Re: How many 5.25 inch floppies with the IIc support

[Mike <mike@bogus.address.net>]

David Betz wrote:

> Can I connect more than one external 5.25 inch floppy to a IIc? Can the
> IIc support external 3.5 inch floppies? If so, how many?

For the 5.25, just one external drive.

Now, for the 3.5, that's a different story.  If you look on the bottom and 
your IIc says "Model A2S4100" you are in luck, and your IIc supports a 
UniDisk 3.5, for sure (among other things).  If it's A2S4000, maybe it does:

Turn on the IIc and hit control-reset after "Check Disk Drive" appears.  
Type the following

] CALL -151<enter>
* FBBF<enter>
FBBF- ??
*

Now, the ?? is key, here.  If it says anything but FF, you are in luck, and 
your IIc supports a UniDisk 3.5.

If it says FF, you are pretty much screwed unless you like soldering on the 
inside of your IIc, and have a way of burning a new ROM chip.

Some tech notes on the IIc ROM versions are here:  
http://web.pdx.edu/~heiss/technotes/aiic/tn.aiic.7.html

Now, the ONLY 3.5 drive you can connect to the IIc is the "UniDisk 3.5", 
not the "Apple 3.5 drive" or "Apple SuperDrive."  The UniDisk 3.5 has it's 
own processor on-board because the IIc is not fast enough to control the 
mechanism like it does the 5.25 drives.

If you plug in any other drive besides the UniDisk 3.5 or Disk IIc, it will 
void the warranty on your IIc. :)

I've heard of damage possibly being done to the IIc by plugging in a 
non-UniDisk 3.5, but no confirmations.

Oh, and if you have an A2S4100 Apple IIc that says $FBBF = $04, I might 
want to talk to you about getting a copy of the ROM chip., since mine is a 
$03, and I want the terminal mode in the serial port to work.

Mike