[coco] For Boisy or Mark ref Super Driver

[Boisy G. Pitre]

--
Boisy G. Pitre
E-Mail: boisy at boisypitre.com
Mobile: (337) 739-7584
Web: www.boisypitre.com

On Sep 17, 2004, at 4:20 PM, <alsplace at pobox.com> wrote:

> Boisy,
>
> I haven't dug into the docs yet (I assume this is covered there), but 
> care to talk a bit about accessing HDB-DOS partitions via 
> SuperDrivers?  I assume you can make a descriptor that knows how to 
> seek out to where those sectors are stored, and somehow understands to 
> only look at the 256-bytes at the start of each sector?  (So I could, 
> by theory, use the "rsdos" command to put/get things from an HDB-DOS 
> drive?)

It is in the documentation, and in fact there is a device descriptor on 
the disk that is already set up for HDB-DOS access.  It goes something 
like this though:

There is a bit that must be set in one of the descriptor fields (don't 
remember which bit or which field) that tells rbsuper to only look at 
the first 256 bytes of a sector.  Of course, this is how HDB-DOS works 
-- it ignores anything past the first 256 bytes of a sector.  Once that 
bit is set, you need to plug in your "OS-9 OFFSET" that HDB-DOS has 
(the 3 byte value at $D938-$D93A).  You can use dmode to do this, say, 
if your offset was $017800:

	dmode /sh wpc=1 ofs=7800

That tells rbsuper to add $017800 to any LSN it receives, and of 
course, it passes the new LSN down to the low level driver.  Remember, 
the low level driver has no idea what an HDB-DOS partition is, or any 
partition for that matter.

Finally, you set the actual HDB-DOS "drive" to access through the 
IT.STP field of the descriptor.  This field is not used by rbsuper, and 
so, if you wanted to access the vitual disk 255 you would type:

	dmode /sh stp=ff

And there you go.  Doing dir /sh would yield the directory of the 255th 
drive on the HDB-DOS partition (presuming there's a valid OS-9 disk 
there.)  You can use os9gen to create a boot disk on that drive, etc.  
All works normal.

> I am also needing to brush up on getting a boot image onto HDB-DOS.  
> If I recall, with the old Kenton stuff, I would make a boot floppy 
> that included the Kenton "boot" module, then simply back that up to an 
> RGB-DOS drive and run a link utility on it, allowing "DOS #" to boot.  
> Has any of that changed?

No, all the same, except the boot module may have been updated.  I can 
send you that too for testing.

> I plan to make Sub-Etha's MultiBoot available, which allows up to 16 
> os9boot files to be put on one disk (though this may or may not have 
> assumed 40 track double sided; I forget -- regardless, it's limited by 
> disk space either way).  Then, I'd like to create an easy way to 
> manipulate all of that from the OS-9 side so no trips to RS-DOS were 
> needed.  Hmmm.  Might already be done???
>
> It will be awhile (possibly mid-late October) before I can really 
> start looking into this.
>
>     -- Allen
>
Don't loose the fire before then!

Boisy