27 Sep
2006
27 Sep
'06
3:55 p.m.
Roger Merchberger wrote:
Ah, no. The latest transfer rate is Ultra 320 - it's been out for at least
a few years now.
I think the 80 pin SCA is only a matter of the hot
plug
spec and connector, and can be dealt with by adapters
from the 50 pin or 68 pin cables to the SCA back
plane connectors. It also deals with the device address
in the connector.
Although there are 50-pin to 80-pin adapters, remember that 50-pin is only
an 8-bit-wide bus and so your throughput would not be any faster than with
an 8-bit-wide device (of the same bandwidth).
Hope this helps,
Roger "Merch" Merchberger
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Billy:
I first started working on Ultra 320 at Quantum in 1999; but they never
shipped a product until 2001. 160 wasn't a clean intro - lots of
controller/system problems. Don't know how 320 was on initial release, but
given the same cast of characters, it might have been rough too.
SCA 80 pin has a lot of adaptors to go to/from 68 pin. I even have an old
Apple system using an SCA drive on a 50 pin bus via an adaptor PCB. If
using SCA, key point to remember is that power is inside the 80 pin
connector. SCA drives don't normally have the legacy 4 pin Molex power
connector.
And I'm surprised that nobody has mentioned the early Apple SCSI, that was
25 pin. I'm still using some 50 to 25 pin cables on my G4 to drive some old
Epsom scanners. And even have one scanner on an Initio wide controller
doing a double conversion, 68 pin to 50 pin, then a 50 pin to 25 pin cable!
SCSI is FUN! - Old lapel pin I picked up at some Comdex.
Billy