Apple Disk Transfer
Apple Disk Transfer
I'm very interested in the topic of imaging floppies right now. I'm try to get the 500 or so floppies of mine on optical disk to preserve them before they all suffer from bit rot.
I recently started this effort. 300 of the 500 disks are PC disks, so I thought that would be a good, easy way to start. I was quite shocked to find out that about a third of the diskettes have had read errors! So now is the time to be archiving those disks!
I did some research what appears to be the best image format for a number of the old formats.
For the Apple 2, non-copy protected diskettes, I think the best approach is to use a program called Apple Disk Transfer. It's described here:
http://home.swbell.net/rubywand/Csa2FLUTILS.html#006
The issue with A2 disks, of course, is that it uses a different method of encoding the data stream and clock pulses into the signal that's written to the floppy. It's referred to as group code recording (GCR), which can't be read by standard PC floppy disk controllers (they use MFM controllers).
So the basic idea with ADT is that you're running a program that reads the floppy, transfers it over the serial port to a PC, and another program writes the image to a disk file. So it's the Apple that does the reading.
I haven't tried it yet.
One consideration is that I've run across imaging approaches that are designed to read a floppy and create a disk image for use in a PC-based emulator. While this is fine, I also would like to be able to write back a floppy because I have the old hardware!
Finally, the other possiblility is the Catweasel Mk 4 card. It's a universal floppy controller that can plug into a PCI slot.
I did happen to buy one, but I haven't had a chance to try it out yet. I'm still having fun with all of those PC floppies!
I will say that the Catweasel software is a little basic. I need to play with it more to gain a better understanding of what it's doing. However, given that this is a rare peripheral to have, I'd like to exhaust more generic disk imaging methods first before resorting to it.