gnupic: Re: [gnupic] Relocatable support (Was: Re: [gnupic] SPASM - a MPASM behave alike)
Subject:
Re: [gnupic] Relocatable support (Was: Re: [gnupic] SPASM - a MPASM
behave alike)
From:
David Barnett ####@####.####
Date:
8 Jun 2009 01:45:32 -0000
Message-Id: <4d52f78b0906071845m7f7ae744y4ad9628595d3cc00@mail.gmail.com>
On Sun, Jun 7, 2009 at 4:58 PM, Holger Rapp ####@####.#### wrote:
> [...] I am kind of interested in the mechanics of relocatable code. Could
> you provide some insight into new style coff (-C option to gpasm) and old
> style coff?
I'm not sure myself what *all* of the difference is, but I think there are a
couple of extra bytes in some of the fields in the new style (and 0x1240 is
the magic number for the new style, I think). The biggest reason I've seen
for supporting new-style coff is that it's what recent versions of MPASM
generate, so for the linker and gpvo it's good to support both. However, for
the assembler just supporting one or the other should be fine for now, and I
think it should be extremely easy to add the other later.
There are some structs in the gputils code that might clear some of those
binary formats up for you if you want to go looking for them.
BTW, have you seen the intelhex module in python (
http://bialix.com/intelhex/). The HEX format isn't too complicated, so it
might not be worth the extra dependency, but I just wondered if you'd seen
it yet...
David
