attached the code, I hope somebody can see what's wrong!!

thank you.
 ----
From: myke predko <myke@PASSPORT.CA>
To: PICLIST@MITVMA.MIT.EDU
Date: 16 May 1997 6:45 AM
Subject: Re: TMR0 interrupt (PIC16c84 and PWM)

>Osama wrote:
>>the *ACTUAL* code is at the uni (closed Thursdays and Fridays :(  )
i'll
>>get it on Saturday and post it...
>>
>>it does run on the simulator. (this is what puzzles me most! shouldn't
>>MPSIM be fully compatible with the real thing?)
>
>What I mean to say there are a lot of cases where the simulator seems to
>indicate that something is working, but when you get out into the real
>world, it upchucks.
>
>Last year, I spent about three weeks trying to nail down a problem that
>worked fine in the simulator, but when I actually tried it out on
hardware,
>the device just sat there and did nothing.  I finally traced the problem
to
>how I was simulating it, I had a delay routine that I skipped over in the
>simulator because it took about an hour and a half to run (it delayed the
>PIC for about 3 seconds).
>
>The problem ended up being that the interrupt routine that I was
debugging
>was active during this delay, but needed variables which were initialized
>*after* the delay routine.  It worked fine when the delay routine was
>skipped and the interrupt didn't happen until after the variables were
>initialized, but wouldn't work at all when the delay routine was working.
>
>It didn't matter how hard I stared at it - it worked fine in the
simulator
>and wouldn't work in the device.  Maybe this is a case that would be
>immediately obvious if you had an emulator.
>
>
>Just reviewing this and realizing there is one MAJOR difference between
>MPSIM (and MPLAB-SIM) and a real PIC.  That's in how the registers come
up
>initialized.  In both simulators, they are initialized to 0x000 and in
the
>PIC, they can be anything.
>
>I just went back to your original note and I'm thinking that this is
>probably your problem.  In the code you wrote, you didn't show how the
PWM
>variables were initialized.  I suspect that you probably don't initialize
>PWMCounter (because it shows up as 0x000 in the simulator) and when you
run
>your code it's actually greater than the test values (and nothing ever
gets
>output).
>
>
>Just a question for everybody who's used a PIC emulator more than I have
>(because I didn't think to look for this when I was lent a PICMaster),
what
>do the Register Values initialize to?
>
>
>When you get the code, we should be able to find the problem,
>
>myke
>>
>>thanks.
>> ----
>>From: myke predko <myke@PASSPORT.CA>
>>To: PICLIST@MITVMA.MIT.EDU
>>Date: 15 May 1997 23:46 PM
>>Subject: Re: TMR0 interrupt (PIC16c84 and PWM)
>>
>>>Osama,
>>>
>>>Could you please post the *actual* code?  I find that little problems
in
>>>assembler that screw up the whole program can be stared at for hours by
>>the
>>>author without seeing them.
>>>
>>>As well, have you run your code through the simulator (my first line of
>>>defense/verification before I burn a part)?
>>>
>>>myke
>>
>>
>
>"My ancestors didn't spend millions of years clawing their way to the top
of
>the food chain, just so I could become a vegetarian"
>

Content-Type: application/octet-stream;
        name="Pwm.asm"
Content-Disposition: attachment;
        filename="Pwm.asm"

Attachment converted: wonderland:Pwm.asm (????/----) (00002DF8)