[Coco] Playing around with SuperIDE CF

John W. Linville linville at tuxdriver.com
Mon Apr 30 13:13:25 EDT 2012


On Sat, Apr 28, 2012 at 09:18:14PM -0400, gene heskett wrote:
> On Saturday, April 28, 2012 09:16:11 PM Mark McDougall did opine:
> 
> > On 29/04/2012 1:27 AM, Paulo Lindoso wrote:
> > > dd if=cf-dump.dsk of=os9disk1.dsk count=315 (315 512-byte block will
> > > yield a 160K disk)
> > 
> > It's too early in the morning and I'm half asleep atm but 315 doesn't
> > look right for a sector count for any disk to me...
> > 
> > Regards,
> 
> That is in the usual 512 byte sectors dd uses by default. dd can, and I've 
> done it, use a bs=256, in which case the 35 track SS disk would then be the 
> 630 sectors you have in mind.
> 
> Needs more coffee is my guess, Mark.  ;-)

Maybe not...IIRC, the HDB-DOS images (and maybe the OS-9 images?) only
use 256 bytes out of each 512-byte sector.  So the number of sectors
for the images on the CF card is the same as the number of sectors on
a floppy disk, even though the sectors sizes are technically different.
So, 630 is probably the correct number of sectors.

The hdbconv paramter to the Toolshed decb command is used to convert
the 512-byte sectors images that dd gets from the CF card into the
256-byte sector images normally used for DECB-style floppy images.

Hth!

John
-- 
John W. Linville		Someday the world will need a hero, and you
linville at tuxdriver.com			might be all we have.  Be ready.



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