[Doug Ledford]

philipp scherer wrote:
> 
> > This is almost guaranteed to cause problems.  First, I'm not sure, but I
> > wouldn't be the least bit suprised if termination were always enabled for the
> > 50 pin interface, even when set to auto.  That would over terminate the bus.
> > Second, I wouldn't be suprised if your total cable length exceeds the 1.5m
> > maximum cable length.  Third, the typical 25 pin connector on the zip drives
> > and the zip drive cables interfere with the transmission wave properties of a
> > SE SCSI bus, so that can cause additional errors on faster devices (the zip
> > drives don't care because they only run in async mode, but they went so cheap
> > on construction that you almost can't put a zip drive on the same SCSI bus as
> > anything else, which pisses me off, especially if you are anywhere near your
> > cable length limits and any other device wants to run in sync mode).
> >
> >
> 
> You are definitely right.  The external cable to the zip was 1m  and  the
> internal
> ribbon about 1m with the  connection to the scsi controller somewhere in the
> middle. Without the external connection the scsi problems disappeared and the
> plextor CDROM makes synchronous transfers at 20MB/s. So I will get an
> internal ATAPI zip and leave the SCSI zip with my old P90 system where it
> makes no problems.  But I am still curious about the old driver. Did it work
> without problems due to the smaller initial transfer rate ?

That and the fact that I fixed some termination bugs that would have helped in
your particular case.

-- 

 Doug Ledford <dledford at redhat.com>  http://people.redhat.com/dledford
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