[Coco] VHD 256 or 255 disks

[Robert Gault]

Luis Fernández wrote:
> For more clarity is empty 255 disk for RSDOS
>
> and this format OS9 or Nitros9
> Partition used to boot the VHD Nitros 		 	   		
>
> --

Luis,

I don't understand the above. I have changed the info on the number of Disk 
Basic drives.

In any case, there is more information in the zip file with instructions for 
installing this Disk Basic. How RGBDOS and now HDBDOS works will become apparent 
with use.

The biggest problem with describing both RGBDOS and HDBDOS is that a hard drive 
can be almost any format, at the wishes of the user. All that needs to be done 
is to change the Disk Basic offset value in the ROM.
You can have a .vhd drive without an OS-9 partition. You can not bother to 
format any of the Disk Basic section and just use OS-9. There are other 
modifications that can be done including having multiple blocks of 256 Disk 
Basic drives.
Further complications are that of course any of the 256 Disk Basic drives can be 
formatted for OS-9 and work just fine that way.

Drivewire and HDBDOS for Drivewire has confused the issue further as that HDBDOS 
has an offset value of $000000. So if you mount a .vhd image in Drivewire, you 
will not automatically be able to read the Disk Basic section with a .vhd that 
is split between OS-9 and Disk Basic.

Robert