M9312 boot rom ID help?

[Lyle Bickley]

On Friday 15 July 2005 19:23, Jay West wrote:
> Lyle wrote....
>
> > Load and Examine 773000, 773200, 773400 and 773600 (for each Prom
> > address):
> >
> > The first three digits:
> > 040=A
> > 041=C
> > 042=D
>
> Oh Neat! I did read a section in the M9312 manual which shows a list of the
> contents of location 773000, 773200, 773400, 773600 and shows what rom
> those values are for. However, they don't say in the manual that they are
> ascii, I figured it was just some unique word (checksum or somesuch) at the
> beginning and hence wouldn't be a good technique to see what any (unlisted)
> boot prom was for. I should have noticed :> Thanks for pointing this out!
>
> Jay West

Yes, it's interesting that it isn't documented (at least anywhere I could 
find.)  What's weird is that the first three digits are "coded" and the last 
7 bits are ASCII.  Probably has something to do with the way the PROMS are 4 
bit "compressed" format or something.  I just happened upon the decoding 
"scheme" while trying to figure out what a bunch of PROMS were that I 
had.  ;-)

Lyle
-- 
Lyle Bickley
Bickley Consulting West Inc.
Mountain View, CA
http://bickleywest.com

"Black holes are where God is dividing by zero"