Nice job with the:

incf FILEREG,  F
dcfsnz FILEREG, F
; here if zero
; here if not zero

hitech dude
I figure he is either calling a routine or setting a bit or byte
in which case something like:

if you want X<0>=0 if FILEREG=0 or X<0>=1 if FILEREG=1

bcf X, BIT                              ; X<BIT> = 0
tstfsz FILEREG, F                       ; skip if FILEREG = 0
bsf X, BIT                              ; X<BIT> = 1

is far superior and with no intermittent side effects



On Sun, 23 May 1999, Jamil J. Weatherbee wrote:

> Lame I agree.  But the 17Cxxx are built so you don't really need to use
> that instruction of using the appropriate paradigm.
> Here is a low efficiency replacement:
>
> COMF FILEREG, F
> COMF FILEREG, F
>
>
> On Tue, 25 May 1999, TYR130010 wrote:
>
> > Hello all, I am a recent convert to PIC devices, and writing for 17C756.
> >
> > I have noticed one particularly irritating short coming;
> > you can't do an equivalent: MOVF  "FILEREG",F in the 17C devices
> > like you can in the 16C devices  to change the Z flag.
> >  The TSTFSZ works if you want to Skip on zero, but there is no
> > complementary "TSTFSNZ" instructions.
> > The nice thing about the TSTFSZ is it affects only the Z flag, and no
> > other registers or flags.
> >
> > Maybe there are some old hands who have created macros that do the
> > job as efficiently as possible with minimal impact on, or disturbance
> > to any registers who wouldn't mind sharing them with everyone.
> >
> > Or if not, maybe a little game perhaps, to see who can come up with
> > the neatest, most useful, compact, and documented ( so everyone can -
> > - understand  ) macro?
> >
> > I feel this would be a very useful subject for novice programmers.
> > While we're at it, we might as well cover some of the ground rules
> > for use of Macro's, such as you don't use them immediately after a
> > "Test and Branch" instruction for obvious reasons.
> >
> > I will venture this "glove" in the spirit of being taught my place.
> > You never know I just "might" learn something new ;)
> >
> > This macro started as a joke, but it does with W what the complement
> > of  TSTFSZ  WREG  would do .
> >
> >                     ; Tests WREG without disturbing it, and only affects
> > Z flag.
> > TSTWSNZ     MACRO
> >                     IORLW    00H                  ; Won't affect value
> > in W
> >                     BTFSC    ALUSTA,Z        ; SKIP IF W <> ZERO
> >                     ENDM
> >
> >
> > hfoster@tyler.net
> >
>
>