Hello,
   I am working on a Digital Calendar based around a PIC16F877
   operating at 20MHz, for part of my degree project.  My deadline is
   only a few weeks away, and I have been coming up against what seems
   to be an infinite loop for the past few weeks.
   I have written smaller test programs to try and ascertain the cause
   of the problem, but so far with no luck.
   Yet if I step through the code using MPLAB 5.11's simulator, it
   appears to return from the particular sub-routine correctly.
   The point in the code where it appears to simply stop is in the RTC_DELAY
   sub-routine.
RTC_DELAY
        MOVLW   D'254'
        MOVWF   DELAY_COUNT     ;set counter value
RTC_DELAY_LOOP
        DECFSZ  DELAY_COUNT,F   ;dec delay_count, is zero? if yes, skip next
        GOTO    RTC_DELAY_LOOP  ;no, else loop
        RETURN                  ;yes, return

   It's a very simple routine, and I can't see how it is failing,
   though I am currently worried about completing on time, at all.

   I am using an ICEBreaker In-Circuit Emulator from Magenta
   Electronics (with the ICEBreaker programming and monitoring
   software), with a PIC16F877, interfacing with a DS1302 Real-Time
   Clock.  Using MPLAB 5.11 for development/simulation/assembling.
   I can include the test programs and full program source if
   necessary.
   Any help would be greatly appreciated.  For this part, I am simply
   trying to write-to and read-from the Real-Time Clock chip.
--
All the best,
 Glenn Davidson

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