I am planning to use the AN654 code for software PWM.  I was wondering
why the btfsc instruction is included at the start of the ISR:

   ORG 04h ; timer interrupt
    btfsc TMR0,0 ; compensate comp time of 1/2 cyc
    goto PwmInt ; instruc when timer int occured
    PwmInt
    movwf STACKW ; copy W register... to "stack"
    ...

I have seen an article on PICList by Bob Ammerman explaining that this
will "eliminate jitter on the interrupt timing.  Looking at the PICMicro
Reference Manual, it appears that the timer should be at 0x02 when the
first instruction of the ISR is executing due to a timer0 interrupt (i.e.
the goto will always be skipped).  Am I missing something?

Thanks in advance,

Pete

...

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