[Coco] [COCO] Putting NitrOS-9 boot track in ROM

Gene Heskett gheskett at wdtv.com
Mon Feb 2 17:00:54 EST 2015


On Monday 02 February 2015 12:36:51 Allen Huffman did opine
And Gene did reply:
> > On Feb 2, 2015, at 11:02 AM, David Ladd <davidwladd at gmail.com> wrote:
> > 
> > I also tried os9gen with the -q=bootfile
> > Sadly nothing happened other than my device booted from old boot file
> > I also tried os9gen with the -q=bootfile /dd
> > Sadly this option left a temp file in the root of /dd and system no
> > longer booted.
> 
> DO NOT USE os9gen or cobbler on any hard drive with geometry that
> doesn’t look like a big floppy disk. It will not work, as best, or
> do bad things to your drive, at worst.
> 
> IF your hard drive is set up as 18 tracks per sector, single sided, it
> should work but you’d have a small hard drive.
> 
> If the drive is too large, it fails in other ways. It allocates memory
> for the size of the DAM. My DAM is $FFFF and it tires to allocate
> “$FFFF+256â€‌ which rolls over and only gives it 256 bytes and …
> bad things happen.
> 
> I gen mine manually for now until I write a tool that works like
> os9.exe.
> 
> I use a short B09 program to copy the boot sectors $264-$275 from one
> HD to the new one, then I use dEd to set bits in the DAM to mark those
> sectors used. Basically:
> 
> Offset $143 - $0F (00001111)
> Offset $144 - $FF (11111111)
> Offset $145 - $FC (11111100)
> 
> Then I copy OS9Boot over, and use dEd to mark where it starts and the
> size. I get the start and size from “dir -eâ€‌. But, where “dir’
> shows the file start is actually where the File ID sector is. If
> it’s a clean drive, OS9Boot is right after it. On mine, the dir said
> OS9Boot was at sector $88. If I open up dEd and jump to sector $88, I
> see the File ID for it, and in the segment list, the first segment
> used is $89. That’s the one I want.
> 
> Offset $15-$17 - 3 byte starting LSN (not what DIR reports, but what
> sector that File ID sector points to) Offset $18-$19 - 2 byte size of
> OS9Boot (from “dir -eâ€‌)
> 
> After that, just having sysgo, CMDS/shell, etc. is all it takes. I use
> dsave just like normal boot disks from there on out to copy over CMDS,
> SYS, DEFS, startup, SysGo, etc.
> 
> As soon as I get done with all my archiving, I’ll spin out a real
> quick assembly boot maker.
> 
> 		— A

HDBDOS and nitros9, combined, solve ALL those problems.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>
US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS


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