On Thu, 25 Mar 1999, Fred Cisin (XenoSoft) wrote:
Does anyone
happen to have, in some vast catacombs of old manuals/docs,
the jumper info for a Panasonic JU-475-2GRJ 5 1/4" floppy drive? Or maybe
you can shed some light on what the following sections/jumpers might do?
. . .
I'm trying to get this drive working with my ATR8000 (recently resurrected
from the dead) and am not having much luck formatting disks with it. Any
help would be much appreciated.
The Panasonic (AKA Matsushita (AKA Shugart)) #475 is a "1.2M" drive.
The ATR8000 formats that I have seen were "720K" (in this case actualy
about 800K), also once known as "QUAD density", NOT "high density".
It'll
be a LOT easier if you can find a 5.25" 720K drive. In the case of the
Shugart/Matsushita/Panasonic, that would be the #465. (and #455 is the
360K model)
If you don't have a choice, then you will need to either jumper or modify
the drive for 300 RPM operation (default on 1.2M is 360RPM), and jumper
or modify the write current for low density operation (aka 360K mode),
while still permitting the 96TPI track density. Typically 1.2M drives
change the track density along with the recording density.
SOME revisions of the #475 could be set right, some required some
minor board modifications.
Thanks Fred, and Pete for the jumper info...
Yes, I've been informed that the maximum drive size on the ATR 8000 is
720K. The CP/M disks I have are for a 40-track, double-sided 5 1/4"
floppy drive. Unfortunately, my floppy drive supply is a bit low, and all
I have are a few Shugart DS/DD 360K drives and this Panasonic.
Thanks to the jumper info Pete sent along, I got the floppy configured OK
for 360K operation, and can format and read disks on it (although it is
the same as the two Shugart drives I had attached...). This drive *is* a
little different than Pete's; I have the holes/markings for some of the
jumpers he mentioned, but no posts, so I may be SOL on doing it the easy
way. And finding a 720K drive at auction for a couple of bucks is probably
the easiest way of all...
I've got a couple of 720K 3 1/2" drives on the way from Haggle, but I
really wanted to get a couple of 720K 5 1/4" floppies on there as well.
Question: Is one media supported more than the other when it comes to
reading/writing Atari format disks with a PC? I know that MyUtil does
something weird with the second side of a floppy (or is it on the Atari
side - something about it writing backwards?), but it'd sure make things
simpler if I could read/write at least 180K disks on the PC (without
using Prosystem)...