[Info-vax] Attaching an actual 3.5" floppy drive to SIMH-VAX RXV21 device?

[John E. Malmberg]

On 8/14/2012 6:55 AM, Bill Gunshannon wrote:
>
> Are you sure it was a VAXStation?  I can't imagine where he would
> have found room for an RX50 there and there is no way to hook up

The RX50 uses an RQDX2 or an RQDX3 controller.

There was a configuration that had an RX50 and a RD53 disk enclosed in a 
small pedestal.  I suspect that the controller was an RQDX2.

The RX33 became available shortly after and I seem to remember it 
required an RQDX3.

> external enclosured model on a VAXStation unless you had some wierd
> SCSI interface for the floppy.  They were common on early MicroVAX's
> though just like on the MicroPDP's.

The only early MicroVAX with a SCSI interface was the 
MicroVAX/Vaxstation 2000, and that was used only for the tape drive.

The earliest MicroVAX/VAXstation that would boot off of SCSI is a Q-BUS 
model 3500 (Later boot roms), which could boot off of the KZQSA option.

At one site, I found that the former system mangler had specified a 
number of MicroVAX IIs world boxes with RX23 drives.  He then had the 
users purchase RX50s to use to archive user data instead of using the 
standard off the shelf 1.2 M floppies.  They were very happy to switch 
to the higher density media and save space.  As they never saw the cost 
of the media directly, they never realized how much extra using RX50 
media had cost them.

As I understand it, the RX33 drives were a specific Teac drive with a 
special jumper configuration.  I to not think that you could just plug 
in any 1.2 M floppy drive and use it.

I have come into the possession of 2 RX50 drives and media that was 
allegedly written on by a VAX.  In testing them, I could not get either 
drive to read any of the media that I have tried.  I think I had the 
disks oriented correctly and the cables correct, but I was not totally 
sure about that.  Even it I had them working, I do not know what I would 
really do with them.

Regards,
-John
wb8tyw at qsl.network
Personal Opinion Only