[comp.sys.mac.hardware] What do Rev B ROMs do?

brod@jessica.Stanford.EDU (Brodie Lockard) (06/04/91)

What do the Rev B ROMs in a Mac II do that the Rev A ROMs did not?
Didn't this upgrade have something to do with 32-bit addressing?
What's the difference between a Rev B ROM upgrade and the upgrade
everyone wants Apple to provide to allow 128MB of RAM?

Brodie Lockard
brod@jessica.stanford.edu

Brodie Lockard      brod@jessica.stanford.edu

tgoose@eng.umd.edu (Jason Garms) (06/05/91)

In article <1991Jun3.211128.13792@leland.Stanford.EDU>, brod@jessica.Stanford.EDU (Brodie Lockard) writes:
> What do the Rev B ROMs in a Mac II do that the Rev A ROMs did not?
> Didn't this upgrade have something to do with 32-bit addressing?
> What's the difference between a Rev B ROM upgrade and the upgrade
> everyone wants Apple to provide to allow 128MB of RAM?
> 
> Brodie Lockard
> brod@jessica.stanford.edu
> 
> Brodie Lockard      brod@jessica.stanford.edu

The major feature that I know of is it allowed you to address more NU BUS
cards with more than 1 MB of RAM.  Rev A ROMs wouldn't work with these cards.

For the record.  This was a free upgrade from Apple if you could show proof
of purchase of a product that needed the new ROMs.

Have a good day,
Jason Garms
tgoose@eng.umd.edu

DON.NOLL@p3425.f421.n109.z1.FidoNet.Org (DON NOLL) (06/05/91)

BL> What do the Rev B ROMs in a Mac II do that the Rev A ROMs did not?
BL> Didn't this upgrade have something to do with 32-bit addressing?
BL> What's the difference between a Rev B ROM upgrade and the upgrade
BL> everyone wants Apple to provide to allow 128MB of RAM?
BL> 
BL> Brodie Lockard
BL> brod@jessica.stanford.edu
BL> 
BL> Brodie Lockard      brod@jessica.stanford.edu

On of the things the REV B roms do is allow a NUBUS card to access more than 1 meg of ram each.  This helps you if you have a video board with gobs of memory or a NUBUS memory card for AUX.
 * Origin: Don's Point, Get it? (1:109/421.3425)

sgrae@megatest.UUCP (Steve Graesser) (06/05/91)

From article <1991Jun3.211128.13792@leland.Stanford.EDU>, by brod@jessica.Stanford.EDU (Brodie Lockard):
> What do the Rev B ROMs in a Mac II do that the Rev A ROMs did not?
> Didn't this upgrade have something to do with 32-bit addressing?
> What's the difference between a Rev B ROM upgrade and the upgrade
> everyone wants Apple to provide to allow 128MB of RAM?
> 
The first Mac II ROMs had problems recognizing add-in 
memory boards.

This from the July 1991 issue of MacWorld pg. 178

Steve
-- 
Steve Graesser		{decwrl | amdcad}!megatest.uucp!sgrae
Megatest Corp.
880 Fox Lane
San Jose, CA 95131	|	(408) 441-3077

dittman@skitzo.csc.ti.com (Eric Dittman) (06/06/91)

In article <1991Jun4.191352.8623@eng.umd.edu>, tgoose@eng.umd.edu (Jason Garms) writes:
> For the record.  This was a free upgrade from Apple if you could show proof
> of purchase of a product that needed the new ROMs.

I got the upgrade without having to show proof of purchase.  This was about
18 months ago.
-- 
Eric Dittman
Texas Instruments - Component Test Facility
dittman@skitzo.csc.ti.com
dittman@skbat.csc.ti.com

Disclaimer:  I don't speak for Texas Instruments or the Component Test
             Facility.  I don't even speak for myself.

russotto@eng.umd.edu (Matthew T. Russotto) (06/06/91)

In article <676180918.0@blkcat.FidoNet> DON.NOLL@p3425.f421.n109.z1.FidoNet.Org (DON NOLL) writes:
>
>On of the things the REV B roms do is allow a NUBUS card to access more than 1 meg of ram each.  This helps you if you have a video board with gobs of memory or a NUBUS memory card for AUX.
> * Origin: Don's Point, Get it? (1:109/421.3425)

Doesn't matter for A/UX, if I remember correctly-- the manager is completely
rewritten within A/UX itself.

--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
     .sig under construction, like the rest of this campus.

mccabe@dopey.cs.unc.edu (ren) (06/07/91)

In article <1991Jun4.191352.8623@eng.umd.edu> tgoose@eng.umd.edu (Jason Garms) writes:
>The major feature that I know of is it allowed you to address more NU BUS
>cards with more than 1 MB of RAM.  Rev A ROMs wouldn't work with these cards.
>Jason Garms
>tgoose@eng.umd.edu

Do these ROMs also fix the boot problems when using 4 MB SIMMs (the special 
SIMMs for the Mac II with the PALs that fix test mode)????  If so, they could 
come in handy for Sys 7.0 (;-).

Thanx in advance,
danm

russotto@eng.umd.edu (Matthew T. Russotto) (06/07/91)

In article <4241@borg.cs.unc.edu> mccabe@dopey.cs.unc.edu (ren) writes:
>In article <1991Jun4.191352.8623@eng.umd.edu> tgoose@eng.umd.edu (Jason Garms) writes:
>>The major feature that I know of is it allowed you to address more NU BUS
>>cards with more than 1 MB of RAM.  Rev A ROMs wouldn't work with these cards.
>>Jason Garms
>>tgoose@eng.umd.edu
>
>Do these ROMs also fix the boot problems when using 4 MB SIMMs (the special 
>SIMMs for the Mac II with the PALs that fix test mode)????  If so, they could 
>come in handy for Sys 7.0 (;-).

No, for that you need the IIx (FDHD) Roms.

--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
     .sig under construction, like the rest of this campus.