[Coco] Floppies to PC or other OSs

[Phill Harvey-Smith]

On 13/02/2013 14:42, John E. Malmberg wrote:
> On 2/12/2013 9:26 AM, Daniel Campos wrote:
> If you have Windows 98 or earlier, it is easy to implement a DISK
> utility to read/write coco disks with 256 byte sectors.  Several exist.
>
> They also appear to exist for Linux.

setfdprm and dd work fine for transfering CoCo images to disks and disks 
to images.

> With Windows/XP and later, Microsoft removed the API for setting the
> floppy sector size.

While this is true there are replacement floppy drivers that will allow 
you to access disks with 256 byte sectors, if you are prepared to do a 
little coding on the PC end.

this can be found here : http://simonowen.com/fdrawcmd/

I've used this in the past for reading BBC micro disks that are single 
density 256 byte sectors.

> However, any unmodified COCO disk controller with any DISK basic ROM is
> quite happy to read and write 512 byte sector disks, as long as you have
> READ and WRITE verification off.
>
> The BASIC routines can only access the first 256 bytes of the sectors to
> read and write, but you can access the rest with PEEK() AND POKE().

I even managed to get a DragonDos controller to read a High denisty disk 
by clocking it at 2MHz (instead of 1MHz), and configuring it as if it 
where connected to an 8" disk which uses the same data rate as a 1.44MB 
HD disk. I did have to use the high speed poke and have the code in ROM, 
for the 6809 to keep up with the data rate.

Cheers.

Phill.