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

[Bill Gunshannon]

In article <MsGdnc67Hcro3rfNnZ2dnUVZ_gKdnZ2d at mchsi.com>,
	"John E. Malmberg" <wb8tyw at qsl.network> writes:
> 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.

I know all this.  As a matter of fact, I have quite a few of them here.
But......   We are talking VAXStation here.  That's a desktop pizza box.
Not a QBUS system.  No where to put an RQDX-anything and no room for a
drive the size of the RX50.

> 
>> 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.

Sorry, I didn't mean SCSI I meant external enclosure.  Connected to
the RQDXE.  But some quick research shows that was hard disk only so
it looks like there was never a system that allowed an external RX-50.

> 
> 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.

I think you meant RX-33.  That was the 1.2M 5.25" drive.  

> 
> 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.

Don't know what DEC actually used but today you want TEAC FD55-GFR's
which work quite well with DEC Controllers and using DEC formats.

> 
> 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.
> 

I have a number of RX-50 drives.  I almost never use them as they were
unreliable and can easily be replaced by the TEAC.

bill

-- 
Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three wolves
billg999 at cs.scranton.edu |  and a sheep voting on what's for dinner.
University of Scranton   |
Scranton, Pennsylvania   |         #include <std.disclaimer.h>