On 07/09/2017 11:16 AM, Paul Groves wrote:
On 09/07/17 17:23, Wols Lists wrote:
No that's not the question. A lot of SCSI devices come with built-in termination. Check the jumper documentation, and make sure all the internal terminators are disabled if you've got an external terminator.
If you have devices on all the blocks, there's nowhere to put a terminator which is why they do this, and which is why you should always have the terminator - or a terminating device - on the last block.
Cheers, Wol I can't see any mention in the manual of built in terminators. The jumper pins on all the drives are
Term Pwr Reserved SCSI_ID 4 SCSI_ID 3 SCSI_ID 2 SCSI_ID 1
I assume the Terminator power supplies the power to the terminator on the last block? This jumper is set to on on all the drives.
Only one drive needs to supply terminator power. It probably does not hurt to have more than one. If your drive doesn't have a jumper for termination resistors then it probably uses ACTUAL resistors. These look like this: http://images.slideplayer.com/25/7891558/slides/slide_24.jpg http://marina.mfarris.com/hard_drives/seagate/st3390n/3655n1.gif http://www.warp12racing.com/images/ataritt/ataritt18.jpg Use Scheme: http://www.craystone.com/dealer/page17.html The thing is, Paul that consumer gear almost always comes terminated because user buy exactly one unit, and can't get it to work if they forget the terminator. Commercial/Professional kit often comes un-terminated because the manufacturers know its going into enclosures which provide termination, and these resistors get thrown away in those cases. But dual use gear tends to come terminated as well. So look for them as physical resistor packs in a socket - not soldered, meant to be removable. The time honored tradition is to yank them from the drives that don't need them and tape them to the top of the drive where they remain till the day you throw it in the trash. -- After all is said and done, more is said than done. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org