23 Apr
2016
23 Apr
'16
9:33 a.m.
But from the discussion referred I gather DROM
outputs its diagnostics to
this port too and you might be able to learn what exactly about NVRAM it
complains. Also you might be able to correct configuration, e.g. by
poking at
NVRAM or elsewhere appropriately; notice that the
manual also suggests
you might be able to bypass the DROM sequence and go to SRM/ARC
directly, which might help recovery too.
Having checked the manual I think you may be referring to the following
text:
" When the SROM code has completed its tasks, it normally loads the DROM
code and
turns control over to it. The SROM checks to see if the DROM contains the
proper header
and that the checksum is correct. If either check fails, the SROM code reads
a location in
the TOY NVRAM. The location indicates which console firmware (the SRM or the
ARC)
should be loaded.
When the console firmware is loaded, the header check and the checksum are
checked. If
either is in error, the SROM code jumps to its mini-console routine. With
the appropriate
adapter, you can attach a terminal to the CPU's serial port and use the
mini-console.
Typically, this port is used in the manufacturing environment."
To get this sequence to work needs two things though. First I have to create
a DROM error. The DROM seems to be fine. Perhaps I could remove the DROM
chip as it is socketed to provoke the error.
However, then it says it checks the TOY NVRAM for which firmware to load.
The battery was flat, so the TOY NVRAM won't have this info. Hopefully it
will default to one of them.
Still, if I had the mini-console adapter, that would probably really help.
Regards
Rob