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· Programming
#Misc.
3 messages in this thread
Well sweet sucess!! Here's the info on the header checksum. It is the
encoded longword EOR's of the header starting at the format byte to the end
of the o/s recovery info, then AND with x55555555 to mask out the clock
bits. Andy Finkel was a great deal of help answering my questions about
these checksums. <Glenn
Glenn,
Ok, then if you presume that the "original" header checksum was
0x55555555 and then take the 5 longwords preceeding it and EOR them and then
AND the result with that "original" checksum…you come up with the real
checksum… correct?
It also makes sense to ignore the framing and sync bytes…cause if
they were wrong…you more than likely couldn't read the sector anyway.
I appreciate the information…I've got it tucked away for future
reference…thanks!
Glenn,
Ok, then if you presume that the "original" header checksum was
0x55555555 and then take the 5 longwords preceeding it and EOR them and then
AND the result with that "original" checksum…you come up with the real
checksum… correct?
It also makes sense to ignore the framing and sync bytes…cause if
they were wrong…you more than likely couldn't read the sector anyway.
I appreciate the information…I've got it tucked away for future
reference…thanks!