Old school computer

kuun · Post by **kuun** » Wed May 28, 2003 4:20 pm

what is being used as the main drive? the drive with the OS?

hyperspace · Post by **hyperspace** » Wed May 28, 2003 9:06 pm

You may have to try each drive seperately to determine which drive(s) are working. Set each drive to 0 when you try them and make sure termination is set properly. You may want to record the SCSI number of each drive before you test rhe drives.

kuun · Post by **kuun** » Wed May 28, 2003 9:23 pm

you do not need termination for 1 or 2 scsi drives

hyperspace · Post by **hyperspace** » Thu May 29, 2003 10:33 am

kuun wrote:you do not need termination for 1 or 2 scsi drives

R U sure about that?

kuun · Post by **kuun** » Thu May 29, 2003 3:12 pm

hyperspace

i used 2 SCSI drives for the longest time without termination

neither of the drives (old 1GB IBM 50 pin SCSI drives) had termination, and i didn't have termination

when i got my 3rd drive, then i had to weorry about termination

and even now, i only have the end of the chain terminated, the beginning isn't terminated

trust me

hyperspace · Post by **hyperspace** » Thu May 29, 2003 6:53 pm

Interesting. Maybe the drives and SCSI card were set for AutoTerminate.

I dunno. I was always under the impression there was always two termination points. One at the SCSI card and one at the last drive. One can terminate the end of the SCSI cable.

Hmmm...

I'll have to do a little research. From:

http://www.scsita.org/aboutscsi/SCSI_Te ... orial.html
...

Where do you terminate the bus?

[Terminate: from the latin terminus meaning "the end".]

Termination must be present at two and only two positions on the SCSI bus, at the beginning of the bus, and at the end, and must occur within 4 inches of the physical ends of the SCSI bus. Often, the host will be installed at one end of the bus, and will provide one of the two terminations required.

When do you terminate the bus?

Always. Period. Whenever you want the SCSI bus to operate reliably!

...

kuun · Post by **kuun** » Thu May 29, 2003 7:00 pm

no

you don't have to have termination for 1 or 2 drives, thats almost like having another IDE port

and thats 2 devices per channel

jsut like IDE

hyperspace · Post by **hyperspace** » Thu May 29, 2003 7:04 pm

Did your SCSI card or SCSI drives have autotermination?

hyperspace · Post by **hyperspace** » Thu May 29, 2003 7:12 pm

kuun · Post by **kuun** » Thu May 29, 2003 7:16 pm

no they did not

and they worked fine until i got stupoid and send voltage back through the SCSI bus attempting to terminate it

i don't care what that says, i had 2 SCSI drives running non-terminated

if you like i can find specs for the drive so you can see there was no termination at all

hyperspace · Post by **hyperspace** » Thu May 29, 2003 7:22 pm

No temination at all!?

Yeah, if you have some time, I would be interested. Thanx.

kuun · Post by **kuun** » Thu May 29, 2003 7:41 pm

no when i only had 2 drives i had absolutely no termination

now i only have the end drive terminated, only becasue it has ondrive termination

kuun · Post by **kuun** » Thu May 29, 2003 8:01 pm

ok the only one of the old 2 drives is a IBM 0663L12 SCSI 50 pin scsi

http://www.fos.su.se/~stefan/rs6000/sd1gb.htm

it's hard to find anything on these anymore

http://www.hgst.com/hdd/support/0663x/0663xjum.htm

aha! found soemthing

if you will notice on the jumper specs screen, there is nothing for termination

hope this helps

kuun · Post by **kuun** » Thu May 29, 2003 8:03 pm

here are the complete specifications

http://www.hgst.com/hdd/support/0663x/0663xdes.htm

hyperspace · Post by **hyperspace** » Thu May 29, 2003 8:20 pm

1 GIG Drives? I wonder if the SCSI spec for the drive is before termination was part of the today's spec.

hyperspace · Post by **hyperspace** » Thu May 29, 2003 8:25 pm

Are these removeable drives?

kuun · Post by **kuun** » Thu May 29, 2003 8:45 pm

yes they are 1GB drives

and no they are not removeable

hyperspace · Post by **hyperspace** » Fri May 30, 2003 7:39 pm

The drives might not be dead. The backplane could be defective.