a lot better if you dont have to fake it.
 -- Seymour Cray, commenting on virtual memory
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