Hi there

I was playing around with some long delays and
decided to get a formula for working out some of
the delays, instead of just trying random values
to get the desired delay.
The following code contains three loops with
different values. The code is called with the
value for DEL1 in w. This code includes the
call and return clock cycles in the formula.
Note that when F8 (step through) is used the
stopwatch shows an extra clock cycle, that
should not be there. If you step through the
delay you get the correct number of steps.

e.g..           SOME INSTRUCTION
                MOVLW   ??H <- use your DEL1 value
                CALL            DELAY1
                NEXT INSTRUCTION AFTER DELAY

DELAY1  MOVWF   DEL1
LOOP1           MOVLW   ??H <- use your DEL2 value
                MOVWF   DEL2
LOOP2           MOVLW   ??H <- use your DEL3 value
                MOVWF   DEL3
                DECFSZ  DEL3,F
                GOTO    $-1
                DECFSZ  DEL2,F
                GOTO            LOOP2
                DECFSZ  DEL1,F
                GOTO            LOOP1
                RETURN

The delay in clock cycles is:
 4*(1 + DEL1 + DEL1*DEL2) + 3*DEL1*DEL2*DEL3

Regards

Gavin
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vulcan@ihug.co.nz
http://www.geocities.com/TheTropics/Cabana/2625
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