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Subject: checksum field (fwd)
From: Björn Stenberg (bjorn_at_haxx.se)
Date: 2001-12-09


Majordomo thought "unscramble" meant "unsubscribe", so this mail ended up in
my mailbox instead of the list.

I've removed this majordomo check.

/Björn

---------- Forwarded message ----------
From: Andy Choi <AndyC_at_CoManage.net>
Subject: checksum field
Date: Sat, 8 Dec 2001 22:04:19 -0500

in case this hasn't already been figured out by others...

bjorn's webpage describes the archos.mof header as including a "16 bit
checksum?".

apparantly, this is is just the 16-bit sum of all the bytes in the
unscrambed code, except with the most significant 4 bits set to 0x4. not
sure what the mask is for, but it seems to work. (i tested this by simply
modifying string constants and seeing that the rescrambled code still passed
the checksum and then correctly displayed the modified strings).



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