Long Live the Quad was Re: NO QUAD (Was: 3B2 floppies

14 Feb 2013

...
   There are
high-density 5.25" drives made by Matsushita and a few others
 that do not offer a low-density (250K) mode for use on the PC98 platform. 
 The first "1.2M" drive that I got was Mitsubishi, and had a 50 pin
 connector!  I suspected that it was targeted at 8" 

My first CP/M system was a Pulsar Little Big Board machine that I built
with dual Mitsubishi M4854 drives - For quite awhile, I was the only person
on my block (and probably in my suburb) with 2.4Mb of storage online.    It
took quite a while to get media that worked ok...  They had 34 pin
interfaces, but worked great as 8" drive replacements with an adapter
board.

So Much Storage!!!   So few copies of Mbasic!

...
   Some PC98
drive interfaces require "disk-changed", "ready", and
"in-use"
 signals as well as drive select 0-3.  It makes sense--the "in use"
 allows software to determine if a drive is present, regardless of
 whether or not it has a diskette inserted.  "Ready"  likewise makes
 sense.  It can be challenging finding replacement drives. 
 Surely we don't really need 17 grounds, . . .

I thought that the interleaved grounds were used to reduce crosstalk.  In
that case, we needed them :-)

...
  --
 Doug Jackson
VK1ZDJ
http://www.dougswordclock.com/  -< My clocks
http://www.vk1zdj.net -< My Amature Radio Activities

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Long Live the Quad was Re: NO QUAD (Was: 3B2 floppies