non-DEC-compat HW to read RX02's? - test-drb@ccmp.vtda.org

9 May 2009

...

Subject: non-DEC-compat HW to read RX02's?
   From: shoppa at trailing-edge.com (Tim Shoppa)
   Date: Sat, 09 May 2009 08:32:25 -0400
     To: cctalk at classiccmp.org

What non-DEC-compatible stuff out there can read RX02's? 
DSD880 and a few of the floppy contoller replacement boards.

...
 Obviously the original RX02 drive can read
RX02's... as can all the
DSD, Sigma, etc. Q-bus, Unibus, Omnibus compatible controllers.

But what can read RX02's using a generic SA801-type drive and a PC-clone? 
Sigma, and DSD.  Those used generic drives.  The problem is not using 
a generic drive its the encoding by the controller the drive connects
to and generic PC controller (ala 765) is MFM and the DD mode of 
RX02 is M2FM a different thing.  Add to that the RX02 uses mixed
SD and DD on the same track means none of the available (then or now)
integrated FDCs can produce or read that format.

...
 Several years back I built a doohickey that plugged
into a PC's
parallel port and allowed me to step floppy drives and read
bit-timing-information, a track at a time, into a RAM buffer, which
I then dumped into the parallel port and wrote some software
to analyze arbitrary disk formats. I wired the index/sector hole
detector to the MSB RAM line and used it with great success to
analyze and read several 8" and 5.25" hard-sector
floppy formats and eventually pumped a few thousand disks through
the scheme. Not bad for something thrown together on a solderless
breadboard using random TTL chips I had lying around the basement :-). 
That is what you would need.

...
 Obviously similar devices have been discussed here in
the past
decade or two. Is there anything available off the shelf that
can plug into a USB port and let me do similar? Right now the
thought of traveling with a 8" HH floppy drive and a laptop
has a certain appeal as opposed to hauling around a BA23 and
a DSD440 :-). 
No, not without custom programming.

Allison