ccitt - crc8

[hwsw famulus]

>  Tud nekem küldeni vki egy egyszerû forráskódot?
> -- 
> Best regards,
> György                          mailto:gylab at freestart.hu
> -----------------------------------

Ha ezaz amire gondolsz, akkor

VisualBASIC6-ban van szamolos es tablazatos verziom is...
(Csak herelni kell nehol)

KJ


A fuggvenyes verzio:
-----------------------------------
Function CRC8F(Szoveg)

    Dim CRC As Byte
    Dim J As Byte
    Dim K As Byte
    Dim M As Byte


    '  Szoveg=">?EHP"    CRC=217

    CRC = 0
    For M = 1 To Len(Szoveg)
        x = Asc(Mid(Szoveg, M, 1))
        For K = 0 To 7
            J = 1 And (x Xor CRC)
            CRC = Fix(CRC / 2) And &HFF
            x = Fix(x / 2) And &HFF
            If J <> 0 Then
                CRC = CRC Xor &H8C
            End If
        Next K
    Next

    CRC8F = CRC

End Function
---------------------------


A tablazatos verezio:
----------------------------
Private Sub Command2_Click()

 CRCTable = Array(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, _
 233, 183, 85, 11, 136, 214, 52, 106, 43, 117, 151, 201, 74, 20, 246, 168, _
 116, 42, 200, 150, 21, 75, 169, 247, 182, 232, 10, 84, 215, 137, 107, 53)


    Dim MyCRC As Byte
    Dim I As Integer
    Dim Karakter As String


    '  Szoveg=">?EHP"    CRC=217

        For I = 1 To Len(Szoveg)
            Karakter = Asc(Mid(Szoveg, I, 1))
            MyCRC = CRCTable(MyCRC Xor Karakter)
        Next I

    Text4 = MyCRC

End Sub