In a message dated 31/12/97  11:21:25, you write:

<<
 What I have is an input that reads '11010000' say. What I need to do is
 convert it to '00001101' say.

 One route seems to be to RRNCF four times. Would this do the job and not
 affect any other registers?
  >>
Philip thats ok if you are using 17cxx devices but the instruction dosent
exist on 12,16cxxx devices consequently first preserve carry if required then
rrf four times will get to the same place

somthing like
RRF     ANYREG,F
RRF     ANYREG,F
RRF     ANYREG,F
RRF     ANYREG,F
CLRC                         ; CLEAR GARBAGE FROM CARRY
BTFSC ANYREG,4      ; CHECK SEE WHAT CARRY WAS
SETC                         ; RESTORE IF REQUIRED.

Sounds like it should work u dont need to save carry during manipulation as it
is used but appears in bit 4 however the upperbits are not in the corect place
but this is only important if they are needed.

Sorry all the above is bollox

SWAPF   ANYREG,F    ; does exactly what you want in a single instruction
without affeactin any status bits.............

Cheers Steve