MITS had custom drives that were larder (more bits) in the same format.

That might be what you are fighting. It was designed for IBM and likely
used in other divisions and other MITS companies. Yes not all MITS are MITS.
Color of the diamonds is a key. Red and Yellow... I had friends on both sides.

Martin [ former MITS DRAM ENG MANAGER N.A.]

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 6/6/2010 9:08 PM, David R.Birch wrote:
Michael A. Terrell wrote:
"David R.Birch" wrote:
Right now we'd be happy if we could load files from anything other
than the failing floppy drive. The control has a db25 serial port, but
for some reason, Mitsubishi decided that just being able to transfer
files with a COM program shouldn't work.


There are solid state replacements for 3.5" floppy drives, but they
aren't cheap. They allow you to use a USB memory stick to load programs
or data in CNC machines and other, old computers & computer based
systems.

http://hxc2001.free.fr/floppy_drive_emulator/index.html is one type.

This is a possibility, we're already using flash drives to load programs
to our newer Mazak, but I'd rather get everything networked.

What type, brand & model floppy drive are you using? There may be a
replacement, or if it is an older, full height 3.5" a good clean & lube
of the bearings in the disk elevator may fix your problems. I used to
repair 3.5" floppy drives when they cost $75. Dry bearings and missing
springs were common. Drives with bad heads gave me a good supply of
donor parts.

If it is an oddball drive, photos would help. I currently have a
couple hundred used floppy drives on hand. They are leftovers from a
closed computer business, and others were removed from scrapped computer
systems.

It looks like a standard half height 3.5" floppy drive, but it isn't.
I've tried substituting new drives, but the control doesn't read them,
so Mitsubishi seems to have monkeyed with them so they can charge $700+
for them.

David