On Wed, 2005-04-13 at 11:53 +0900, Joel wrote: > Okay, I spent a little more time at the place that explained UDMA > (pcguide.com) and I answered my own questions: > > > [...] > > > Cable select is exactly what it says, and is VERY reliable in my > > > experience. > > > > I used to repair computers with 5 1/4" floppy drives, and in those days, > > CS was an epithet. Been a while since I've messed with mainstream > > hardware. I'm going to have a lot of bias to get over if CS really is > > reliable these days. > > > > > -Use a cable select cable > > > -plug the drive to be used as master to the connection designated as > > > master. > > > -plug the drive to be used as slave to the connection designated as > > > slave. > > > > So, if it's a CS cable, it should say on the connectors something like > > "motherboard", "master", and "slave"? If it doesn't say, I can assume > > the guy at Pasokon Koubou knew I didn't want a CS cable? Or maybe this > > whole business is why he didn't want to recommend using the slave > > channel in a multi-drive, multi-boot setup? > > Blue is motherboard. > Gray is slave. > Black is master. > If you put a hard disk and a CDROM on the same cable, the cdrom should be the slave. At one point the CDROM could not act as master for a hard disk. I understand some of the newer ones can do so now though I have never tried it. > > I guess I'd better take a look when I get home tonight. I don't want the > > drives fighting with the cables on my new cheap Linux/BSD sixOS > > multi-booting toybox. > > Pin 28 is grounded for master, floats for slave. If CS is selected on > both drives, the controller checks pin 28, but if one drive is selected > as master and the other as slave, the controller ignores pin 28. > > So, other than you want to put the master at the end anyway (to avoid > data reflection on a non-terminated cable if you happen to remove the > slave), as long as you make sure that one is selected master and the > other slave, you're okay. > Generally, in my experience, intermittent errors can sometimes occur on a CS cable with the drives jumpered as master/slave. I have never had a problem with the drives set to CS though. > Or you can let the cable select them. > I _always_ let the cable select them. > That's good to know. > > Thanks, guys, I guess I needed a reason to look that up. Glad to help.
