gnupic: Re: [gnupic] gpasm macros/defines
Subject:
Re: [gnupic] gpasm macros/defines
From:
"Tamas Rudnai" ####@####.####
Date:
18 Nov 2006 02:25:23 +0000
Message-Id: <492f1420611171825j7c4c6d91m52f741e5e3b75036@mail.gmail.com>
Sorry again, just seen the first message:
MY_MAC macro
endm
...
#ifdef MY_MAC
MY_MAC
#endif
Again, MY_MAC macro is a macro definition for the compiler, #ifdef is used
by the preprocessor. Pre-processor, so runs first, therefore checks if
MY_MAC is defined by #define or not. But it is not... therefore leaves out
the body so the compiler will not even receive that line.
Hope it helps,
Tamas
On 11/18/06, Tamas Rudnai ####@####.#### wrote:
>
> Hiya,
>
> Maybe I just don't get it. #define handled by the preprocessor, while
> macro by the compiler itself. So what happens here is that first
> preprocessor idetifies that you defined OP1 as the string 'movlw X' then
> replaces the source code where you write OP1 to that string. The compiler
> then will get this input:
>
> START1 MACRO X
> ENDM
> ...
> START1 5
> movlw X ;
>
> (#define removes as processed by the preprocessor, START1 is an empty
> macro, and OP1 is the string replaced by the preprocessor)
>
> You would need something like that:
> #define OP1 START1 5
>
> START1 MACRO X
> movlw X
> ENDM
> ...
> OP1 ;
>
> Tamas
>
>
>
> On 11/17/06, David Barnett < ####@####.#### wrote:
> >
> > ----- Original Message -----
> > From: "David Barnett" < ####@####.####
> > To: ####@####.####
> > Sent: Wednesday, October 18, 2006 3:55 PM
> > Subject: Re: [gnupic] gpasm macros/defines
> >
> >
> > > ...
> > > With the other problem, I might be able to combine assembler variables
> > and
> > > #defines to work around it...
> > >
> > > Is there any good reason for not expanding macro parameters in define
> > > statements contained within the macros? Or is there some kind of
> > standard
> > > that unambiguously defines the correct behavior?
> >
> > I thought I had a workaround for this define/arg expansion problem:
> > START1 MACRO X
> > #define OP1 movlw X
> > ENDM
> > ...
> > START1 5
> > OP1 ; gpasm reports "symbol not previously defined (X)."
> > but it turns out there are problems with it, too. I'm getting kinda
> > desperate for advice here. Scott, have you gotten in deep enough with
> > gputils to know anything about this?
> >
> > David
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: ####@####.####
> > For additional commands, e-mail: ####@####.####
> >
> >
>
>
> --
> unPIC -- The PIC Disassembler
> http://unpic.sourceforge.net
--
unPIC -- The PIC Disassembler
http://unpic.sourceforge.net
