PDP 11 floppy disk question.

[Doc Shipley]

Ethan Dicks wrote:

> 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.

   Using a TEAC FD55GFR-149-U7 with my 11/53, and it's good with RSX11M+ 
and RT-11.

   I have a couple of FD55GFR-7xxx drives, and I haven't found a jumper 
setting that works for them.  I think bridging a couple of solder pads 
would get them there, but I haven't needed an RX33 that badly yet.


	Doc
> 
> 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
>