Mike McCarty: >> If you use M/S jumpering on the drives, then in theory it doesn't matter >> where you connect them. bobgoodwin: > Except it appears to me that it matters as far as terminating the line > properly is concerned. Ideally it would seem the termination should be > at the far end where the master is connected to avoid the possibility of > a mismatch at the end of the stub that would result if the slave is at > the far end. Theoretically, you should terminate the cable at both ends with something. I would expect to see problems with a cable flapping about. I've seem old IDE systems wired up in all sorts of ways without problems. I've seen systems come in with problems, but you're never quite sure if just fiddling with the cable fixed things, rather than changing the position, unless you prove the cable is intermittent by repeatedly poking it about. If it seems slightly dodgy I'll replace it, they're so cheap and it's not worth the headaches. Most cables aren't meant for repeated plugging and unplugging anyway, so if you've got a fiddler's broken box on your hands, there's a very good chance that they've worn out the contacts, or wrenched the ribbon out of the IDC connector teeth. > How much ringing might occur and the severity of it's effect is an > unknown? It would be interesting if I could get into the circuit and > poke around with a scope probe ... You'd have to be careful that the measurement, itself, doesn't affect the readings; which is quite likely with such high speed data. You'd also need to know how much ringing was tolerable by the specs, anyway. > If the h/d manufacturer provided this explanation this thread would > never have started. I would have never asked any questions. It appears > that I probably have cable select which I will try here in a little > while. The drives can be jumpered for CS and I have 80 wire ribbon > cables so it appears that should work if I understand everything I've > read here? It would be helpful if the user knew that he was dealing > with a c/s cable, there is no mark apparently other than the fact that > there are more wires than connector pins to tie them to? Yes, it doesn't help when you get unlabelled jumpers on drives, new drives in a bag with no instructions, and manufacturers with useless websites. I have yet to find a system that won't work with manual jumpering, and it's what I always use. If it works, there's no point in caring if the cable is cable-select. If it doesn't work, you've only got a few variations that you need to try. But I'd be most suspicious of: (a) crap cabling which ought to be replaced, and (b) a broken drive which is likely to cause you other grief, too. Probably the worst aspect to jumpering drives is finding out that you need two jumpers in the block, for your situation, but the damn manufacturer only supplied one! -- Don't send private replies to my address, the mailbox is ignored. I read messages from the public lists.
