[Coco] No Nitr(OS-9) in this coco

Mike Pepe lamune at doki-doki.net
Fri Aug 4 22:39:41 EDT 2006



Diego Barizo wrote:
> For about a month or so, I didn't use any OS-9 disk, but when earlier 
> this week I went to try a few games, I found that most disks will fail 
> in the boot process, including my custom Nitros-9 disks . This fail 
> after the usual i2xo and then repeats KREL until the screen is filled.
> But when I tried that same disk in a PC running DK's emu, reading the 
> real disk from a 1.2 MB drive, all worked out perfect.
> BASIC disks work also 100% OK on the real coco that refuses to load OS-9.
> In conclusion... the disk is OK because it works with the PC emulator.
> And the drive/controller is OK because it works with any non-OS-9 disk 
> (including games like Ghana Bwana that don't use the standard BASIC format)
> 
> Any clues?
> 
> Diego
> 
> 

Yes,

Assuming you're writing the disk on a 1.2M drive and trying to read it 
on a low density CoCo drive, you may be running into head width issues.

In a nutshell, the 1.2M drive writes tracks that are half the width of 
the 40 track ones. Your 40 track drive might not be able to read it 
properly.

If that's the situation, the best thing to do would be to bulk erase the 
disk and try again.

If you move over to 3.5" disks, that problem will go away.

-Mike



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