[comp.periphs.scsi] SCSI Dat drive ejects on device close

mah@wu-wien.ac.at (Michael Haberler) (05/28/91)

I hooked up a HP35450A DAT tape to Xenix 2.3.2GT with an Adaptec 1542B
controller. [hint: doesnt work with Rev.B HP firmware, must be Rev C].

This works, except that on every device close, the tape gets *ejected*
from the drive. Needless to say, this doesnt make it too useful in 
a unattended-backup situation.

I've permuted a few Xenix patches, to no avail.

Any clues/minor number magic/kernel patches? 

- michael

pls cc me at mah@wu-wien.ac.at. Thanks.

ps: [Roy Neese: I tried mailing to you as neese%adaptex.uucp@uunet.uu.net,
     is this wrong? -tnx, michael]
-- 
Michael Haberler 		mah@wu-wien.ac.at,  mah@awiwuw11.bitnet
University of Economics and Business Administration
A-1090 Vienna, Augasse 2-6	    Biz:    +43 (1) 31336 x4796 Fax: 347-555
Home: +43 (1) 961-679 (voice & fax) D-Netz: +43 (663) 811-056

kev@hpcpbla.HP.COM (Kevin Jones) (05/30/91)

Sounds like the Xenix driver is sending a SCSI "UNLOAD" command on
a device close. This will cause the tape to eject.

This is standard behaviour on HP DAT drives (+ a number of other
manufacturers DAT drives).

There are 2 ways the driver could avoid the unwanted tape eject:
1. Don't send an UNLOAD command, it's not neccesary.
2. Send a SCSI "PREVENT MEDIUM REMOVAL" command prior to sending the
   UNLOAD. The UNLOAD will no longer cause the drive to eject tape.
   (This also disables the eject button)


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