MVME162 RTEMS exit(0) actions/control

[Joel Sherrill]

Ken Fitch wrote:
> 
> I've successfully (I think) built RTEMS 4.5.0-beta3 for a Solaris
> 2.5.1 host and a MVME162 target (after some messing around with
> workarounds for problems in the build procedures).
> 
> For historical reasons, the MVME162 board is configured
> to use serial port 2 for the MBUG interface.  If I build the
> hello_world_c program, edit the S8 S-record to avoid immediate
> execution, download the resulting test.exe using MBUG (162-Bug)'s "LO"
> command, and then run the program with a "G 100000", it does write out the
> expected messages to serial port 1, but then continues to spew hex data
> until ultimately the processor stops (apparently because the code gets
> overwritten).
> 
> What is the expected behavior when the exit(0) call is made?  I expected
> (probably without any basis) that the appropriate trap call to get me
> back to the 162-Bug> prompt would happen.  I didn't expect to see data
> coming out the serial port.
> 
> I scanned the mailing list archives on the old OAR site, but didn't
> find anything I thought was relevant.
> 
> Is this indicative of a problem in the installation/build or with the
> MVME162 board configuration, or with my lack of experience/understanding
> with/or RTEMS?  If it's the latter, what should I be reading to explain
> it all to me?

It should go back to the mbug prompt.  On many BSPs, you could then 
reexecute the application but that is not necessarily guaranteed.

Look at the file c/src/lib/libbsp/m68k/mvme162/startup/bspclean.c and
see if that is broken.  That is the final exit path back to mbug.

> Info about the target system:
> 
> 162-Bug>cnfg
> Board (PWA) Serial Number = "2039983     "
> Board Identifier          = "PWB-MVME162-020A"
> Artwork (PWA) Identifier  = "01-W3884B65B    "
> MPU Clock Speed           = "2500"
> ...
> 
> Ken Fitch

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