[Coco] Hacking the SuperIDE

[Robert Gault]

Bill Pierce wrote:
>
> :-) Mr. Gault,
> Where do you think I got my info? The offsets used in HDBDOS/RGBDOS were genius. I was just experimenting a while back with the info from the white paper and created a system that manages 9x256 drives under HDBDOS. Each VHD is dedicated to something different, games, music, programming, utilities, ect. It uses a highly modified version of the "blue" startup program from RGBDOS. It's lists the drives and the "theme" for each drives and gives the option to select which drive you want. After selecting the drive, the menu reappears. Then you just exit to basic to be on that drive. Anytime you want to switch again, just run"autoexec:0" or reboot. To use this with RGBDOS and VCC the ROM would have to be modified to offset 000000 as it has to be able to read the drive0 to set up the system and no OS-9 drives are used. I wouldn't be much trouble to modify the program to read past an OS9 drive as well. It would just make the VHD even larger (372,096 already).
>
> Bill P
>

I haven't tested VCC but the technique works with MESS and should work with VCC. 
It is just a question of changing the data in ROM to indicate the start of a/the 
"Disk Basic" partition of the .vhd drive.
RGBDOS for MESS and VCC is the "parent" of HDBDOS so the same location is used 
for the 3-byte offset value.

It would be easy to use the default offset values to read in a menu program 
which alters the offset to any desired value. You don't need to actually change 
the ROM with Coco3 emulation as it runs in all RAM mode.