Newsgroups: comp.sys.amiga.hardware
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!batcomputer!cornell!johnhlee
From: johnhlee@CS.Cornell.EDU (John H. Lee)
Subject: Re: A3000 and Syquest -- booting
Message-ID: <1991May14.221337.1726@cs.cornell.edu>
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Reply-To: johnhlee@cs.cornell.edu (John H. Lee)
Organization: Cornell Univ. CS Dept, Ithaca NY 14853
References: <21010.282c6b6a@oregon.uoregon.edu> <1991May13.115455@alamo.Berkeley.EDU> <21017.282eec91@oregon.uoregon.edu>
Distribution: usa
Date: Tue, 14 May 1991 22:13:37 GMT
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In article <21017.282eec91@oregon.uoregon.edu> gpotts@oregon.uoregon.edu writes:
>In article <1991May13.115455@alamo.Berkeley.EDU>, ipolyi@alamo.Berkeley.EDU (Harold H. Ipolyi 486-6444) writes:
>>In article <21010.282c6b6a@oregon.uoregon.edu>,
>>gpotts@oregon.uoregon.edu writes:
>>|> I have a new A3000 with a Syquest removable HD attached to the external
>>|> SCSI port. With the Syquest connected but powered down, the Amiga can't
>>|> find its internal HD to load Kickstart from -- I get the 2.0/1.3
>>|> requester screen with the HD buttons ghosted. With the Syquest connected
>>|> and powered up but no cartridge installed, I don't even get that screen;
>>|> the HD access lights on both the 3000 and the Syquest just pulse on and
>>|> off. Only if I have the Syquest powered up and a cartridge mounted (it
>>|> doesn't need to be an AmigaDOS formatted cartridge), will the Amiga boot
>>|> properly. Why is this and is there any way to fix it (other than unplugging
>>|> the Syquest)?
>>This is not a Syquest specific problem. I have a Syquest 44 and a Seagate 277
>>in an external box, and I also have to disconnect the cable when leaving
>>them
>>powered off. But it beats waiting for them to load up. I am currently only 
>>using them as backup devices, which serves my purpose.            Harold
>Well, this suonds to me like a serious shortcoming of the A3000's SCSI
>manager. The Mac's SCSI manager, for all its problems, can at least go
>out on the external buss, find what is there and powered up, mount what
>is flagged as mountable, and ignore the rest, so we know it can be done.
>Reaching behind the chassis to unplug the SCSI connector when I don't
>want to use the external devices is not an elegant solution. This is one
>of those things that makes a machine irritating to use. I hope this is
>addressed in a future version of the SCSI manager -- removable media are
>becoming more and more common.

SCSI devices usually cannot be left on the bus when powered off if they are
on the ends of the bus and have terminators installed.  Although the single-
ended 50-pin SCSI cable has a "Terminator Power" line, devices might power
their own terminators themselves, and Macintosh-style DB25 SCSI cables don't
have this power line at all.  Unpowered terminators pull down the entire
SCSI bus and causes everything to lock up.  This is not a A3000 controller
problem.

In my own setup, my tape drive sits in an external box.  Since I don't need
nor want the drive powered up all the time, the drive is unterminated.  The
terminators at the ends of the bus are elsewhere and have separate power.
I can leave the drive off and boot-up.  Later, I can turn the drive on,
mount BTNTape and start my backup.

I'm not sure why you can't boot with the Syquest powered up empty.  I'm
guessing, but it sounds like the SCSI driver is repeatedly polling the
Syquest and the Syquest is responding "not ready" instead of "no media
loaded."  The SCSI driver is waiting forever for the drive to spin-up.
I think you'll have to query Commodore Software Engineering for this one.


>On a related note -- is it possible to se a HD partition to SKIP with the
>HDToolbox? With my Supra SCSI controller I was able to set a partition to
>BOOT, MOUNT, or SKIP and thus create partitions that did not mount at boot
>time but that could be mounted later with the AmigaDOS "Mount" command. I
>found this useful for creating hidden partitions on a drive (AMAX partitions
>for example). With the HDToolbox, I only see a boot flag -- you either set
>a partition as bootable or not -- but no way to make a partition not auto-
>mount. Any solutions?

As documented in my A3000 manual, _Using The System Software_, under the
section for HDToolbox, set the partition's file system to "Reserved".  I
have my AMaxII partition set this way.  Under WB 2.0, the partition does
get mounted so that AMax can access it, but it doesn't show up on the WB
nor under Info--only as a mounted device in Assign.  It does show up on
1.3 WB, however.

You should be able to disable automounting for the partition using HDToolbox
as well.  I think it's under the Advanced Options in the Change Partition
window.

-------------------------------------------------------------------------------
The DiskDoctor threatens the crew!  Next time on AmigaDos: The Next Generation.
	John Lee		Internet: johnhlee@cs.cornell.edu
The above opinions are those of the user, and not of this machine.
