Ok, this time with the question...

How should contexts be safely saved in a low priority interrupt when a high 
priority interrupt is also used (on a pic 18f)?
The examples given in various datasheets and the example template are shown 
at the end, but I have also read that it is not a good idea to use the movff 
instruction if an interrupt could occur in the middle (of the movff 
instruction). Therefore if high priority interrupts are enabled, surely it 
would be safer to save contexts this way:


LowInt:
    movwf     WREG_TEMP
    swapf      STATUS,W
    movwf     STATUS_TEMP
    movf        BSR,W
    movwf     BSR_TEMP

and restore them this way:

    movf       BSR_TEMP,W
    movwf    BSR
    swapf     STATUS_TEMP,W
    movwf    STATUS
    swapf     WREG_TEMP,F
    swapf     WREG_TEMP,W
    retfie

or am I being unnecessarily cautious ?

Thanks,
James


HI_INT_VECTOR CODE 0x0008
    bra     HighInt          ;go to high priority interrupt routine


LOW_INT_VECTOR CODE 0x0018
    bra     LowInt          ;go to low priority interrupt routine

CODE

HighInt:

; *** high priority interrupt code goes here ***

  retfie FAST


LowInt:
    movff      STATUS,STATUS_TEMP ;save STATUS register
    movff      WREG,WREG_TEMP  ;save working register
    movff BSR,BSR_TEMP  ;save BSR register

; *** low priority interrupt code goes here ***

    movff BSR_TEMP,BSR  ;restore BSR register
    movff WREG_TEMP,WREG  ;restore working register
    movff STATUS_TEMP,STATUS ;restore STATUS register
    retfie 

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