[Coco] Cobbler and ERROR 244 on CoCoSDC

Allen Huffman alsplace at pobox.com
Fri Jan 23 21:01:18 EST 2015


Additional comments. I'm thinking out loud here... I used to know RBF so well from all the times I repaired my crashed hard drive using dEd :)  I am hoping this comes back to me as I work through this.

A 128MB disk has:

Sector(s) - Description
---------
$000 - diskID
$001 to $100 - DAM (disk bitmap, 256 bytes with each bit representing a cluster, so 
$101 - File ID sector for root directory
$102 - start of root directory with "." and ".." entries both pointing to $101 :)

When I inspect the DAM (sector 1) on a newly formatted 128MB disk, I see $FFs from $00-$20 and $80 in $21. Since each bit represents a cluster (one sector for a 128MB max image), my drive has the first 41 sectors marked as used.

Does this start with the first root directory sector ($101)? I can't figure out the 41. I would have expected the directory file ID sector plus the length of the directory. Looking at the file ID sector ($101), I see it is a length of $40 (64 bytes). Thats 32 bytes per directory entry ("." and "..", 29 bytes for the file/dir name, then 3 bytes for the LSN of it's file ID sector).

It still looks like the boot track should be available/not used. I just didn't see what I was expecting in the DAM.

		-- A


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