Re: Stray ROM chip -what is it for?

[mjmahon@aol.com (Michael J. Mahon)]

Ernest replied:

>"Michael J. Mahon" <mjmahon@aol.com> wrote in message
>20030810214531.20867.00000426@mb-m24.aol.com">news:20030810214531.20867.00000426@mb-m24.aol.com...
>> Ernest asked:
>>
>> >I found a stray ROM chip labeled APPLESUR Ver. 3.1. Does anyone know what
>it
>> >might be for?  It's a 2732 chip.
>>
>> Sounds like the ROM for an Applesurance diagnostic disk controller.
>> This was a disk controller that performed diagnostics on the machine
>> prior to booting up.
>>
>> Maybe the original owner swapped it out for Ver. 3.2.  ;-)
>
>Interesting. I wonder if they were using it in a Basis Diagnostic disk
>controller? I've never seen an Applesurance card but a ROM from one ended up
>in a box of Basis 108 junk. There's also a Micro-SCI controller card with
>some sort of utility ROM in it but I think it's broken.

The Applesurance controller's disk control function was compatible
with all Apple-compatible slots, like the Basis 108, but its diagnostic
functions may have depended specifically on the Apple ROMs
(e.g.: a ROM checksum).

Basis could easily have made a deal with the manufacturer to
produce a Basis-specific model (the pre-boot diagnostic would
be very Basis-like  ;-), but if that were the case, I would expect
it to be marked accordingly, so maybe it "just works" in the Basis.

-michael

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