[Coco] Making my 80T 2S OS-9 Boot Disks boot able

[Robert Gault]

Stephen Fischer wrote:
> I just realized that the floppy controller in SHF15 was for the DISTO No-Halt and that may be why it
> may not boot.
>
> I keep thinking that the offset to the boot track is messed up by the conversion to a .dsk is the
> problem. That's why I asked the question for using DED. Double sided disk to single sided .dsk.
>
> So I must either find what I did for the original Jeff Vavasour's CoCo 3 emulator, Or try another
> disk. Someone wants to stay far far away from NitrOS-9 Level-I due to the decreased memory available.
>
> So it's OS-9 Level-I that needs to be booted in VCC, I just thought it was better to go with my last
> system which I want to get running anyway.
>
> Perhaps SHF13 OS-9 L-I V02.00.00 which may use SDISK.
>
><snip>

OK! Just looked at the .dsk image you posted and have made progress.
1) As is, the .dsk can't be read in either VCC nor MESS but can be read if mounted in Drivewire.
2) Seems the DD.FMT byte on LSN0 is not liked by current emulators.
3) I changed DD.FMT from $07 to $03 using my Basic COLORZAP program as DED would not access the disk.

Now I could read the SHF15.dsk image when mounted in VCC or MESS while running NitrOS-9. I could 
also BACKUP the disk under OS-9 to an 80 track double sided disk image via VCC or MESS.
So, what you need to do is:
1) Alter byte $10 on your SHF15.dsk image to $03 from $07 with a PC program if necessary.
2) Create and format (NitrOS-9) a new disk with cyl=50 sid=2.
3) Use a NitrOS-9 script for OS-9 Level 1 V2 to os9gen a standard bootable disk created in step 2.
4) Backup the SHF15.dsk to the new boot disk which should give you everything except T34 and OS9Boot 
on your SHF15.dsk.

With luck, the new disk should boot from VCC or MESS and work as desired. If not, you may need to 
separate all of the modules in the original OS9Boot file and replace CC3Disk with a standard one. 
Merge all the files back into a new OS9Boot file and copy that to the disk created in step 3) above. 
Alter LSN0 to point to the new OS9Boot, and do a Backup.

Confused! :) Well just send me private email and we can go over it step by step. Or I can just try 
to create a bootable copy myself and email it to you.

Robert