[comp.sys.apollo] Non-Apollo Disks on DN3500

butzer@CIS.OHIO-STATE.EDU (Dan Butzer) (08/08/90)

Thanks to everyone who replied to my request for info regarding 3rd party
disks on Apollo DN3500 (ESDI).  In su,,ary, I asked if it was possible to
connect 3rd party ESDI disks (ie HP97548E), and whether Apollo "locked
out" 3rd party disks, and if anyone had worked out a way to use 3rd
party ESDIs with Apollo DN3500's.   Based on the responses it is not
possible, and it is not due to "nasty marketing"  For details, read on...

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From: Timothy VanFosson <timv@cadfx.ccad.uiowa.edu>

My understanding is that they only recognize certain types of disk,
e.g., Maxtor XT8760E, because the controller only supports disks
of certain sizes and formats.  Any third-party disk that looks like
one of these supported types will work.  We are, in fact, using a
National Peripherals-packaged XT8760E on our DN3500 with no problems.

You may also want to check your DN3500 and see if it has a SCSI port.
If so, you should be able to add SCSI disks to your DN3500 without
problems.  I have not tried this but our FE says it should work.

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From: krowitz@richter.mit.edu (David Krowitz)

The DN3000, DN3500, DN4000, and DN4500 only use EDSI disks. Although
the Western Digitial WD7000 controller found in many of the more
recently shipped DN3500's and DN4500's has a SCSI port on it, the
disk controller portion of the board is an EDSI controller. The
Apollo OS only supports tape drives attached to the SCSI port of
the controller.

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From: krowitz@richter.mit.edu (David Krowitz)

Ah, well, that kind of negates my previous message ... Apollo's ESDI support
is written for a particular set of drives which they support. Try running
the program /systest/ssr_util/jumper to see which drives they support and
how the drives are jumpered (both on the controller board and on the disk
drive logic board). In addition, the CONFIG program (run from the mnemonic
debugger with the EX CONFIG command) lists the set of drives which Apollo
supports, but also (depending of the version) lists "other". I haven't
tried "other" before ... see what you can get with it.

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From: collins@nvpna1.prl.philips.nl (Donal O Coileain)

In comp.sys.apollo you write:
>I have heard from usually reliable sources that Apollo 
>likes to read MFG codes from disks, boards, etc, and lock out
>anything that they didn't sell.

HP-Apollo's DN2500 and HP9400 systems have SCSI busses so you are free to
attact multiple SCSI drives.

Outside of these two systems the choice is a bit limited.

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From: frank@caen.engin.umich.edu (Randy Frank)

this isn't Apollo marketing being nasty: the problem is purely technical.

Apollo uses a non-standard sector size (1280 bytes, I recall), which is
not a power of two.  Many ESDI disk drives don't support such non-standard
sector sizes.

As an amusing side note, one of the disks that won't work on the Apollos
are the HP OEM ESDI drives.  (Which is too bad, since they are supposed to
be one of the most reliable ESDI drives on the market.)  Maybe HP has a
motivation to fix this now!

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That's all folks.  Thanks Once Again.

--Dan