[Coco] Boot OS-9 from drive other than 0

[Robert Gault]

Bob Devries wrote:
> Could someone please tell me what modifications need to be made to allow 
> OS-9 to boot from a drive other than drive 0?
> 
> I'd like to boot from one of the virtual disks using the VCC Emulator 
> and its built-in RGB DOS. I'd like to be able to type: DRIVE 255: DOS 
> and have OS-9 start that way. At the moment it reverts back to dtrive 0 
> as soon as its read track 34 off the drive.
> 
> Ideally, I'd love to have a situation where it would boot directly from 
> the hard disk, with no (virtual) floppy disk at all. SIGH.
> 
> -- 
> Regards, Bob Devries, Dalby, Queensland, Australia

Make sure that the .vhd image has OS-9 installed on it. Then create a 
boot disk and install it on Drive255 as follows.

The boot module in the kernel must work with a .vhd image not a floppy. 
There must be a single sided .os9 image of 34 tracks copied to drive 255 
on the .vhd image. Drive 255 will then contain the kernel and the 
OS9Boot file which must contain hdrive and appropriate descriptors for 
the .vhd image. You must run LINK.BAS and indicate that the boot drive 
will be 255.

LINK will modify LSNO of the OS-9 portion of the .vhd image indicating 
that the boot file is on DRIVE255. In other words, an offset larger than 
the OS-9 .vhd image will be put DD.BT.

The RGB-DOS command for booting would just be DOS255. You don't need to 
use the DRIVE# command.

============
Given your description, I'd say you are using the standard floppy BOOT 
module rather than one for the hard drive.