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some newbie questions



section 6.8.1 in 68360 users manual says 
"second, the MBAR, newly located at address $0003ff04, can only be
enabled for access after a keyed write operation is performed" and later
on there is described that one has to write FFFFFFFE to MBARE before
MBAR could be set. even if that section talks about multiple QUICC
slaves : could this be the problem ?

regards,
seb

On Thu, 19 Feb 2004 14:35:53 -0500
Ed Sutter <els at emailbox.hdtv.lucent.com> wrote:

> Nevermind!!!
> I just scanned futher through the manual and it appears that the first
> instance of the MBAR address has a typo.  All other references in the
> manual use 0x3ff04, not 0x33ff04.
> Sorry about that!
> Ed
> 
> sebastian ssmoller wrote:
> > 
> > hi,
> > finally i used the approach: incrementing a variable an see where it
> > stops.
> > 
> > > Seb,
> > > Just reset the board (don't powercycle).  In most cases this
> > > doesn't
> > > corrupt memory.  Usually, assuming you have a reset or NMI type
> > > of button, you can get yourself back to the monitor, then in RAM
> > > space you essentially have the equivalent of a core dump.
> > 
> > i did so and it worked perfectly well.
> > 
> > i started debugging at c/src/lib/libbsp/m68k/gen68360/start/start.S
> > where the start symbol which i call is defined. i found out that the
> > board hangs immediately at step 4 where mbar is set.
> > 
> >   /*
> >    * Step 4: Write the MBAR
> >    */
> >     movec   dfc,d1          | Save destination register
> >     moveq   #7,d0           | CPU-space funcction code
> >     movec   d0,dfc          | Set destination function code register
> >     movel   #m360+0x101,d0  | MBAR value (mask CPU space accesses)
> > /* with the execution of the next line the board will hang */
> >     movesl  d0,0x3FF04     | Set MBAR
> >     movec   d1,dfc          | Restore destination register
> > 
> > the original addr of the MBAR was 0x3ff00 as described in the 68360
> > manual (which failed). i read again the doc of my board and it says
> > that
> > MBAR is at 0x3ff04. so i changed the value but nothing happens - the
> > board still hangs :(
> > 
> > thx
> > 
> > regards,
> > seb
> > 
> > (...)--
> > Microsoft: Where do you want to go today?
> > Linux: Where do you want to go tomorrow?
> > FreeBSD: Are you guys coming or what?
> > OpenBSD: Hey guys you left some holes out there!
> 


-- 
Microsoft: Where do you want to go today?
Linux: Where do you want to go tomorrow?
FreeBSD: Are you guys coming or what?
OpenBSD: Hey guys you left some holes out there!