On Tue, 16 Sep 1997, Mark Dapoz wrote:

> > der Mouse wrote:
> >
> > [ to read the ROM, why not pull the chip? ]
> 
> [ the machine is a server and can't be taken down ]
> ... If I knew where the SPARC processor started executing
> when powered on, then that would isolate the ROM location.  Does anyone
> know what the startup sequence of the SPARC is?  The obvious vectors
> at the start and end of the ROM don't seem to provide any clues.

Unfortunately, knowing the the first address accessed by the SPARC cpu
when it is reset is still not likely to help you find the ROM address to
use once the machine is up and running the OS.  Many Sun machines have
logic glue chips that re-map the ROM so that it appears at the boot fetch
address when the machine powers up.  After the ROM code has taken
sufficient control of the machine, it turns off this remapping and runs
itself at its natural location.

Your best bet is to look at the various ``sunmon.h'' files scattered
around /usr/include in SunOS (and NetBSD.)  Look for either "PROM_BASE" or
"MON_START".

-J