carl0s wrote:
You make a new ribbon cable with an extra connector of course ! Easy.
Graham
I don't think it is as easy as that.
The 68-pin connector on the rear panel is almost certainly mounted on the
motherboard, with no cable.
The other channel, which feeds the SCSI backplane for the two 80 pin SCA
drives would need more than 68 pins, so will not be 68-pins.
I can't switch the machine off now to look and its impossible to remove
the side panel without it tripping a micro switch that disables the ouput
form the power supply.
As such, I don't believe there are any internal 68-pin SCSI connectors.
Someone else hit this problem in a Sun Blade 2000 computer.
http://groups.google.co.uk/group/com...4c eff3c244ee
which is a somewhat similar. Mine is somewhat older, but quad processors,
whilst that is somewhat never and dual processors.
It would appear from the replies he got that for DDS-4, you can use a
narrow connector (50 pin), as the data is only transfered at about 5 MB/s
maximum.
I'm still confused. You can buy SCA to 68-pin adapters, and 68pin to 50-pin
adapters. The big problem would be that the bus would run at the speed of
the slowest device.
The SCSI path is:
motherboard ------SCA backplane ----CD-ROM and terminator.
The cable between the motherboard and the SCA backplane does not have
nice simple 68-pin cables with standard connectors.
The cable between the SCA backplane and the terminator (which is part of
the cable) is possibly 68-conductors, but has no standard 68-pin
connector on the SCA backplane.
The end of the cable has a molded conversion to 50 pins and terminator.
The cable might be 68 conductors to the terminator, but I don't know.
There is no reason it needs to be, and the wiring could be non-standard.
So crimping a 68-pin connector here might be risky, especially as a
replacement cable is $400.
I found this manual (page Figure 4-1, Page 4-2 or page 26 in the PDF)
shows the Sun solution, which is a 50 pin extension cable.
http://www.sun.com/products-n-soluti...06-4423-10.pdf
However, that is not cheap ($70, plus shipping) considering it is only 3
50-pin IDC connectors on a short length of 50-connector cable. I think
I'll make one of them myself. I can get the parts for about £5 (around
$7), so it is 10% of the price of buying one.
---
Dave K
http://www.southminster-branch-line.org.uk/
Please note my email address changes periodically to avoid spam.
It is always of the form: month-year@domain. Hitting reply will work
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