[Coco] Connect CoCo Floppy drive to Windows PC

[Robert Gault]

Fedor Steeman wrote:
> Thanks, Robert. That sounds like some interesting and important information
> for my little endeavour.
> 
> Right now I stand with a huge library of hundreds of diskettes that I would
> like to store on my hard disk as virtual floppies and then make available
> through the internet. Until now I would backup these (5.25" floppies) to
> 3.25" floppies using the CoCo and then would read them in on the PC. Of
> course, that is a bit tedious for so many disks. So it seemed to me I would
> save a lot of time if I could leave out the CoCo out of the equation and
> read the floppies in directly on my PC instead. The drive I wanted to use to
> this end was previously used to read and write these same disks.
> 
> Are you saying that I can save the trouble and keep on doing the backing up
> on the CoCo, because success is far from guaranteed with doing it directly
> on the PC?
> 
> Cheers,
> Fedor
> 

If you are lucky, you can hook the 5.25" drive to the PC and read the 
disks directly. That will require your PC can work with your 5.25" drive 
and, as others have explained better, the disks were formatted such that 
the PC can read them. See Bill Barnes message replying to Torsten's 
replying to mine.

Let's say you are lucky. Then the best bet for a neat storage of your 
disks is to use the VCC emulator, which can read real floppies, attached 
to a .vhd hard drive image holding as many multiples of 256 Basic disks 
as you desire. You can just BACKUP the real floppy to an RGBDOS .vhd 
drive #.
If you are not lucky, you will need to use an intermediate transfer from 
the Coco to the PC. It could be a 3.5" disk (formatted on the PC as a 
Coco disk) to transfer data or a null modem connection using Ultimaterm 
and a PC terminal program.
If you are not lucky it will be a lot of work to transfer the files, 
unless you can make use of Roger's future CocoNet or perhaps DriveWire 
from Cloud-9.

As regards the .vhd hard disk image, RGBDOS permits changing the Disk 
Basic offset values stored in the "ROM" on the fly. That means you can 
easily access Mx256 drive #s where M depends on how large you make the 
.vhd image. Of course you can just have more than one .vhd image. The 
only restriction is the offset value must fit in three bytes. The 
largest offset is thus $FFFFFF bytes.
This technique is also useful with a real Coco3 hard drive system from 
Cloud-9. Use a large IDE drive and you can do the same thing with HDBDOS 
  just by POKEing new offset values into the correct DOS locations.