From owner-freebsd-questions Fri Sep 12 17:41:47 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id RAA21645 for questions-outgoing; Fri, 12 Sep 1997 17:41:47 -0700 (PDT) Received: from freebie.lemis.com (gregl1.lnk.telstra.net [139.130.136.133]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id RAA21640 for ; Fri, 12 Sep 1997 17:41:43 -0700 (PDT) Received: (from grog@localhost) by freebie.lemis.com (8.8.7/8.8.5) id KAA23150; Sat, 13 Sep 1997 10:11:33 +0930 (CST) Message-ID: <19970913101132.23596@lemis.com> Date: Sat, 13 Sep 1997 10:11:32 +0930 From: Greg Lehey To: Robert Clark Cc: questions@FreeBSD.ORG Subject: Re: Floppy Trouble / Cable Select. References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.81e In-Reply-To: ; from Robert Clark on Fri, Sep 12, 1997 at 09:05:16AM -0700 Organisation: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8250 Fax: +61-8-8388-8250 Mobile: +61-41-739-7062 WWW-Home-Page: http://www.lemis.com/~grog Fight-Spam-Now: http://www.cauce.org Sender: owner-freebsd-questions@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk On Fri, Sep 12, 1997 at 09:05:16AM -0700, Robert Clark wrote: > Scenario: > > You have two floppy drives in your PC. For some reason, you would like > to swap A: & B:. Your BIOS won't do it. > > You reach into the case, and move both drive select jumpers from 0 to 1. > (Or is it the opposite?) No. From 1 to 2. > Now drives A: & B: are swapped. The controller can address four units, 0 to 3. It outputs the drive number in binary on two drive select lines. You all know what a floppy cable looks like: it's a kludge, they've torn the flat cable apart and swapped the drive select lines. This means that you don't need to set the jumpers on the floppy itself. They're both set to 1. The system addresses /dev/fd1 as unit 1 and /dev/fd0 as unit 2. The swap in the cable swaps the two address lines, so the second floppy responds to address line 1 (the '2' bit) instead of address line 0 (the '1') bit. > Problem: Things get weird. Some systems don't like this arrangement. They can't tell. It's the same as swapping the cables. Of course, it's important to change both drives. > Would this affect FreeBSD? No. But why would you want to use floppies with FreeBSD? Greg