📄 理解和运用maxim ibutton产品中的循环冗余校验(crc) - maxim.htm
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<TR class=tablebody>
<TD>10001110</TD>
<TD>0 1</TD></TR>
<TR class=tablebodyalt>
<TD>01000111</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>10101111</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>11011011</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>11100001</TD>
<TD>0 8</TD></TR>
<TR class=tablebodyalt>
<TD>11111100</TD>
<TD>1<U> </U></TD></TR>
<TR class=tablebody>
<TD>11110010</TD>
<TD>1</TD></TR>
<TR class=tablebodyalt>
<TD>11110101</TD>
<TD>1</TD></TR>
<TR class=tablebody>
<TD>01111010</TD>
<TD>0 B</TD></TR>
<TR class=tablebodyalt>
<TD>00111101</TD>
<TD>1<U> </U></TD></TR>
<TR class=tablebody>
<TD>00011110</TD>
<TD>1</TD></TR>
<TR class=tablebodyalt>
<TD>10000011</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>11001101</TD>
<TD>0 1</TD></TR>
<TR class=tablebodyalt>
<TD>11101010</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>01110101</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>10110110</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>01011011</TD>
<TD>0 0</TD></TR>
<TR class=tablebodyalt>
<TD>10100001</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>11011100</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>01101110</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>00110111</TD>
<TD>0 0</TD></TR>
<TR class=tablebodyalt>
<TD>10010111</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>11000111</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>11101111</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>11111011</TD>
<TD>0 0</TD></TR>
<TR class=tablebodyalt>
<TD>11110001</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>11110100</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>01111010</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>00111101</TD>
<TD>0 0</TD></TR>
<TR class=tablebodyalt>
<TD>10010010</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>01001001</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>10101000</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>01010100</TD>
<TD>0 0</TD></TR>
<TR class=tablebodyalt>
<TD>00101010</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>00010101</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>10000110</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>01000111</TD>
<TD>0 0</TD></TR>
<TR class=tablebodyalt>
<TD>10101101</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD>11011010</TD>
<TD>0</TD></TR>
<TR class=tablebodyalt>
<TD>01101101</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>10111010</TD>
<TD>0 0</TD></TR>
<TR class=tablebodyalt>
<TD>01011101</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebody>
<TD colSpan=2>10100010 = A2 Hex = CRC Value for
[00000001B81C (Serial Number) + 02 (Family
Code)]</TD></TR>
<TR class=tablebodyalt>
<TD>10100010</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>01010001</TD>
<TD>1</TD></TR>
<TR class=tablebodyalt>
<TD>00101000</TD>
<TD>0 2</TD></TR>
<TR class=tablebody>
<TD>00010100</TD>
<TD>0<U> </U></TD></TR>
<TR class=tablebodyalt>
<TD>00001010</TD>
<TD>0</TD></TR>
<TR class=tablebody>
<TD>00000101</TD>
<TD>1</TD></TR>
<TR class=tablebodyalt>
<TD>00000010</TD>
<TD>0 A</TD></TR>
<TR class=tablebody>
<TD>00000001</TD>
<TD>1<U> </U></TD></TR>
<TR class=tablebodyalt>
<TD colSpan=2>00000000 = 00 Hex = CRC Value for
A2 [(CRC) + 00000001B81C (Serial Number) + 02
(Family
Code)]</TD></TR></TBODY></TABLE><BR><B>例3. DOW
CRC查询函数</B><BR><PRE>Var
CRC : Byte;
Procedure Do_CRC(X: Byte);
{
This procedure calculates the cumulative Maxim 1-Wire CRC of all bytes passed to it.<BR>The result accumulates in the global variable CRC.
}
Const
Table : Array[0..255] of Byte = (
0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65,
157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220,
35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98,
190, 224, 2, 92, 223, 129, 99, 61, 124, 34, 192, 158, 29, 67, 161, 255,
70, 24, 250, 164, 39, 121, 155, 197, 132, 218, 56, 102, 229, 187, 89, 7,
219, 133, 103, 57, 186, 228, 6, 88, 25, 71, 165, 251, 120, 38, 196, 154,
101, 59, 217, 135, 4, 90, 184, 230, 167, 249, 27, 69, 198, 152, 122, 36,
248, 166, 68, 26, 153, 199, 37, 123, 58, 100, 134, 216, 91, 5, 231, 185,
140, 210, 48, 110, 237, 179, 81, 15, 78, 16, 242, 172, 47, 113, 147, 205,
17, 79, 173, 243, 112, 46, 204, 146, 211, 141, 111, 49, 178, 236, 14, 80,
175, 241, 19, 77, 206, 144, 114, 44, 109, 51, 209, 143, 12, 82, 176, 238,
50, 108, 142, 208, 83, 13, 239, 177, 240, 174, 76, 18, 145, 207, 45, 115,
202, 148, 118, 40, 171, 245, 23, 73, 8, 86, 180, 234, 105, 55, 213, 139,
87, 9, 235, 181, 54, 104, 138, 212, 149, 203, 41, 119, 244, 170, 72, 22,
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