SCSI HP ScanJet termination question

[Bruce Morgen]

Does anyone know anything
about the termination
circuits of SCSI ScanJets
from back in the '90s?
Mine is working fine in a
chain with my internal
CD-R and DVD drives, but
I wonder if (a) I'm just
getting away with running
unterminated and (b) if I
can chain another external
SCSI device after the
scanner. I have no manual
for the scanner, so I'd
appreciate any knowledge
available on this issue.
Thanks in advance!




.................................................................
Posted via TITANnews - Uncensored Newsgroups Access-=Every Newsgroup - Anonymous, UNCENSORED, BROADBAND Downloads=-

 

[David]

Does anyone know anything
about the termination
circuits of SCSI ScanJets
from back in the '90s?
Mine is working fine in a
chain with my internal
CD-R and DVD drives, but
I wonder if (a) I'm just
getting away with running
unterminated and (b) if I
can chain another external
SCSI device after the
scanner. I have no manual
for the scanner, so I'd
appreciate any knowledge
available on this issue.
Thanks in advance!

If it is a 5P, it should function as the final device without external
termination, providing you connect via the right hand connector, as viewed
from the *back* of the device.



Cheers

 

[PeterD]

Does anyone know anything
about the termination
circuits of SCSI ScanJets
from back in the '90s?

A post not surprisingly short on facts and details. What model
scanner? What interface card? Give some details, and facts, not a
vague "the 90's" words. There were many HP scanners in that time
period.

 

[Bruce Morgen]

A post not surprisingly short on facts and details. What model
scanner? What interface card? Give some details, and facts, not a
vague "the 90's" words. There were many HP scanners in that time
period.

For the record, the SCSI
channel is a built-in, on-
motherboard Adaptec AIC-7880
with termination set to
"auto." The scanners are a
ScanJet IIp and a ScanJet
IIc -- both have the typical
HP SCSI connections of that
time: a DB-25 (which is what
I'm now using) and a big,
old-fashioned female
Centronics receptacle like a
parallel printer has.




.................................................................
Posted via TITANnews - Uncensored Newsgroups Access-=Every Newsgroup - Anonymous, UNCENSORED, BROADBAND Downloads=-

 

[Bruce Morgen]

Bruce Morgen wrote:

Does anyone know anything
about the termination
circuits of SCSI ScanJets
from back in the '90s?

[snip]

If it is a 5P, it should function as the final device without external
termination, providing you connect via the right hand connector, as viewed
from the *back* of the device.

OTOH, if it's an old ScanJet II, it has both Centronics and DB25 connectors
on the rear panel. There aren't any internal terminators; if it's at the
end of the SCSI chain you need to either install a pass-through terminator
between the cable and the connector, or put a terminator on the connector
not occupied by the cable.

[snip]

Thanks Joe -- I'll plug
a terminator into the
(currently unused)
Centronics connector,
no problem doing that.
Help much appreciated!



.................................................................
Posted via TITANnews - Uncensored Newsgroups Access-=Every Newsgroup - Anonymous, UNCENSORED, BROADBAND Downloads=-

 

[PeterD]

For the record, the SCSI
channel is a built-in, on-
motherboard Adaptec AIC-7880
with termination set to
"auto." The scanners are a
ScanJet IIp and a ScanJet
IIc -- both have the typical
HP SCSI connections of that
time: a DB-25 (which is what
I'm now using) and a big,
old-fashioned female
Centronics receptacle like a
parallel printer has.

The Scanjet IIc I know (and use frequently) it does not have any
termination built in, if it is the end of the string then one
connector goes to the bus, the other put a terminator on. That 'big
fat' connector was (at the time) the standard for SCSI, but there are
adapters avaialble to convert it to the more commonly used connectors
of today. BTW, and IMHO, the IIc was a great scanner. I use it
frequently as a photocopier (I have the ADF which makes it
worthwhile), and do some reasonable scans with it too.

The scaning software from HP for the IIc is a bit awkward, and takes
practice to get a good scan, but once you figure it out, you can get
reasonable resolution and quality.