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- Newsgroups: comp.sys.apollo
- Path: sparky!uunet!nwnexus!lampi
- From: lampi@halcyon.com (Michael Lampi)
- Subject: Re: Adding Apollo disk as second disk in another Apollo ??
- Message-ID: <1993Jan23.175503.19507@nwnexus.WA.COM>
- Sender: sso@nwnexus.WA.COM (System Security Officer)
- Organization: Northwest Nexus Inc. (206) 455-3505
- References: <9301201629.AA28734@srvr1.engin.umich.edu>
- Date: Sat, 23 Jan 1993 17:55:03 GMT
- Lines: 50
-
- krowitz@QUAKE.MIT.EDU (David Krowitz) writes:
-
- >The WD7000 controller can handle two ESDI disk drives. Whether
- >or not they can be different types, I don't know. Assuming that
- >you can ...
-
- The WD7000 & DomainOS software can handle two different types of
- ESDI drives on the same controller. You *can* mix the Maxtor
- XT8760E and XT4380E drives. This does work.
-
- >The WD7000 controller has 3 disk connectors -- 1 control cable,
- >which is daisy-chained from the controller to drive 0, and then
- >from drive 0 to drive 1; and two data cables, which go directly
- >from the controller to each drive (or is it 1 data cable, and 2
- >control cables?).
-
- It is one daisy-chaining control cable and two separate (radial)
- data cables, one for each drive.
-
- >There are jumpers on the logic board of each
- >disk drive which sets them as unit 0 or unit 1. There is also
- >a set of terminators on the logic boards of the drives. Since both
- >of your drives came from systems which only had a single drive
- >apiece, both drives should have the terminators installed. When
- >you have two drives attached to a single controller, drive 0
- >should have the terminators removed, and drive 1 should have
- >them installed. I have seen a 2-drive system refuse to boot when
- >the 2nd drive (with the terminator pack) was detached from the
- >system.
-
- Depending on how you have the control cable wired, you may want to
- have the terminators left in place. For example, if you leave one
- disk drive in the system cabinet and have the other one outside,
- then it makes the most sense to daisy chain from the internal drive
- to the WD7000 controller to the outside drive. In this case it
- works better if the drives (one at each end of the control cable)
- have the terminators in place. This works quite well.
-
- >You can see the jumper selections and cable locations of both
- >the drives and the WD7000 controller by running the program
- >/systest/ssr_util/jumper and selecting the appropiate menus.
- >I know that the WD7000 will support two drive
- >s of the same type, it *might* support two drives of different
- >types. You'll have to just go ahead and try it.
-
- >== Dave Krowitz
- --
- Michael Lampi lampi@mdlcorp.com
- MDL Corporation 15301 NE 90th Street, Redmond, WA 98052
- (206) 861-6700 (206) 861-6767 FAX
-