John Payson wrote:
>
> > Unfortunately, it also destroys W which forces subroutines to return
> > results in registers.  There are plenty of solutions.  How about the
> > following untested macro for general calls.  No doubt Andrew Warren et
> > al. have something similar in their web pages, but this is my 5 cents
> > worth (sorry, Oz doesn't have 2 cents any more - inflation, you know).
>
> Is there any particular problem with placing critical code such as
> interrupt handlers at both addresses [$0004 and $0804]?  I realize
> that normal assemblers do not [yet] accommodate this, but it would
> seem like a simple hex-file post-processor should take care of it
> very nicely.  Alternatively, if most of the code is used for table
> storage, it might be possible/practical to duplicate all of the
> real "code" and just use PCLATH to reference the tables.  Any
> thoughts on this notion?

I like to save PCLATCH at 0x0004 (Int vector) and then restore it before
retfie - ing. It works OK.
--
Friendly Regards

Tjaart van der Walt
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