Scan of Micro Peripherals Inc MPI 91/92 Product Manual Avail?

[Fred Cisin]

> On 10/5/18 4:21 PM, Chuck Guzis via cctalk wrote:
>> I seem to remember that there was a "combo" manual that covered the
>> 51/52, 91/82 and 101/102.   Also, there was a 52M, but I never
>> encountered it in the wild.

On Fri, 5 Oct 2018, Al Kossow via cctalk wrote:
> double sided 48tpi, with some micropolis-unique feature?

Interesting.

http://www.mfarris.com/floppy/mpi.html
shows 'M', 'S', and "M-S" suffixes.

In OTHER brands, the Tandon TM100-4M was much like the TM100-4, except 
with 100TPI, instead of 96TPI.  ("M for Micropolis compatible", and some 
of the TM100-4M drives did not have an 'M' on the nameplate!)

(For those not familiar, Micropolis made a 100 TPI drive, and a few 
companies made provision for that.)

But, what Micropolis features would be desirable in a 48TPI drive?
And what was the difference between a 92M, a 92S, a 92M-002, and a 102M-S

If it were "91"/"92"/"91M"/"92M", then that would seem comparable to the 
Tandon TM100-3/TM100-4/TM100-4M.

And what is the 101/102, if not 100tpi versions of the 91/92?

Course, thei all might be irrelevant if the differences were lead-screw 
(what my micropolis 48tpi had), V split band positioner, (like my MPI 
B51s, which were the only MPIs that I had)
OR difference in OTHER specs such as for faster drives?  (Lead screw tends 
to be slower than split-band)


Was there ever any brand of drive where the alignment of the second side 
head was a DIFFERENT offset than the USUAL offset from the position of the 
first side head?

Over the lifespan of 5.25" drives, there have been a few changes in some 
signals, such as READY, DiskChange, Density, etc.   Even to the point that 
Tandy used pin 32 for fourth drive select, and then the drive 
manufacturers used it for side select.