SCSI controller problems

[Jeff Vian]

On Sun, 2004-07-11 at 16:18, Stewart Nelson wrote:
> Hi,
> 
> I have a new Fedora installation, and have no access to my
> SCSI DAT drive, nor to a SCSI DVD-RAM drive.
> 
> I tried two different controllers:
> 
> The ASUS PCI-SC200 board, based on the Symbios 53C810 chip,
> is listed by Hardware Browser under Unknown Devices.
> No connected SCSI devices appear.
> 
> dmesg shows:
> 
> PCI: fixing NCR 53C810 class code for 03:0c.0
> ...
> sym53c8xx: at PCI bus 3, device 12, function 0
> sym53c8xx: not initializing, device not supported
> ...
> sym53c8xx: at PCI bus 3, device 12, function 0
> sym53c8xx: not initializing, device not supported
> 
> 
> 
> The Kouwell KW-801V75, based on the Symbios 53C875 chip,
> is listed properly under SCSI Devices with driver sym53c8xx .
> The devices appear correctly under Tape Drives (/dev/st0) and
> CD-ROM Drives (/dev/scd1).  But when I try to access them
> with mt or mount, I get a 'No such device or address' error.
> 
> dmesg (with just the DAT drive connected to the SCSI bus, but
> the DVD-RAM connected via IDE, see below) shows:
> 
> sym53c8xx: at PCI bus 3, device 12, function 0
> sym53c8xx: setting PCI_COMMAND_PARITY...(fix-up)
> sym53c8xx: 53c875 detected with Symbios NVRAM
> sym53c875-0: rev 0x26 on pci bus 3 device 12 function 0 irq 5
> sym53c875-0: Symbios format NVRAM, ID 7, Fast-20, Parity Checking
> sym53c875-0: on-chip RAM at 0xfeafd000
> sym53c875-0: restart (scsi reset).
> sym53c875-0: Downloading SCSI SCRIPTS.
> scsi1 : sym53c8xx-1.7.3c-20010512
> blk: queue dc299c18, I/O limit 4095Mb (mask 0xffffffff)
>   Vendor: SONY      Model: SDT-7000          Rev: T306
>   Type:   Sequential-Access                  ANSI SCSI revision: 02
> blk: queue dc299a18, I/O limit 4095Mb (mask 0xffffffff)
> Attached scsi CD-ROM sr0 at scsi0, channel 0, id 0, lun 0
> sr0: scsi3-mmc drive: 32x/32x writer dvd-ram cd/rw xa/form2 cdda tray
> st: Version 20030406, bufsize 32768, max init. bufs 4, s/g segs 16
> Attached scsi tape st0 at scsi1, channel 0, id 0, lun 0
> sym53c875-0-<0,*>: FAST-10 SCSI 10.0 MB/s (100.0 ns, offset 15)
> sym53c875-0: detaching ...
> sym53c875-0: resetting chip
> scsi : 1 host left.
> 
> 
Have you checked the scsi ID on both devices??  If they are the same it
WILL NOT work.

>From your output above it seems both devices are scsi attached and both
are set at ID 0. What it tells me is the bus is probed, sees the adapter
at ID 7, the cdrom as sr0 at id 0, the tape as st0 at id 0, then removes
both the cdrom and tape because they conflict.  It then detaches and
resets the controller.

You cannot make a scsi bus work with 2 devices at the same ID. You may
see one, both, or none, but even if seen they will not work.

The adapter is set at ID 7, so one of the tape or cdrom may be at 0, but
the other *must* be at some other address.  ID 1 would be good.

Try resetting one of them to a different id and it should work.

Good luck
Jeff