[Coco] Nitr0S-9 question

[Gene Heskett]

On Wednesday 15 August 2007, Bob Devries wrote:
>Gene,
>
>OS9Gen can't be hard coded for $1200 for the boot track, or else you
>couldn't write a boot file to a double-sided disk. OS9Gen must take into
>account whether the disk is double-sided or not, and at the very least,
>double the $1200 to still writte to track 34.
>
That $1200 is the size of the track Bob, not its location, so 90% of the next 
paragraph is based on the wrong assumptions.  I think.

>If OS9Gen will write to a hard disk (does it? In the assembler source file I
>have there's a compile-time switch to turn that on or off), then it still
>may get it wrong because the emulator disk image says that the disk format
>(DD.FMT) is $03, which according to my manual means Double-density, and
>Double-sided. This would mean that OS9Gen is likely to try to write the boot
>track starting at $2400. However, it may simply *not* write the boot track,
>if it decides that it isn't writing to a floppy drive, based on the value of
>IT.TYP.

Way back up the log, it was track 34, on side 0, regardless of the number of 
sides.  If it was a double sided disk, then the FAT bits were adjusted to 
cover the obviously higher sector locations on an LSN basis.  For a single 
sided disk, those allocations started at LSN 612(decimal) and went on to 630, 
18 sectors total.

If it is a double sided disk, then it would need to allocate sectors 1224 to 
1242 (if I haven't dropped the ball with kcalc here), and this is still well 
within the size of sectbuff as defined.

That said, it may be that Boisy and company have adjusted it in the most 
recent release.

[...]

-- 
Cheers, Gene
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