On the seventh day, Brcobrem wrote...
> Well, it failed on me again via the USB connection (for the hundredth
> time). So I'm going to go with Christian's suggestion and go Scsi.
:-(
> For those who may be interested, my motherboard has a scsi chip on it
> that provides a 50 pin Scsi1 connector, a 68 pin Scsi2 connector, and a
> 68 pin Ultra Scsi2 connector. The motherboard-to-backplate adapter that
> came with the motherboard is 68 pin. So how to go from 68 pin female on
> the backplate to that 50pin miniture female on the HP Scanjet 6200C ? I
> spoke to cablestogo.com and they recommended their "SCSI external
> cable - HD-68 (M) - HD-50 (M) - 6 ft", P/N 08177.
Don't (repeat: don't!) do it this way if you can prevent it! Assuming the
68pin backplate connector is used to connect to the Ultra Wide 2 SCSI part
of your controller (which is almost certain since I haven't heard of
anything else), this will not only decrease the allowed cable length for
LVD scsi (also called Ultra Wide 2 SCSI, used in U160 and U320 too), it
will limit the number of devices possible and finally decrease speed for
all LVD devices. You can also get into all kinds of trouble.
> The HP Specs do not mention the Scsi spec that the scannner allows, so
> I'm only hoping that since it has the 50pin miniture Scsi2 connector,
> that the scanner will provide the throughput of the Scsi2 specification
> (10MB per sec).
that's right, that's Fast SCSI 2.
> Fyi:
> Connector Type or Name: HD50 High Density 50-Pin
> Called Mini D50, MicroDB50, MiniDB50, most 8-Bit SCSI FAST (up to
> 10MB/sec) host adapters use this "high density 50-pin" connector.
> 50-pin HD50 connector is 1 3/8" (36mm) wide vs. 1 7/8" (47mm) wide for
> a 68-pin HD68 connector. Used on SCSI-2 and SCSI-3 peripherals.
the better way to do it is to get an internal cable with 50pin-50pin
connectors (so-called HDC50). You'd better think twice if you might need
some internal connectors for devices like streamer and so on in the future
(however, such devices are getting pretty scarce nowadays, most come with
68pin connectors for wide ultra/single-ended or wide ultra 2 (LVD)).
But be careful: the cable length for that bus mustn't exceed 3m in total,
that means you have to count the cable for the scanner as well.
The second part you need is a 50pin to 50pin Sub-HD (HDC50 to HD50) slot
bezel (you lose one PCI/ISA slot). The external cable you need has two HD50
connectors. Check for the cable thickness - usually such cables need to be
pretty thick for quality otherwise they are known to cause problems. AFAIK
the scanner doesn't need to be terminated (might have auto-termination,
mine is running flawlessly). Should you ever get some internal devices, you
mustn't terminate them. Be also careful to not Y-connect the bus (meaning
that you must connect the adaptor to the end of the internal cable).
Interesting reading:
http://www.ramelectronics.net/html/scsi_connecters.html
HTH
--
mit freundlichen Grüßen/with kind regards
Christian Dürrhauer, Institute of Geography, FU Berlin
Little Golden Book That Never Made It: Dad's New Wife Robert