> >Humm...  I had wondered why that was there.  Is there a way to detect VLB
> >devices some other way?
> This is specific to the aha2842 and is the only way I know of detecting
> those boards.

I thought that there was a tricky way, which involved doing
the EISA non-destructive card identification, and then throwing
out those things that hadn't registered themselves with the EISA
BIOS, but it's been a while since I looked at it.

My main concerns on this were:

1)      Not incorrectly identifying a VLBUS card as an EISA
        card; the code used to do this, way back when, on
        a per driver basis, by not using the EISA BIOS, and
        scanning for the EISA ID (which these cards had).

2)      Not blindly allocating the entire EISA space, which
        could conflict not only with VLBUS, but (at the time)
        some ENPIC assignments made by one of the PCMCIA
        bridge chipsets that were being used with VLBUS
        laptop video systems.

If I remember correctly, the was to fix this was to identify
the VLBUS card, both through the probe approach (which was not
destructive, as above, because it was only applied to SCSI
controllers after they were known to be there, and other VLBUS
cards were identifiable), AND through the EISA BIOS.  If a
card showed up in the first place, but not the second, then it
was a VLBUS card with an EISA table in it (I can't remember how,
but the EISA BIOS knew not to treat these as EISA cards).

This added an ugly third stage, so it went:

        VLBUS, EISA probe, AHA2842, EISA attach


                                        Terry Lambert
                                        [EMAIL PROTECTED]
Any opinions in this posting are my own and not those of my present
or previous employers.

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