循环冗余码校验原理分析..
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Dim CRC16Lo As Byte, CRC16Hi As Byte 'CRC寄存器 Dim CL As Byte, CH As Byte '多项式码&HA001 Dim SaveHi As Byte, SaveLo As Byte Dim i As Integer Dim Flag As Integer CRC16Lo = &HFF CRC16Hi = &HFF CL = &H1 CH = &HA0 For i = 0 To UBound(data) CRC16Lo = CRC16Lo Xor data(i) '每一个数据与CRC寄存器进行异或 For Flag = 0 To 7 SaveHi = CRC16Hi SaveLo = CRC16Lo PLC CRC16Hi = CRC16Hi \ 2 '高位右移一位 CRC16Lo = CRC16Lo \ 2 '低位右移一位 If ((SaveHi And &H1) = &H1) Then '如果高位字节最后一位为1 CRC16Lo = CRC16Lo Or &H80 '则低位字节右移后前面补1 End If '否则自动补0 If ((SaveLo And &H1) = &H1) Then '如果LSB为1,则与多项式码进行异或 CRC16Hi = CRC16Hi Xor CH CRC16Lo = CRC16Lo Xor CL上一页 [1] [2] [3] 下一页
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