5-1/4' drive on modern PC

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Fri Dec 10 18:17:50 2004

> There was an attempt to "simplify" connection of multiple floppy drives
> (meaning TWO) at one time by adding a "twist" to the cable-- some
> conductors in the ribbon are cut out and reversed, which is a sort of
> "cable select" for floppy drives.
> I seem to recall in this case that one would jumper both drives as drive A
> in such a case, or as DS0.

I tought it was actually DS1.

> Stupid idea. Use a straight thru floppy cable and jumper one for DS0 and
> one for DS1. We get it.

The 'IBM twist' also gave you sparate motor-on lines for the 2 drives,
and the original controllers (XT and AT) certainly controlled them
separately. You can't normally get away with an untwisted cable, no
matter how you jumper the drives.

Received on Fri Dec 10 2004 - 18:17:50 GMT

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