[3014] in linux-scsi channel archive
Re: adaptec and zip drive
daemon@ATHENA.MIT.EDU (Leonard N. Zubkoff)
Tue Dec 30 16:11:04 1997
Date: Tue, 30 Dec 1997 12:26:26 -0800
From: "Leonard N. Zubkoff" <lnz@dandelion.com>
To: dnw@eskimo.com
CC: linux-scsi@vger.rutgers.edu
In-reply-to: <Pine.LNX.3.91.971229141332.682A-100000@localhost> (message from
Dave Williams on Mon, 29 Dec 1997 14:17:10 -0800 (PST))
Date: Mon, 29 Dec 1997 14:17:10 -0800 (PST)
From: Dave Williams <dnw@eskimo.com>
I have spent the last several weeks in sporadic attempts to get my Iomega
zip drive to work with my Adaptec 1542c adapter.
ASUS TX97 motherboard, Pentium 166, Maxtor and Fujitsu disks connected to
the internal cable. Kernel 2.0.32, no modules (I had some problems with
modules, not germane here.)
With the zip on a short external cable, linux will boot all the way to
just before the prompt; then I start getting "Sent reset..." and timeout
messages, and reset is the only way out.
After a long email conversation with Adaptec support (I send an email;
they respond a week later...), I got to the point where if I boot DOS
from floppy, everything works: I can read, write, copy and delete large
files to/from the zip drive. Is this just because DOS is so stupid it
can only do one thing at a time and therefore doesn't confuse the bus? (I
haven't left the machine running for long periods of time with DOS booted:
after all, I want to _use_ it, not just listen to the drive spin.)
Most likely.
Of course, this means that everything's hunky-dory as far as Adaptec is
concerned: "We don't support linux." I thought that I was going to be
able to tell them the thing wouldn't work under DOS either....
Anyway, I still want to get the drive to work: backing things up in 100
meg chunks with random access fits in too nicely with my particular needs
to give up.
I am considering a couple of options: get the Iomega SCSI adapter and try
to make it coexist with the Adaptec. Has anyone tried this/made it work?
Get rid of the Adaptec in favor of another adapter: BusLogic seems to
be the way to go, from what I've read. Has anyone done _this_?
Does anyone have another suggestion?
If I recall correctly, ZIP drives do not have a proper SCSI connector at all,
but rather use a DB25 which doesn't provide for adequate signal integrity.
It's quite likely that this configuration won't work any better on a BusLogic
than the Adaptec, though the BusLogic driver is more likely to recover without
crashing that the 1542 driver. Your best bet is a separate SCSI host adapter
for the ZIP. Since an Adaptec 1542C is pretty much a guaranteed performance
bottleneck for a fast PCI system, you might want to consider getting a good PCI
SCSI host adapter and using the 1542C for the ZIP if the two will work together
when it's the only device on the 1542C.
Leonard
