On Thu, 2006-02-23 at 17:41 -0500, bobgoodwin wrote: > Mike McCarty wrote: > > > bobgoodwin wrote: > > > >> Mike McCarty wrote: > >> > >>> bobgoodwin wrote: > >>> > > > > [snip] > > > >>> If you use M/S jumpering on the drives, then in theory it doesn't > >>> matter > >>> where you connect them. > >> > >> > >> > >> 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. 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 ... > > > > > > Agreed. > > > > [snip] > > > > > >>>> I thought "cable select" cables had wires obviously crossed in the > >>>> ribbon cable but that may not be true with this 80 wire ribbon? > >>> > >>> > >>> Not crossed. For CS, the drives have resistive pull-ups on them. The MB > >>> pulls down one line. The wire to this line is *severed* as the slave > >>> connector, so the "master" sees a high, while the "slave" sees > >>> a low on this pin. (The MB may have a pull-up and the drives > >>> a pull-down, I forget the polarity.) > >>> > >> If the h/d manufacturer provided this explanation this thread would > >> never have started. I would have never asked any questions. It appears > > > > > > Well, just how much of the interface should they document? Each pin? > > Just the Cable Select pin? > > > >> 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? > > > > > > Color of the connectors. Usually non-CS cables use just one color > > of connector, presumably because they can get better volume > > prices that way. CS cables are supposed to use blue for the MB > > connector, black for "master" and grey for "slave", IIRC. > > > > Mike > > Ok, I jumpered the drives c/s and the computer can deal with that. As > long as the one set up for FC4 is on the master connector it boots and I > can see the second drive. > > The problem arose from the fact that I suspected an intermittent drive > problem. Apparently the failure was on the Windows drive while I was > only using FC4 and MySql! I ran smartctl and it indicated that both > drives had a lot of use on them. One looked like more than four years > power on time! I assumed it was the bad drive and rep[laced it with > another low time drive I had and then I began to have trouble. The > computer would not boot no matter what I tried. > > Now I pulled the one I thought to be usable [but is bad, I just tried it > again] and replaced it with the "bad" drive I had set aside and the > computer will boot FC4 with that drive plugged into the c/s master > connector. Hwbrowser and fdisk show both drives. So next to start over > and install W2k on the other drive, I guess Windows will want to be the > master and I will most likely wind up reinstalling FC4 with grub in the > MBR on the Windows drive. > Windows *prefers* to be the master. It should be the only drive in place when you do the install. Grub has options that allow the use of a windows drive as the slave with your fedora drive as the master. (see the map and chainloader commands). > If nothing else I have learned something about configuring hd and their > jumpers ... > > The information has been helpful and appreciated. > > BobG > >
