📄 cyclic redundancy codes.htm
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<H1>Cyclic redundancy codes</H1>
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<H2>Using parity some errors are masked - careful choice of bit combinations
can lead to better detection. </H2></UL>
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<H2>CRC codes use bit sequences of 12 -16 bits to check data </H2></UL>
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<H2>CRC-12 = X12 + X 11 + X 3 + X2 + X + 1 </H2></UL>
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<H2>CRC-16 = X16 + X 15 + X2 + 1 </H2></UL>
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<H2>CRC-CCITT = X16 + X 12 + X5 + 1 </H2></UL>
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<H2>operate on data - 12-16 bit check sequences. </H2></UL>
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<H2>Divide data by CRC as 1 0001 0000 0010 0001 </H2></UL>
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<H2>(CRC-CCITT) remainder is Check Sequence (FCS)</H2></UL>
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