Need Jumpersettings for Panasonic/Matsushita Floppy Drive

[ba22...@hotmail.com]

Hello,
I need a manual/Datasheet for old Panasonic floppy disc drives model JU-256A216P or JU-257A726P.
The special on these drives is that the are used also in industrial machines (CNC, eroding machines). I know the function of the jumpers DS (Driveselect) RDY/DC and MO/MS. But what is the function from Jumper (SW5) labeld with PC/AT/P2/SE ? Particular I am interested in the setting SE, because this setting is used into the machines.

[Arno]

I have no idea about SE, but PCs read/write with 300kb/s, while ATs and
PS/2s read/write with 360kb/s (for DD disks).

Arno

--
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: ar...@wagner.name
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Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans

[do_not_...@my-deja.com]

Try sites that support the old Amiga computers because they had incompatibilities with certain floppy drives, and some of the Amiga sites documented floppies extensively and described modifications, one which involved interchanging pins 2 and 34. It may also help to search by the name Matsushita instead of Panasonic.

I vaguely remember SE standing for 'single ended,' but that makes no sense to me in terms of floppy drives, which use only single-ended signaling, not double-ended (differential) signaling. SE may refer to the use of termination resistors, which are normally left connected for all the 3.5" drives that are on the same cable, but with 5.25" and 8" drives only the last one on the cable had its terminators connected.

AT may refer to the IBM PC/AT standard, where the controller selected high or low density for the floppy drives set by leaving pin 2 high or by pulling it to ground, allowing 1.44M disks to be formatted to 720K (and vice-versa, but 720K disks used a thicker media that was not reliable at 1.44M). In contrast, IBM PC/2 floppy controllers didn't set the density but had that set by the drive type and an extra hole in a corner of the disk. I don't know what PC stands for, but it may mean the original IBM PC/XT standard, where the DC status from the floppy drive was ignored (allowed to stay high).

Panasonic made some unusual 3.5" floppy drives that supported 360 RPM and a 1.2M format identical in sectors/track to the 1.2M format used by high density 5.25" disks, some which could spin at either 300 RPM for low density or 360 RPM for high density. Grounding pin 2, the high/low density signal, may cause the RPM to change, and you should hear a slight knock if it does. RPM can also be read by painting 20 marks evenly around the circumference of the spindle motor and using an old-style fluorescent lamp with 60 Hz AC ballast and audible hum. Compact fluorescents won't work since they use a much higher frequency, as do some ballasts. If the drive spins at 300 RPM, those marks will appear still, but at other speeds they'll just look like a blur. For 360 RPM use 24 evenly spaced marks.