Subject: Re: help with A3000
To: None <amiga-dev@sun-lamp.cs.berkeley.edu>
From: Michael L. Hitch <osymh@gemini.oscs.montana.edu>
List: amiga-dev
Date: 05/24/1994 18:58:06
On May 24,  2:36pm, Donn Cave wrote:
> I have been meaning to look at st anyway, because it locks the system while
> doing tape motion, which probably isn't the desired effect.  For example,
> type "mt -f /dev/nrst0 fsf 1".  The SCSI LED goes on and stays on, the
> keyboard is 99% disabled, mouse disabled, etc.  (I can get a few characters
> through to the keyboard, to show on the screen after the tape's through,
> but most of them are just dropped.)  The drive is an Exabyte 8200; no
> problem with BTNtape.

  It locks the system because none of the scsi drivers implement
disconnect/reconnect.  Nothing else can be done on the scsi bus until
the current operation completes.

  Keyboard characters shouldn't be lost though.  Oops, I just thought
of something - I mentioned this to Chris Hopps when I saw it and didn't
think that what he was doing was correct.  The 33C93 driver (A3000, A2091,
and GVP Series II) always uses the polled I/O when doing a non-data
transfer.  The driver is probably called at the slpbio() level, which
is going to block the keyboard interrupts.  I didn't do that with the
53C710 driver, so I don't see that problem.

Michael

-- 
Michael L. Hitch			INTERNET:  osymh@montana.edu
Computer Consultant			BITNET:  OSYMH@MTSUNIX1.BITNET
Office of Systems and Computing Services
Montana State University	Bozeman, MT	USA

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