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Re: Developing 68332 system with gcc and gdb.


> > Has anyone patches for gdb, which allow me debug any program
> > on board (through bdm)?
> 
> There is a file called gdb-4.16-bdm-patches.tgz which includes patches
> for gdb-4.16 to operate via bdm. It includes schematics for a bdm
> interface. 

ftp://ftp.lpr.e-technik.tu-muenchen.de/pub/bdm/gdb-4.16-bdm-patches.tgz 

> BUT: It will only work if gdb is able to upload the code
> via bdm. So you _need_ to have RAM properly connected to /CSBOOT if
> you want to avoid kludges like having an EPROM on /CSBOOT which
> set up things and jumt into RAM afterwards.

???

It is definately not necessary to connect _RAM_ to _CSBOOT_. And you don't
need a startup ROM for debugging via BDM and gdb. 

Of course, you need RAM to download code, but you can control it with _any_
CS line(s). Just configure them before download. If you have sufficiently
small programs, you can perfectly use the internal 2K RAM, and start on a
minimal system consisting of 332, clock, power-supply and bdm connector.

If you have a valid monitor in your startup ROM, you can take advantage of
that for system initialisation, e.g. clock config, CS config, etc. Use the
bdm_timetocomeup option, maybe in combination with bdm_autoreset. With
that, after a reset the processor runs ROM code, and after a setable time,
gdb stops it and enters BDM mode. After that, you can load your code.

If you have a ROM-less system, use the pre-download macros. There are
examples in the above mentioned package for the BCC. With the macro
facility, you can configure your target in virtually any respect, thanks to
memory mapped peripherals.

greetings
gm
-- 
Gunter Magin                                         magin[AT]skil.camelot.de