Well keep plugging away on it. Have you tried lower the negotiation
speed to the other devices (SCSI CDROM) on that bus. I am assuming the
CDROM is a narrow device (50 pin). Is it hooked up to the narrow
connector on the 2940?
How I have mine hooked up is:
1. CDROM hooked to the 50 pin IDC narrow connector with internal
termination on the CDROM.
2. 9ZX hooked up to the wide 69pin connector with an active terminator
on the end of the cable.
3. Automatic internal termination enabled on the 2940 (not always
suggested but works for me)
Here's my lame attempt at ASCII art
narrow wide
| |
CD-ROM v v Wide
internal----------- 2940 ============================= Active
termination || Terminator
IBM 9ZX
I am still confused as to if your drive is LVD is simple UltraWide. Do
you have the latest drivers?
-Eric
Charles Galpin wrote:
>
> thanks for the info. My knowledge of SCSI is truly limited, and I probably
> should not be going bleeding edge with my fist attempt (although SCSI 3
> should be out soon right :) )
>
> I have isolated this to just the contoller & drive and iether a SCSI CDROM
> or a NIC.
>
> Once all this is working though is to have an all SCSI system - drive(s),
> CDROM, CDRW, and probably a scanner at the very least. This is where I
> thought the U2W would be worth it. From the looks of things I probably
> should have gotten UW.
>
> Still not sure where this will end, but I hope it's soon.
>
> ===== Original Message from Eric Hegstrom <[EMAIL PROTECTED]> at
> 4/21/99 12:32 pm
> >No worries.
> >
> >You should still be able to set the BIOS to negotiate with the drive up
> >to it's maximum interface speed. I missed the original posts of this
> >message, but is it true that this is an LVD interface (80 MB/sec). I
> >was just saying that you won't actually be able to copy data to the
> >drive at that sustained throughput. I have no experience with the LVD
> >drives. I just wanted to say that I haven't any problems with the 9ZX -
> >I would personally recommend it. And for what it is worth I am using the
> >ASUS P2BS motherboard with the onboard AIC-7890 UW/LVD controller.
> >Previous to the RedHat 5.2 release it was kind of flacky. Are you using
> >the latest build of the driver? I had trouble getting everything patched
> >corectly so I just went out and bought the 5.2 Redhat and it installed
> >correctly. I have the 9ZX in a removable drawer and I take it home and
> >use it on a machine with the 2940UW card at home. I even have internal
> >automatic termination set on the that unit (which I guess is asking for
> >trouble).
> >
> >Personally I have been avoiding the LVD drive interfaces. The UW2 is
> >fast enough for me (since I usually only have 1 drive, and at most 2, on
> >the bus). It is a common mistake to confuse interface speed with
> >sustained throughput of the drive. The interface transfer rateis the
> >maximum transfer rate that the controller can negotiate with the drive
> >(80MB/sec LVD, 40MB/sec UW2), and the sustained throughput of the device
> >is limited by the media transfer rate (how fast the data can be
> >physically written to the drive). With multiple devices on the bus
> >having high interface transfer rates is great when it works 'cause you
> >can service the SCSI targets that much faster. With just one SCSI target
> >it is a wash. I am by no means an expert on this. I assume you have
> >tried this drive alone.
> >
> >-Eric
> >
> >Charles Galpin wrote:
> >>
> >> please excuse my ignorance, but this is my first experience with SCSI...
> >>
> >> ===== Original Message from Eric Hegstrom <[EMAIL PROTECTED]> at
> >> 4/21/99 10:47 am
> >> >Well lloking at that URL, I see thatthe Maximum Interface transfer rate is 80
> >> >MB / sec, but the Media transfer rate 108.6 to 171.1 Mbits / sec which is
> >> >13.575 - 21.3875 MB/sec.
> >>
> >> Ok, what is the net result? that I can only expect 13.575 - 21.3875 MB/sec
> >> and to set the BIOS accordingly? I tried 13.5 and 10 MB without luck, and
> >> would say that for this speed perhaps this U2W controller/drive is not worth
> >> it!
> >>
> >> >
> >> >I have the 10200 RPM wide version of this drive (the IBM Ultrastar 9ZX I
> >> >beleive) and I have 2 systems (one with an internal AIC-7890 Adaptec UW/LVD,
> >> >the other with a 2940UW). The drive works great in both systems. I am able to
> >> >get almost 18MB/sec sustained transfer rate for streaming. I remember just a
> >> >few years ago when we needed to buy $8K RAID arrays at work to get 12MB+/sec.
> >>
> >> is this one of those integrated into an P2Bs? I considered going that route,
> >> but figured it ould be better to have a seperate adapter and get a less
> >> expensive AMD cpu now, and later upgrade if I want.
> >>
> >> >Oh yea, I am using the Redhat 5.2 install (I think it is kernel 2.0.32 but I am
> >> >not sure)
> >> >
> >> >Peace,
> >> >Eric
> >>
> >> -- Charles Galpin <[EMAIL PROTECTED]>
> >
> >--
> >Eric Hegstrom .~.
> >Senior Software Engineer /V\
> >Sonoran Scanners, Inc. // \\ L I N U X
> >[EMAIL PROTECTED] /( )\ >don't fear the penguin<
> >520-617-0072 x402 ^^-^^
>
> -- Charles Galpin <[EMAIL PROTECTED]>
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to [EMAIL PROTECTED]
--
Eric Hegstrom .~.
Senior Software Engineer /V\
Sonoran Scanners, Inc. // \\ L I N U X
[EMAIL PROTECTED] /( )\ >don't fear the penguin<
520-617-0072 x402 ^^-^^
-
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to [EMAIL PROTECTED]
