Subject: Re: ncr driver working well with 53c875?
To: Marc Slemko <marcs@znep.com>
From: Stefan Esser <se@freebsd.org>
List: current-users
Date: 05/27/1997 13:06:51
On May 26, Marc Slemko <marcs@znep.com> wrote:
> I have run both a DC-390U (ultra) and a DC-390F (ultra wide) under FreeBSD
> without any real problems.  The U isn't wide, but still uses the 875
> chipset. 
> 
> Note that the Tekram's BIOS doesn't like disks partitioned using FreeBSD's
> dedicated mode and will hang on boot if it sees one.  

Well, it will write a nasty complaint, and will pause for
some 10 seconds, but will eventually continue the SCSI bus
scan ...

> The only problem I had was when attaching a wide drive to the narrow
> controller (390U) , the code kept thinking it could talk over a wide bus
> (the chip on the contoller is a 875, which is wide, the drive is wide, but
> the connection is narrow) and blew up horribly.  To work around this I
> just used the appropriate define to force the NCR driver to only talk
> narrow. 

There is not much that can be done about the problem of 
WIDE drives connected to a WIDE host adapter with an 8bit
SCSI cable. The driver should fall back to non-WIDE mode
if WIDE transfers fail because of the cable, but I have 
never tested that feature.

One more point for the ToDo list ... :)

Regards, STefan