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RE: [ethmac] RX MAC
well this is one way but another way relay on the property of the
CRC that
when you computer the CRCof the data AS WELL AS the CRC field you
should
ALWAYS get the 32FF of the CRC to show the SAME number and this
number is
also called the "magic number".
I don't recall by memorey this number but simple pass the data with
the crc
and see the number you get, than pass another packet and you will be
surprise to see that the result is just the same number :-)
To check an ethernet CRC, feed in the entire packet less the preamble
(but including the checksum), and the resulting value will be the constant
value of 0x2144DF1C (after reflecting and xoring result with all 1's).
one EXTREMLY importent thing but it is also right for the compare
way is
that you always start with the right initial value.
Right, you need to start with all 1's.
- WJ