Date   : Thu, 07 Mar 1996 11:59:37 +0000 (GMT)
From   : sf4000@... (Steven Flintham)
Subject: Connecting three disc drives

I have (or will have, when I get a cable made up :-) both a twin 5.25
inch drive and a single 3.5 inch drive. What I want to do is connect
both to my BBC at the same time with a switch so that drive 1 can be
either the second 5.25 inch drive or the 3.5 inch drive. There are two
(related) problems:

1. Will it suffice to put a switch in the drive select 1 line so that
the signal only ever reaches either the 3.5 inch or 5.25 inch unit,
with all the other signals going to both drives at all times? I assume
terminating resistors won't be a problem as both the second 5.25 inch
drive and the 3.5 inch drive should have one, but this is just
guesswork. If this won't work, how can I do it?

2. How can I wire whatever is necessary up as simply as possible? I
can't think of any 'nice' way of setting up the cables which isn't
going to be a real bodge and probably stop working every five seconds.

Any advice would be much appreciated.

Steven