Hi Rikard,
here find an example of how you can solve your problem.
The code is self explaining...
You can change the goto with retlw of course but not the order of the 
instructions that do the jump!
Bye
           Nic

;************************
starthere
    movlw    high(JumpTable)    ;load high address byte in PCLATH
    movwf    PCLATH

    movlw    JumpTable
    addwf    TableIndex,w      ;TableIndex from 0 to number of items -1

    btfsc    STATUS,C          ;check Carry flag
    incf     PCLATH,f          ;gotcha!

    movwf    PCL               ;now jump safely

JumpTable
    goto    FirstPoint
    goto    SecondPoint
    goto    ThirdPoint
JumpTableEnd
;*********************

Rikard Bosnjakovic wrote:
> Consider this code:
>
> default_minutes:
>         addwf   PCL, f                          ; jump table
>         retlw   .5
>         retlw   .10
>         retlw   .15
>         retlw   .20
>
> When it was in the beginning of my code, PCL was below 0xff, it
> worked. When tidying my code I moved the above to the bottom of the
> source, and the code went totally havoc. After 20 minutes of
> debugging, I found that two lines before it, PCL overflowed and turned
> into 0x00, making the jump-table return a value which made the goto go
> to the beginning of the code!
>
> It's easily solvable by moving "default_minutes" to a place near the
> top of the source, but is there any way you can solve it in other
> ways? I mean, since the chip (16F886) got 8kb program stack, PCL must
> be able to keep track of all 8kb data.
>
>
>   

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