🚀 go-pugleaf

In <10667@cbmvax.commodore.com>, mks@cbmvax.commodore.com (Michael Sinz - CATS) writes:
>In article <PASSARET.90Apr5112459@brahe.crd.ge.com> <passaretti@crd.ge.com> writes:
>>
>>Ok,  I'm about to get a 500/590 for hacking on (Cheapest
>>alternative 'till the 3000 comes out, then a good X
>>terminal).  My housemate has a 1000/590 and we'd like to
>>share SCSI devices.  Is this possible??  Is it feasible??
>
>Is it possible?  Well...  You need a new device driver, modify one of the
>590s to be at a different SCSI ID, and write some from of arbitration.
>(The best bet would be to have one of the devices act like a drive to
>the other and then have that one control the disk.  This makes it like a
>server/client.  Sharing the drive otherwise comes into the problem of who
>has the right to read/write/cache any part of it.)

I am currently awaiting delivery of a 2091, so this and a couple of other
comments about the 2091 are of interest to me.

I agree that the best bet would be, as you say, to write some form of
arbitration making one host adapter look like a disk, but I am wondering if the
2091 supports SCSI bus arbitration (lower level than the arbitration you are
speaking of), so that, for example, an IO device could act as a master on the
bus.

Disconnect/reconnect... I noticed a posting from Dave Haynie that mentioned the
2091 disconnecting between the command and data phases in case something else
needs to use the bus. Is this 'generic' disconnect/reconnect capability? It
would be real nice if it is, so I could keep the tape streaming without having
to go to a separate tape controller. If it has this capability, can it be
turned on/off on a physical device basis for those devices that do not support
the capability?

-larry

--
Entomology bugs me.
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|   //   Larry Phillips                                                 |
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