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SCSI cable question regarding terminators

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jmille34

Programmer
Sep 14, 2005
224
US
This is all regarding internal scsi chains. Are there, or were there ever, scsi cables with 10 connectors on them, 8 for devices (1 being the card) and 2 for terminators? I know that many (if not most or all) cards have the capability to terminate the bus, either by jumper or bios or something. And many, if not most, internal devices can terminate as well. But I have some of these cables that came with terminators on them already at the end. I just want to know if you can have 8 devices PLUS 2 terminators, or if such a thing even exists.

The reason I ask is because I have a scsi drive that came with a low-end cable that only has 2 devices spots, one for the card, and one for the drive, and it has a terminator on each end, with the terminators on the very end and the device spots about one inch away. I want to know if full size cables would have 6 more spots in the middle or if the cable would only have 8 spots and require that the adapter and the last device both be capable of providing termination.

My question is more academic than practical, so if I'm looking at this the wrong way, please let me know.
 
Once upon a time, SCSI controllers did not terminate their end of the cable (any terminated cable is terminated at both ends, period), therefore cables had 2 terminators. Nearly all modern SCSI controllers terminate on-board, and many SCSI devices can as well. So you could see a valid SCSI cable with 0, 1, or 2 terminators on it.

Since a SCSI channel can run up to 16 devices (15 including the controller) you can find SCSI cables with up to 15 device connectors on them.

So, SCSI cables can come with 0, 1, or 2 terminators, and between 2 and 15 device connectors.
 
I would suspect that you would need to have a custom cable shop build you one with 8 plus dual terminators if you really needed one.
I haven't seen any cables with dual terminators, only singles. All the controllers I've seen have been either automatic termination or on board resistors. This covering 50 pin stuff for about 20 years.

Ed Fair
Give the wrong symptoms, get the wrong solutions.
 
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