VB 的CRC16校验算法 ，转

'Data为字符型数组 start为开始点 size 为几个,返回的即为 CRC

Public Function CRC16(Data() As Byte, start As Integer, size As Integer) As Long

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 size - 1

CRC16Lo = CRC16Lo Xor Data(start + i) '每一个数据与CRC寄存器进行异或

For Flag = 0 To 7

SaveHi = CRC16Hi

SaveLo = CRC16Lo

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

End If

Next Flag

Next i

CRC16 = CRC16Hi 'CRC高位

CRC16 = CRC16 * 256

CRC16 = CRC16 + CRC16Lo 'CRC低位

End Function

查表法：

Private Sub CRC16(data() As Byte)

Dim CRC16Hi As Byte

Dim CRC16Lo As Byte

ReDim ReturnData(2) As Byte

CRC16Hi = &HFF

CRC16Lo = &HFF

Dim i As Integer

Dim iIndex As Long

For i = 0 To UBound(data)

iIndex = CRC16Lo Xor data(i)

CRC16Lo = CRC16Hi Xor GetCRCHi(iIndex) '低位处理

CRC16Hi = GetCRCLo(iIndex) '高位处理

Next i

ReturnData(0) = CRC16Hi 'CRC高位

ReturnData(1) = CRC16Lo 'CRC低位

' For i = 0 To UBound(ReturnData)

' Text9.Text = Text9.Text & Hex(ReturnData(i))

' Next i

Text7.Text = Hex(ReturnData(1))

Text8.Text = Hex(ReturnData(0))

Text9.Text = Hex(ReturnData(1)) & Hex(ReturnData(0))

End Sub

'CRC低位字节值表

Function GetCRCLo(Ind As Long) As Byte

GetCRCLo = Choose(Ind + 1, &H0, &HC0, &HC1, &H1, &HC3, &H3, &H2, &HC2, &HC6, &H6, _

&H7, &HC7, &H5, &HC5, &HC4, &H4, &HCC, &HC, &HD, &HCD, _

&HF, &HCF, &HCE, &HE, &HA, &HCA, &HCB, &HB, &HC9, &H9, _

&H8, &HC8, &HD8, &H18, &H19, &HD9, &H1B, &HDB, &HDA, &H1A, _

&H1E, &HDE, &HDF, &H1F, &HDD, &H1D, &H1C, &HDC, &H14, &HD4, _

&HD5, &H15, &HD7, &H17, &H16, &HD6, &HD2, &H12, &H13, &HD3, _

&H11, &HD1, &HD0, &H10, &HF0, &H30, &H31, &HF1, &H33, &HF3, _

&HF2, &H32, &H36, &HF6, &HF7, &H37, &HF5, &H35, &H34, &HF4, _

&H3C, &HFC, &HFD, &H3D, &HFF, &H3F, &H3E, &HFE, &HFA, &H3A, _

&H3B, &HFB, &H39, &HF9, &HF8, &H38, &H28, &HE8, &HE9, &H29, _

&HEB, &H2B, &H2A, &HEA, &HEE, &H2E, &H2F, &HEF, &H2D, &HED, _

&HEC, &H2C, &HE4, &H24, &H25, &HE5, &H27, &HE7, &HE6, &H26, _

&H22, &HE2, &HE3, &H23, &HE1, &H21, &H20, &HE0, &HA0, &H60, _

&H61, &HA1, &H63, &HA3, &HA2, &H62, &H66, &HA6, &HA7, &H67, _

&HA5, &H65, &H64, &HA4, &H6C, &HAC, &HAD, &H6D, &HAF, &H6F, _

&H6E, &HAE, &HAA, &H6A, &H6B, &HAB, &H69, &HA9, &HA8, &H68, _

&H78, &HB8, &HB9, &H79, &HBB, &H7B, &H7A, &HBA, &HBE, &H7E, _

&H7F, &HBF, &H7D, &HBD, &HBC, &H7C, &HB4, &H74, &H75, &HB5, _

&H77, &HB7, &HB6, &H76, &H72, &HB2, &HB3, &H73, &HB1, &H71, _

&H70, &HB0, &H50, &H90, &H91, &H51, &H93, &H53, &H52, &H92, _

&H96, &H56, &H57, &H97, &H55, &H95, &H94, &H54, &H9C, &H5C, _

&H5D, &H9D, &H5F, &H9F, &H9E, &H5E, &H5A, &H9A, &H9B, &H5B, _

&H99, &H59, &H58, &H98, &H88, &H48, &H49, &H89, &H4B, &H8B, _

&H8A, &H4A, &H4E, &H8E, &H8F, &H4F, &H8D, &H4D, &H4C, &H8C, _

&H44, &H84, &H85, &H45, &H87, &H47, &H46, &H86, &H82, &H42, &H43, &H83, &H41, &H81, &H80, &H40)

End Function

'CRC高位字节值表

Function GetCRCHi(Ind As Long) As Byte

GetCRCHi = Choose(Ind + 1, &H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, &H1, &HC0, _

&H80, &H41, &H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, _

&H0, &HC1, &H81, &H40, &H0, &HC1, &H81, &H40, &H1, &HC0, _

&H80, &H41, &H1, &HC0, &H80, &H41, &H0, &HC1, &H81, &H40, _

&H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, &H0, &HC1, _

&H81, &H40, &H1, &HC0, &H80, &H41, &H1, &HC0, &H80, &H41, _

&H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, &H0, &HC1, _

&H81, &H40, &H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, _

&H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, &H1, &HC0, _

&H80, &H41, &H0, &HC1, &H81, &H40, &H0, &HC1, &H81, &H40, _

&H1, &HC0, &H80, &H41, &H1, &HC0, &H80, &H41, &H0, &HC1, _

&H81, &H40, &H1, &HC0, &H80, &H41, &H0, &HC1, &H81, &H40, _

&H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, &H1, &HC0, _

&H80, &H41, &H0, &HC1, &H81, &H40, &H0, &HC1, &H81, &H40, _

&H1, &HC0, &H80, &H41, &H0, &HC1, &H81, &H40, &H1, &HC0, _

&H80, &H41, &H1, &HC0, &H80, &H41, &H0, &HC1, &H81, &H40, _

&H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, &H1, &HC0, _

&H80, &H41, &H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, _

&H0, &HC1, &H81, &H40, &H0, &HC1, &H81, &H40, &H1, &HC0, _

&H80, &H41, &H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, _

&H1, &HC0, &H80, &H41, &H0, &HC1, &H81, &H40, &H1, &HC0, _

&H80, &H41, &H0, &HC1, &H81, &H40, &H0, &HC1, &H81, &H40, _

&H1, &HC0, &H80, &H41, &H1, &HC0, &H80, &H41, &H0, &HC1, _

&H81, &H40, &H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, _

&H0, &HC1, &H81, &H40, &H1, &HC0, &H80, &H41, &H1, &HC0, &H80, &H41, &H0, &HC1, &H81, &H40)

End Function