Transferring Files Between a PC and a Mac

Jan 27 17:02 UTC 1992

I have been contacted by the lady at the Ronald McDonald House to
do our first good deed (public service).  She asked me to do two 
things -- install Word 5.0 on her PC and somehow install a 3.5"
floppy into her AT.  Now, the first I can handle.  The second one
I may need some help with.

She wants to install the floppy so she can swap files with a Mac Classic
they also have in the office.  I'm thinking, however, that it might
be easier for them to connect the two computers with an RS232 cable,
and XMODEM the files between computers.  

So, does anyone have an opinion on this?  Can anyone give me a cable
diagram or pinouts for the Mac Classic?  Can anyone give me a copy of
a shareware terminal program for the Mac?

Thanks.

response 2 of 42:

Jan 27 22:10 UTC 1992

If she has two floppy drives in the machine now, and just wants to replace 
one, and the Mac will do IBM, it's a small matter physically. 3.5" drives
are better anyway, in my opinion. If it's an AT, it can probably even do
a 1.44 meg drive, no problem. 
Would the connection cost much to get going? I'd say do that if A: it's 
cheaper, and B: it's simple. Unless it's very very simple, I'd go with the 
drive.

response 4 of 42:

Jan 28 12:01 UTC 1992

The PC does not have a floppy drive, so one would need to be installed.
Do you know if that's all they need?  I mean does the PC need
some different cables or maybe even a different controller?

response 6 of 42:

Jan 28 12:45 UTC 1992

I can do the drive installation in to the PC too.  It should not
require a new card or cable if they want to add the 3.5" as a 
second drive or replace the second 5 1/4".  All floppy controllers
will handle at least 2 drives, though the cable may only have a 
connector for one drive.  I can also make up a new cable (or buy
one) if needed.  You may need to get hold of a 5 1/4 to 3.5" drive
adapter if the additional drive will go into a 5 1/4" bay.

Transfering files between the Mac and AT is no problem.  I do this
on a regular basis between my Plus and AT.  I made up a 6 conductor
cable between my Mac and AT and run Z-term on the Mac. and Telix on
the AT (Both shareware).  I set one up to receive files and the other
to send.  I like to use Z-modem because it'll do batch files and will
do auto-downloads as well as being fast.  No AppleTalk, etc. involved.
I don't have the cable pinouts at my finger tips, but can get them for
you if you decide to go this way.  My Plus does not have a SuperDrive
but the Clasic does.  It will read all pc disks with the Apple File
Exchange software that comes with all machines equiped with said drive.

response 8 of 42:

Jan 29 02:34 UTC 1992

I went and took a look at the machine today.  It's a true-blue IBM AT.
From the comments here, it sounds like they can simply buy a 3.5"
drive and stick it in.  They have a deal with MicroAge whereby they
can buy stuff at cost.  I'll call MicroAge and see what their price
is.

response 10 of 42:

Jan 29 08:07 UTC 1992

If the machine is a true blue IBM, the whole game has changed.
You will need a special controller with special drivers (read
expensive) from a third party source to get a 3.5" High or Low
density drive to work on an IBM AT. Thanks IBM.

response 12 of 42:

Jan 29 17:02 UTC 1992

That's what I thought I had heard somewhere before, but after some
of the responses here I was getting hopeful.  :(

Maybe it's time to retrench to the serial link idea.

response 14 of 42:

Jan 30 04:20 UTC 1992

We used to sell Procomm brand drives to people who needed this sort
of soloution, I think it ended up costing about $170.00. That's for
a controller (separate card from regular floppy controller), an external
drive, and the software to drive it. These things are a huge pain. The
City of Alma has spent at least $1000.00 in service time at $45.00/hr
having us "fix" their 3.5" drives after they screw it up somehow. I never
did figure out how they were doing this, but just reinstalling the 
software wasnt always the soloution. Their refusal to upgrade from 
IBM-DOS 4.0 to 4.1 may have been part of the problem.

response 16 of 42:

Jan 31 08:21 UTC 1992

If I remember right, hmm -- an IBM AT doesn't have an FDC in the
motherboard, -- that's on the floppy/hard disk controller.
Hardware-wise, though, it'll talk to the 720K 3.5" drives, at least,
without any trouble at all.  The only real problem is software -- the
IBM AT bios never heard of 720K 3.5" floppy drives.  You might be able
to get around that, though, by switching from the standard IBM bios to
one of the 3rd party ones, perhaps phoenix.  'Course, there may be
something I'm missing -- I can't claim to be real fond of the
monsters...

response 18 of 42:

Jan 31 12:12 UTC 1992

Will an IBM AT talk to a 720K 5 1/4 drive?

response 20 of 42:

Feb 1 10:07 UTC 1992

I know of no hardware reason why an AT couldn't talk to a 720K 5.25"
drive.  Software-wise, that's another problem.  It may take a bit
of work to brainwash the BIOS into pretending that, even though
it looks just like a 360K drive, it really has twice as many
tracks, and that to read 360K floppies, in fact, it needs to
double step.

The 1.2M 5.25" drive, incidently, is quite capable of reading & writing
720K floppies.  Dos isn't, but we all know Dos has problems.  On the
other hand, most versions of Unix for the PC know and understand 720K
quite well.  It's actually something of a standard -- the AT&T 3B2,
and Codata machines also understood the same format, and also,
with some minor effort, the Convergent Technologies miniframes, &etc.

response 22 of 42:

Feb 1 21:47 UTC 1992

  Yes, though an ST uses 3.5" disks:  even though it understands the
format you're going to have a heck of a time reading them...

response 24 of 42:

Feb 2 07:16 UTC 1992

Well, to be fair to IBM, the original IBM AT came out before the clone.
It's kind of hard to be better than the clone when you don't know
what the clone is going to be like.  Also, there weren't very many
3.5" drives out at that point -- it wasn't at all clear if the
3.5" drives or the 3.25" drives were going to win back then.