Path: utzoo!attcan!uunet!lll-winken!lll-lcc!mordor!joyce!ames!nrl-cmf!ukma!rutgers!iuvax!bkliewer
From: bkliewer@iuvax.cs.indiana.edu (Bradley Dyck Kliewer)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Hard drive / controller problems
Message-ID: <10657@iuvax.cs.indiana.edu>
Date: 15 Jul 88 04:56:18 GMT
References: <222@psuhcx.psu.edu> <16800327@clio> <230@psuhcx.psu.edu> <4452@sphinx.uchicago.edu>
Reply-To: bkliewer@iuvax.UUCP (Bradley Dyck Kliewer)
Organization: Indiana University CSCI, Bloomington
Lines: 31

>controller.  I was also using a cable with a twist between the 
>connection for drive c and d (or a and b, as the case probably was). 
>the controller could talk to one drive, or the other, but never both
>at once.  I called Everex (who, for some reason known only to them had
>marketed the WD-Seagate combination), and the (very clued-in) tech
>guy said, "well, you have both drives set to drive 2 don't you?"
>(silence on my end).  I finally said "Yea, sure I do, course I do, 
>waddya think, I'm a dummy, that's the ticket" and went and set both
>seagates to be drive 2 and the thing works great.  
>
>I have some idea how controllers work, and some idea how drives work, 
>but no idea why *that* worked.

Since there seems to be a lot of discussion on the topic of twisted 
wires on the controller cables, you might as well know what the twist
does -- it swaps the drive ID lines from between the two connectors.
This is done so that all drives are set to the same ID (who knows why,
I think it's pretty silly myself -- especially since they're all set
to 2).  So untwisted wires work the way any normal person would think,
drive 1 set to drive 1, drive 2 set to drive 2; but not twisted wires.

And, as has been mentioned, this is also done on some floppies.  Even
worse, I had to install a second drive on a Tandy 1000SX.  The edge 
connector on the card is upside-down from standard, and the cable is
extremely short.  So, I had to buy some ribbon cable and connectors,
make a longer cable, put in a few twists to invert the second connector,
and install the drive.  Isn't it wonderful how manufacturer's make little
changes here and there to prevent you from buying other vendor's parts :-)?

Bradley Dyck Kliewer                Hacking...
bkliewer@iuvax.cs.indiana.edu       It's not just an adventure
                                    It's my job!