On Tue, Jan 25, 2005 at 08:12:02AM -0500, Olin Lathrop wrote:
> William Chops Westfield wrote:
> >So we have:
> >
> >equ symbol values assigned by user at asm time
> >cblock  symbol values assigned by assembler at asm time
> >res symbol values assigned by linker at link time
> >
> >Is that correct?
> 
> Yes!  Another important point is that the symbols defined with RES only
> refer to RAM locations.  Symbols defined with EQU and CBLOCK are just
> ordinary constant with no inherent connection to RAM locations.

Very true. And when programming in absolute mode I've been bitten by that
fact. When migrating up from the 16F84, whose 1st non SFR RAM location is
at 0x0C IIRC to the 16F877, whose 1st non SFR location is at 0x20.

Nothing about a CBLOCK would alert you to this.

Olin thanks for your very pointed and moving posts on the subject.

Since I have found clear cut examples in the GPUTILS Relocatable Object
Howto located here: http://gputils.sourceforge.net/reloc_howto.html I
guess it's time to start swimming in the deeper end of the pool.

A quick Google located this MPLINK tutorial PDF:

http://www.engj.ulst.ac.uk/sidk/PIC/mplink_tut.pdf

It has a 17C44 target but gets the point across.

BAJ
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