PDP 11 floppy disk question. - test-drb@ccmp.vtda.org

28 Jun 2005

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Subject: Re: PDP 11 floppy disk question.
   From: Ethan Dicks <ethan.dicks at gmail.com>
   Date: Tue, 28 Jun 2005 17:00:20 -0500
     To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at
classiccmp.org>

On 6/28/05, Jim Beacon <jim at g1jbg.co.uk> wrote:
  A simple question, I hope!

 Can I use a normal 51/4" dsdd floppy drive with an RQDX3, in place of the
 twin drive RX50 unit? If so, do I need a special cable? 
The Teac FD55-GFR was commonly used on PCs and, when the jumpers are
strapped the way DEC did, _is_ an RX33.  There are some variations on
how some of the signals are presented (pins 2 and 34, IIRC) and how
motor start and select interact, so you _do_ have to check jumpers. 
Once you have a prepared FD55-GFR, it will go on the end of an RQDX3
just fine.  I know VMS has no problem with it, but I can't comment on
Unix or PDP-11 use.

If I had a pointer to the configuration, I'd post it, but I know such
things are hanging around on the 'net and in list-members directories.

-ethan 
The TEAC FD55GFR is the official RX33 (IE: dec bought and used the 
teac) and works fine with RQDX3 with the distribution pannel 
(ba23 or from BA123).  I have a vax and a 11/73 using that combo.

Allison