Path: utzoo!attcan!uunet!mcsun!cernvax!chx400!ethz!visinfo
From: visinfo@ethz.UUCP (VISINFO c/o Sascha Schnapka)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: GVP A2000+8 + ST296N - How do you speed it up?
Keywords: GVP MaxTransfer SCSI
Message-ID: <4740@ethz.UUCP>
Date: 13 Jun 90 13:22:43 GMT
References: <4716@ethz.UUCP> <12552@cbmvax.commodore.com>
Reply-To: visinfo@bernina.ethz.ch.UUCP (VISINFO c/o Peter Simeon)
Organization: ETH Zuerich, Switzerland
Lines: 55

In article <12552@cbmvax.commodore.com> jesup@cbmvax (Randell Jesup) writes:

>>'hardblocks.h'. If you have entered all default values while installing the
>>drive with the GVP install script, you can find $00002000 in each part block
>>which is the maxtransfer. Change it to $00020000. Then write the block again
>>to your drive. The Rigid disk blocks also have a checksum, but you don't
>>have to correct it. I think GVP doesn't look at the checksum. It worked for
>>me without recalculating the checksum.
>
>	Ack!  It should check the checksum.  If you do this, you won't be
>able to read the rigiddiskblock from any RDB editor I know of, nor will
>you be able to drop it onto another controller without losing your
>partitioning information.
>
>	Doesn't GVP ship _some_ sort of RDB editor with their HD controller?
>Both Microbotics and Commodore do.

There are two completely different versions of the GVP scsidev.device which
are completely incompatible. The Version 1.0 is supplied with all GVP hard
cards and the Version 2.2 is supplied with SyQuest drives. Only the newer
version 2.2 are compatible with the RDSK standards used by Commodore,
Microbotics and others. This version also supports the SCSI direct access
with HD_SCSICMD (command 28). Unfortunately all GVP's without SyQuests are
delivered with the older 1.0 software and so nearly all people have the
old device. The 1.0 device has two big disadvantadges:

1. Rigid Disk Blocks are not fully compatible with the standard. They
   use C-strings instead of B-strings for the Device name.
   So you can't take your drive to another controller without some
   troubles.

2. SCSI direct access is not compatible with HD_SCSICMD.
   I had to write different versions of my HD-Tools for GVP 1.0.

I think they still deliver it, is because the version 1.0 is a bit faster
and the boot sequence is much faster. Note that the scsidev.device came
out before the RDSK standards were finished.
So don't use a RDB editor like HD-ToolBox or RdPrep! You can't use the
GVP RDB editor because they don't let you enter a maxtransfer > 8192.

At the AmiEXPO in Basel GVP has told me that they will soon release a new
scsi device which should be much faster. I hope all these problems will no
longer exist. I have told them about and they didn't know these problems.
May Be they think a Quantum with 300k/sec is fast enough.

>-- 
>Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
>{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.cbm.commodore.com  BIX: rjesup  
>Common phrase heard at Amiga Devcon '89: "It's in there!"

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