[G4] ATA buses, cables, and Cable Select - Q's and observations

[Aaron]

This is a slight update of something I wrote a week ago but didn't, apparently, post to the list. Since the listserver refuses to send me copies of my own posts to the list,I'm not absolutely sure. (;-<)

>From: Philip J Robar <pjrobar at areyoureallythatstupid.org>
>Subject: Re: [G4] Note on ATA buses in MDD Dual G4 and perhaps other Macs.
>Date: Sun, 13 Nov 2005 06:16:45 -0800

[SNIP]

>Keeping things simple. Cable select has nothing to do with which interface you're using. It has everything to do with having a cable select enabled cable (i.e. the correct wire is snipped at the correct location) and the drives jumpered to cable select.

I know that the manual for my G4 Dual says to use Cable Select AND to use the cables that came with the Mac to ensure that it will work. I also remember that the manual that came with my ATA card says NOT to use Cable Select.

I'm under the impression that the newer ATA cables will work with both Cable Select and Master/Slave bus controllers. Am I wrong about this?

I presently have two drives attached to the G4's built-in ATA-100 bus, with the drive at the end of the cable  jumpered for Master and the other jumpered for Slave. It seems to be working. The only problem I'd anticipate would be if the jumper settings were to contradict the positions on the cable. Any comments?

Another question about cables is, how does one tell if a cable can handle a particular ATA bus speed and will there be problems, other than slowness, if an inadequate cable is used to connect a fast device to a fast controller? Also, what is an 80-pin cable -- they look the same as other cables to me! -- and when is it necessary or beneficial to use one?

If there's a good document that answers some or all of these questions, I'd apppreciate a URL.

 - Aaron