Hi. Just a quick check here. In the example as shown in
example 5 in AN556 (Table reads), and as copied below,
what if the "offset" is h'00' initialy ? Would not
the addwf instruction marked (1) give the address of the
movwf instruction marked (2) ? And the movwf instruction
marked (2) would then just reload the address of itself,
creating a loop ? The offest would have to be h'01'
(at least) from the beginning, or ?

I'd expect a second label right before the first retlw instruction
that would be used in the offset calculation in the addwf marked (1).

I might be missing something...

A second thought...
Would it not be better to move the address calculation
*inside* the subroutine, so you don't have to dublicate
the offset calculation everytime the table is called ?
I can't see any problem with this.

Jan-Erik.


  org 0x80

  movlw     LOW Table    ;get low 8 bits of address
  addwf     offset,F     ;do an 8-bit add operation         (1)
  movlw     HIGH Table   ;get high 5 bits of address
  btfsc     status,c     ;page crossed?
  addlw     1            ;yes then increment high address
  movwf     PCLATH       ;load high address in latch
  movf      offset,w     ;load computed offset in w reg
  call      Table


  org 0x9FD

Table:
  movwf     PCL,F        ;load computed offset in PCL       (2)
  retlw     'A'          ;return the ASCII char A
  retlw     'B'          ;return the ASCII char B
  retlw     'C'          ;return the ASCII char C

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