Morgan Olsson wrote:

> I have always wondered why Micrichip wasted silicon and instruction
> codes on

> CLRW    ( = ANDLW 0 )
> NOP     ( = BSF or BCF unused/unimplemented bit )
> TRIS    ( = MOVWF  (Mchip recommends not to use TRIS no more anyway) )
> OPTION  ( = MOVWF  (Mchip recommends not to use OPTION no more anyway)
  I trust you have analysed these codes and considered what they mean?
CLRW is actually "CLR INDF,W" while TRIS and OPTION are three and one
members respectively of a group of "control" codes of which only a total
of seven out of sixteen (including NOP) are allocated anyway.

  In fact only seven out of 32 codes in the %0000 00x xxxx class are
allocated overall.  Why be so concerned about TRIS and OPTION?

  As to NOP, this is non-negotiable.  This is the code equivalent to NUL
on a teletype tape; any instruction can be deleted completely by over-
progeramming to NOP.
--
  Cheers,
        Paul B.