On Wed, 13 Mar 2002, Ignatios Souvatzis wrote:

: However, this is in terms of block count, where block is what is on the
: disk. For 2-kByte MODs, this would be a range of 32 kBytes.

Although I've yet to see a boot ROM that actually uses 2k blocks -- my test
of setting up a bootable CD (on an A3000 with 40.70 ROM, mind you) made full
use of the 512 byte/block feature of the attached CD drive.  8-)

: > Use of this sector starts at byte 0, length 220.  Magic word `RDSK' at byte
: > 0 to identify it.  Checksum has variable length, so can be made to contain
: > only the RDB.  (sys/arch/amiga/include/disklabel.h:struct rdblock)
:
: every RDB block type is checksummed stand-alone.

Right.  The checksum note is for Luke's info as far as making it possible
for some boot info to overlap (i.e. "we don't have to checksum something
foreign sitting at byte position 400").  Since the RDB header can be
anywhere in the first 16 blocks, it's not particularly important in this
case, but the ability is there to share the RDB header block with something
else.

-- 
-- Todd Vierling <tv@wasabisystems.com>  *  Wasabi & NetBSD:  Run with it.
-- CDs, Integration, Embedding, Support -- http://www.wasabisystems.com/