re Basic questions re RTMS and PPCbug

[Joel Sherrill]

David Hamilton wrote:
> 
> Thanks for the replies Joel, Gregory and Tom.
> 
> I tried using the PPCbug command NBO to boot hello.exe (from
> /opt/rtems/mvme2307/samples) over the network. This gave a similar result to
> the combined NIOP and GO command I had used before.
> i.e.
> Program transfers over ok but produces "Exception: Program (Illegal
> Instruction)"  and prints register contents on execution.
> 
> I don't know if there is something in it, but I looked around for other
> copies of hello.exe (as Gregory suggested) and found that /opt/rtems/mcp750
> (which I also installed) had an extra directory (compared to
> /opt/rtems/mvme2307) called bin, which has a much smaller hello.exe file
> (~120k versus 1.1M).
> I tried booting this file (although the MCP750 board is significantly
> different from an MVME2700), and it loads and then hangs (which seems more
> promising than the other as it maybe implies that it starts executing and
> then hangs when trying to communicate with an incompatible device).

That sounds very reasonable.  The question to ask now is ... what is the
different between a mvme230x, mcp750 and, and mvme270x. The answer will
very likely point at a very specific area of code.  The README has some
notes
on board variations and some places in the code that make decisions
based upon
reading some board configuration information. That would be a good place
to
peak first. :)

> Perhaps the files in /opt/rtems/mvme2307/samples are not quite ready to be
> loaded yet. Hmmm!

Offhand, I do not know whaqt format they are in.  If they are Srecords,
then
they would be downloaded via a different procedure and would tend to be
on the order of about 2.5 times bigger than the .bin files.  Some BSPs
provide
a secondary format for the .exe's and don't install it.  That is the
case here.

> I'm going home now (its 7:30pm in the uk) and I'll be away next week so I
> have to put my investigations on hold for a bit.
> 
> David

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel at OARcorp.com                 On-Line Applications Research
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