Path: utzoo!utgpu!news-server.csri.toronto.edu!ois.db.toronto.edu!tron
Newsgroups: comp.unix.sysv386
From: tron@db.toronto.edu ("Carlos G. Mendioroz")
Subject: Re: Help on tape drive interoperability/reliability
Message-ID: <90Nov20.082559est.343@ois.db.toronto.edu>
Organization: Department of Computer Science, University of Toronto
References: <53180005@hpindda.cup.hp.com> <1990Nov20.000121.23207@ico.isc.com> <1712@chinacat.Unicom.COM>
Date: 20 Nov 90 13:26:43 GMT
Lines: 24

chip@chinacat.Unicom.COM (Chip Rosenthal) writes:

>In article <1990Nov20.000121.23207@ico.isc.com>
>	rcd@ico.isc.com (Dick Dunn) writes:
>>rajs@hpindda.cup.hp.com (Rajeev Seth) writes:
>>> Everex tech support told me that it is not good enough that two different
>>> tape drives/machines read/write QIC-24 because the controller card for the
>>> drive has some security PAL chip [...]
>>Not only do we not find it to be true with other brand drives; I barely
>>find it believable.

>Of course not.  If they did that, it wouldn't be QIC-24 anymore!

>I think the confusion might be that Bell Tech used to OEM somebody's tape
>controller card (Everex?) and there was a PAL which prevented the adapters
>and drives from being interchanged.

And if they did that, it would't be QIC-02 anymore...

I think that the PAL's referred are those locating the control regs
of the controller. That way a driver for one card can't be used with
another card. E.G. wangtek PC-36 controllers have two control regs
one at adddress X (selectable) and the other at X+1.
Some dealers change PAL's to bring that to X+2...