reverse-engineering - RS232 データの CRC または CHECKSUM を調べる

Question

RS232 デバイスと通信する必要があります。仕様や情報がありません。

16 バイトのコマンドを送信すると、16 バイトの結果が返されます。最後のバイトは、ある種の crc またはチェックサムのように見えます。このhttp://miscel.dk/MiscEl/miscelCRCandChecksum.htmlを使用してみましたが、うまくいきませんでした。

誰でもcrc/checksumアルゴリズムをリバースエンジニアリングできますか? RS-232 モニタープログラムで取得したデータを次に示します。

01 80 42 00 00 00 00 00 00 00 00 00 00 00 01 B3
01 80 42 00 00 00 00 00 00 00 00 00 00 00 02 51
01 80 42 00 00 00 00 00 00 00 00 00 00 00 03 0F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 04 8C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 05 D2
01 80 42 00 00 00 00 00 00 00 00 00 00 00 06 30
01 80 42 00 00 00 00 00 00 00 00 00 00 00 07 6E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 08 2F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 09 71
01 80 42 00 00 00 00 00 00 00 00 00 00 00 0A 93
01 80 42 00 00 00 00 00 00 00 00 00 00 00 0B CD
01 80 42 00 00 00 00 00 00 00 00 00 00 00 0C 4E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 0D 10
01 80 42 00 00 00 00 00 00 00 00 00 00 00 0E F2
01 80 42 00 00 00 00 00 00 00 00 00 00 00 0F AC
01 80 42 00 00 00 00 00 00 00 00 00 00 00 10 70
01 80 42 00 00 00 00 00 00 00 00 00 00 00 11 2E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 12 CC
01 80 42 00 00 00 00 00 00 00 00 00 00 00 13 92
01 80 42 00 00 00 00 00 00 00 00 00 00 00 14 11
01 80 42 00 00 00 00 00 00 00 00 00 00 00 15 4F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 16 AD
01 80 42 00 00 00 00 00 00 00 00 00 00 00 17 F3
01 80 42 00 00 00 00 00 00 00 00 00 00 00 18 B2
01 80 42 00 00 00 00 00 00 00 00 00 00 00 19 EC
01 80 42 00 00 00 00 00 00 00 00 00 00 00 1A 0E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 1B 50
01 80 42 00 00 00 00 00 00 00 00 00 00 00 1C D3
01 80 42 00 00 00 00 00 00 00 00 00 00 00 1D 8D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 1E 6F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 1F 31
01 80 42 00 00 00 00 00 00 00 00 00 00 00 20 CE
01 80 42 00 00 00 00 00 00 00 00 00 00 00 21 90
01 80 42 00 00 00 00 00 00 00 00 00 00 00 22 72
01 80 42 00 00 00 00 00 00 00 00 00 00 00 23 2C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 24 AF
01 80 42 00 00 00 00 00 00 00 00 00 00 00 25 F1
01 80 42 00 00 00 00 00 00 00 00 00 00 00 26 13
01 80 42 00 00 00 00 00 00 00 00 00 00 00 27 4D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 28 0C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 29 52
01 80 42 00 00 00 00 00 00 00 00 00 00 00 2A B0
01 80 42 00 00 00 00 00 00 00 00 00 00 00 2B EE
01 80 42 00 00 00 00 00 00 00 00 00 00 00 2C 6D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 2D 33
01 80 42 00 00 00 00 00 00 00 00 00 00 00 2E D1
01 80 42 00 00 00 00 00 00 00 00 00 00 00 2F 8F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 30 53
01 80 42 00 00 00 00 00 00 00 00 00 00 00 31 0D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 32 EF
01 80 42 00 00 00 00 00 00 00 00 00 00 00 33 B1
01 80 42 00 00 00 00 00 00 00 00 00 00 00 34 32
01 80 42 00 00 00 00 00 00 00 00 00 00 00 35 6C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 36 8E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 37 D0
01 80 42 00 00 00 00 00 00 00 00 00 00 00 38 91
01 80 42 00 00 00 00 00 00 00 00 00 00 00 39 CF
01 80 42 00 00 00 00 00 00 00 00 00 00 00 3A 2D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 3B 73
01 80 42 00 00 00 00 00 00 00 00 00 00 00 3C F0
01 80 42 00 00 00 00 00 00 00 00 00 00 00 3D AE
01 80 42 00 00 00 00 00 00 00 00 00 00 00 3E 4C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 3F 12
01 80 42 00 00 00 00 00 00 00 00 00 00 00 40 AB
01 80 42 00 00 00 00 00 00 00 00 00 00 00 41 F5
01 80 42 00 00 00 00 00 00 00 00 00 00 00 42 17
01 80 42 00 00 00 00 00 00 00 00 00 00 00 43 49
01 80 42 00 00 00 00 00 00 00 00 00 00 00 44 CA
01 80 42 00 00 00 00 00 00 00 00 00 00 00 45 94
01 80 42 00 00 00 00 00 00 00 00 00 00 00 46 76
01 80 42 00 00 00 00 00 00 00 00 00 00 00 47 28
01 80 42 00 00 00 00 00 00 00 00 00 00 00 48 69
01 80 42 00 00 00 00 00 00 00 00 00 00 00 49 37
01 80 42 00 00 00 00 00 00 00 00 00 00 00 4A D5
01 80 42 00 00 00 00 00 00 00 00 00 00 00 4B 8B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 4C 08
01 80 42 00 00 00 00 00 00 00 00 00 00 00 4D 56
01 80 42 00 00 00 00 00 00 00 00 00 00 00 4E B4
01 80 42 00 00 00 00 00 00 00 00 00 00 00 4F EA
01 80 42 00 00 00 00 00 00 00 00 00 00 00 50 36
01 80 42 00 00 00 00 00 00 00 00 00 00 00 51 68
01 80 42 00 00 00 00 00 00 00 00 00 00 00 52 8A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 53 D4
01 80 42 00 00 00 00 00 00 00 00 00 00 00 54 57
01 80 42 00 00 00 00 00 00 00 00 00 00 00 55 09
01 80 42 00 00 00 00 00 00 00 00 00 00 00 56 EB
01 80 42 00 00 00 00 00 00 00 00 00 00 00 57 B5
01 80 42 00 00 00 00 00 00 00 00 00 00 00 58 F4
01 80 42 00 00 00 00 00 00 00 00 00 00 00 59 AA
01 80 42 00 00 00 00 00 00 00 00 00 00 00 5A 48
01 80 42 00 00 00 00 00 00 00 00 00 00 00 5B 16
01 80 42 00 00 00 00 00 00 00 00 00 00 00 5C 95
01 80 42 00 00 00 00 00 00 00 00 00 00 00 5D CB
01 80 42 00 00 00 00 00 00 00 00 00 00 00 5E 29
01 80 42 00 00 00 00 00 00 00 00 00 00 00 5F 77
01 80 42 00 00 00 00 00 00 00 00 00 00 00 60 88
01 80 42 00 00 00 00 00 00 00 00 00 00 00 61 D6
01 80 42 00 00 00 00 00 00 00 00 00 00 00 62 34
01 80 42 00 00 00 00 00 00 00 00 00 00 00 63 6A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 64 E9
01 80 42 00 00 00 00 00 00 00 00 00 00 00 65 B7
01 80 42 00 00 00 00 00 00 00 00 00 00 00 66 55
01 80 42 00 00 00 00 00 00 00 00 00 00 00 67 0B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 68 4A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 69 14
01 80 42 00 00 00 00 00 00 00 00 00 00 00 6A F6
01 80 42 00 00 00 00 00 00 00 00 00 00 00 6B A8
01 80 42 00 00 00 00 00 00 00 00 00 00 00 6C 2B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 6D 75
01 80 42 00 00 00 00 00 00 00 00 00 00 00 6E 97
01 80 42 00 00 00 00 00 00 00 00 00 00 00 6F C9
01 80 42 00 00 00 00 00 00 00 00 00 00 00 70 15
01 80 42 00 00 00 00 00 00 00 00 00 00 00 71 4B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 72 A9
01 80 42 00 00 00 00 00 00 00 00 00 00 00 73 F7
01 80 42 00 00 00 00 00 00 00 00 00 00 00 74 74
01 80 42 00 00 00 00 00 00 00 00 00 00 00 75 2A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 76 C8
01 80 42 00 00 00 00 00 00 00 00 00 00 00 77 96
01 80 42 00 00 00 00 00 00 00 00 00 00 00 78 D7
01 80 42 00 00 00 00 00 00 00 00 00 00 00 79 89
01 80 42 00 00 00 00 00 00 00 00 00 00 00 7A 6B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 7B 35
01 80 42 00 00 00 00 00 00 00 00 00 00 00 7C B6
01 80 42 00 00 00 00 00 00 00 00 00 00 00 7D E8
01 80 42 00 00 00 00 00 00 00 00 00 00 00 7E 0A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 7F 54
01 80 42 00 00 00 00 00 00 00 00 00 00 00 80 61
01 80 42 00 00 00 00 00 00 00 00 00 00 00 81 3F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 82 DD
01 80 42 00 00 00 00 00 00 00 00 00 00 00 83 83
01 80 42 00 00 00 00 00 00 00 00 00 00 00 84 00
01 80 42 00 00 00 00 00 00 00 00 00 00 00 85 5E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 86 BC
01 80 42 00 00 00 00 00 00 00 00 00 00 00 87 E2
01 80 42 00 00 00 00 00 00 00 00 00 00 00 88 A3
01 80 42 00 00 00 00 00 00 00 00 00 00 00 89 FD
01 80 42 00 00 00 00 00 00 00 00 00 00 00 8A 1F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 8B 41
01 80 42 00 00 00 00 00 00 00 00 00 00 00 8C C2
01 80 42 00 00 00 00 00 00 00 00 00 00 00 8D 9C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 8E 7E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 8F 20
01 80 42 00 00 00 00 00 00 00 00 00 00 00 90 FC
01 80 42 00 00 00 00 00 00 00 00 00 00 00 91 A2
01 80 42 00 00 00 00 00 00 00 00 00 00 00 92 40
01 80 42 00 00 00 00 00 00 00 00 00 00 00 93 1E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 94 9D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 95 C3
01 80 42 00 00 00 00 00 00 00 00 00 00 00 96 21
01 80 42 00 00 00 00 00 00 00 00 00 00 00 97 7F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 98 3E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 99 60
01 80 42 00 00 00 00 00 00 00 00 00 00 00 9A 82
01 80 42 00 00 00 00 00 00 00 00 00 00 00 9B DC
01 80 42 00 00 00 00 00 00 00 00 00 00 00 9C 5F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 9D 01
01 80 42 00 00 00 00 00 00 00 00 00 00 00 9E E3
01 80 42 00 00 00 00 00 00 00 00 00 00 00 9F BD
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A0 42
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A1 1C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A2 FE
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A3 A0
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A4 23
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A5 7D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A6 9F
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A7 C1
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A8 80
01 80 42 00 00 00 00 00 00 00 00 00 00 00 A9 DE
01 80 42 00 00 00 00 00 00 00 00 00 00 00 AA 3C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 AB 62
01 80 42 00 00 00 00 00 00 00 00 00 00 00 AC E1
01 80 42 00 00 00 00 00 00 00 00 00 00 00 AD BF
01 80 42 00 00 00 00 00 00 00 00 00 00 00 AE 5D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 AF 03
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B0 DF
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B1 81
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B2 63
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B3 3D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B4 BE
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B5 E0
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B6 02
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B7 5C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B8 1D
01 80 42 00 00 00 00 00 00 00 00 00 00 00 B9 43
01 80 42 00 00 00 00 00 00 00 00 00 00 00 BA A1
01 80 42 00 00 00 00 00 00 00 00 00 00 00 BB FF
01 80 42 00 00 00 00 00 00 00 00 00 00 00 BC 7C
01 80 42 00 00 00 00 00 00 00 00 00 00 00 BD 22
01 80 42 00 00 00 00 00 00 00 00 00 00 00 BE C0
01 80 42 00 00 00 00 00 00 00 00 00 00 00 BF 9E
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C0 27
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C1 79
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C2 9B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C3 C5
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C4 46
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C5 18
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C6 FA
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C7 A4
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C8 E5
01 80 42 00 00 00 00 00 00 00 00 00 00 00 C9 BB
01 80 42 00 00 00 00 00 00 00 00 00 00 00 CA 59
01 80 42 00 00 00 00 00 00 00 00 00 00 00 CB 07
01 80 42 00 00 00 00 00 00 00 00 00 00 00 CC 84
01 80 42 00 00 00 00 00 00 00 00 00 00 00 CD DA
01 80 42 00 00 00 00 00 00 00 00 00 00 00 CE 38
01 80 42 00 00 00 00 00 00 00 00 00 00 00 CF 66
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D0 BA
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D1 E4
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D2 06
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D3 58
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D4 DB
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D5 85
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D6 67
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D7 39
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D8 78
01 80 42 00 00 00 00 00 00 00 00 00 00 00 D9 26
01 80 42 00 00 00 00 00 00 00 00 00 00 00 DA C4
01 80 42 00 00 00 00 00 00 00 00 00 00 00 DB 9A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 DC 19
01 80 42 00 00 00 00 00 00 00 00 00 00 00 DD 47
01 80 42 00 00 00 00 00 00 00 00 00 00 00 DE A5
01 80 42 00 00 00 00 00 00 00 00 00 00 00 DF FB
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E0 04
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E1 5A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E2 B8
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E3 E6
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E4 65
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E5 3B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E6 D9
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E7 87
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E8 C6
01 80 42 00 00 00 00 00 00 00 00 00 00 00 E9 98
01 80 42 00 00 00 00 00 00 00 00 00 00 00 EA 7A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 EB 24
01 80 42 00 00 00 00 00 00 00 00 00 00 00 EC A7
01 80 42 00 00 00 00 00 00 00 00 00 00 00 ED F9
01 80 42 00 00 00 00 00 00 00 00 00 00 00 EE 1B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 EF 45
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F0 99
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F1 C7
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F2 25
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F3 7B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F4 F8
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F5 A6
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F6 44
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F7 1A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F8 5B
01 80 42 00 00 00 00 00 00 00 00 00 00 00 F9 05
01 80 42 00 00 00 00 00 00 00 00 00 00 00 FA E7
01 80 42 00 00 00 00 00 00 00 00 00 00 00 FB B9
01 80 42 00 00 00 00 00 00 00 00 00 00 00 FC 3A
01 80 42 00 00 00 00 00 00 00 00 00 00 00 FD 64
01 80 42 00 00 00 00 00 00 00 00 00 00 00 FE 86
01 80 42 00 00 00 00 00 00 00 00 00 00 00 FF D8

最後から2番目のバイトは、FFに達すると00から始まる連番のようです。crc/checksum メソッドを推測しやすくするために、00 から FF までの範囲全体を含めました。

コメントを追加できないので、ここに情報を追加します。

前の 15 バイトがすべて等しい場合、最後のバイトは同じです。これはデバイスです: http://www.intelektron.com/productos/tya_rei4000.htm

訂正 (そして、ソフトウェアにバグを見つけたと思います) デバイス自体は、最後から 2 番目のバイトで FF に達した後、00 から開始しますが、デバイスにコマンドを送信するソフトウェアは、FF に達すると 01 から開始します。とにかく、この最後から 2 番目のシーケンスバイトは、crc/checksum の問題とは関係がないと思います。

明確化記載されているデータはソフトウェアによって送信されたコマンドであり、デバイスによる応答は記載されていません。デバイスは、上記の各コマンドに応答して、次のような格納されたデータの 1 行を送信します。

80 01 C2 80 85 01 25 65 57 37 19 32 01 04 76 17

この行には 4 バイトのカード番号、時刻と日付などが含まれていますが、crc/checksum の問題とは関係ないと思います。

追加情報：

私はソフトウェアの VB6 ocxs を調べていて、これを得ました:

Object: clsCRC8
Object: basComunicaciones2
Private sub Proc_1_0_30305330
  loc_30305352: var_8 = 30301198h
  loc_30305373: call basComunicaciones2.SetPropA(edi, arg_8, ebx)
  loc_30305376: var_4 = 0
End Sub

Private sub Proc_1_1_303053A0
  loc_303053C2: var_8 = 303011A0h
  loc_303053E2: call MSVBVM60.DLL.__vbaBoolVarNull(basComunicaciones2.Caption = %x1, arg_8, ebx)
  loc_303053EB: If MSVBVM60.DLL.__vbaBoolVarNull(basComunicaciones2.Caption <> %x1 <>  arg_8 Then GoTo loc_303054B8
  loc_303053F7: var_24 = FFFFFFFFh
  loc_303053FE: var_2C = 11
  loc_30305405: ecx = True
  loc_3030540D: call MSVBVM60.DLL.__vbaUI1I2
  loc_3030541C: edx = edx - 0001h
  loc_30305429: If edx-0001h < 0 Then GoTo loc_30305499
  loc_3030542B: 
  loc_30305443: di = di - basComunicaciones2.%x1 = GetIDsOfNames(%x2) 'Ignore this
  loc_30305447: If di < Me.GetTypeInfo Then GoTo loc_3030544F
  loc_30305449: Err.Raise
  loc_3030544F: 
  loc_30305451: GoTo loc_30305459
  loc_30305453: Err.Raise
  loc_30305459: 
  loc_3030546B: eax = "" And 000000FFh
  loc_30305478: If ecx+eax xor eax < 257 Then GoTo loc_30305480
  loc_3030547A: Err.Raise
  loc_30305480: 
  loc_30305492: var_18 = Var_Ret_1
  loc_30305495: If edi <= Me = %x1 Then GoTo loc_3030542B
  loc_30305499: 
  loc_3030549F: not al
  loc_303054A1: var_18 = Var_Ret_1
  loc_303054A4: var_24 = 0
  loc_303054AB: var_2C = 11
  loc_303054B2: ecx =
  loc_303054B8: 
  loc_303054DC: Exit Sub
End Sub

Private sub Proc_1_2_30306410
  loc_30306432: var_8 = 303011A8h
  loc_3030644F: var_38 = &H4011
  loc_30306489: If Len(Hex()) >= 2 Then GoTo loc_303064A1
  loc_3030649F: var_18 = 808463756 & var_18
  loc_303064A1: 
  loc_303064A6: GoTo loc_303064C1
  loc_303064C0: Exit Sub
  loc_303064C1: 
End Sub

私はこれがデータのCRC8を計算することを確信しています：

メソッド Calcular(Paquete As , CantidadDeBytes As Integer) As Unsigned Small Integer vbpComunicaciones2 のメンバー (cached).clsCRC8 インターフェイス _clsCRC8 で定義

誰でもこのことから何らかの意味を理解できますか? 残念ながら、できません。

score 4 · Accepted Answer

答えはここにありました：http：//blog.sina.com.cn/s/blog_5a1d5bca0100bjvx.html

0xff-上記のリンクからのアルゴリズムの結果であり、すべてが一致します。2日の午後、私がここで得た助けを借りましたが、ついにそれを釘付けにしました。

もちろん、Gerhardによって投稿されたリンクのおかげで、そのコードが何をしているのかを多かれ少なかれ理解しています。ありがとうございました。

score 4 · Accepted Answer

チェックサムやデータ XOR ではありません。
試すことができる CRC オプションがいくつかあります。あなたが提供するデータは、簡単なcrcソリューションで肯定的な結果をもたらしません.

一般的な 8 ビット CRC は次
のとおり
です
。 x8 + x5 + x4 + 1 : 0x31 / 0x8C / 0x98
CRC-8 : x8 + x7 + x6 + x4 + x2 + 1 : 0xD5 / 0xAB / 0xEA
CRC-8-SAE : x8 + x4 + x3 + x2 + 1 : 0x1D / 0xB8 / 0x8E
CRC-8-WCDMA : x8 + x7 + x4 + x3 + x + 1 0x9B / 0xD9 / 0xCD

それを混同するための実装オプションは次のようになります:
通常または逆のデータバイト、初期値 (0xff または 0x00)、ない場合の最終 XOR、および最終 XOR の前の逆 CRC 結果。

CRC の場合、独自にロールしない限り、これらのオプションのオンにする必要があります。

詳細については、CRC エラー検出アルゴリズムの簡単なガイドを参照してください。

score 0 · Accepted Answer

#Define CRCTBL1 0h005EBCE2613FDD83C29C7E20A3FD1F419DC3217FFCA2401E5F01E3BD3E6082DC
#Define CRCTBL2 0h237D9FC1421CFEA0E1BF5D0380DE3C62BEE0025CDF81633D7C22C09E1D43A1FF
#Define CRCTBL3 0h4618FAA427799BC584DA3866E5BB5907DB856739BAE406581947A5FB7826C49A
#Define CRCTBL4 0h653BD987045AB8E6A7F91B45C6987A24F8A6441A99C7257B3A6486D85B05E7B9
#Define CRCTBL5 0h8CD2306EEDB3510F4E10F2AC2F7193CD114FADF3702ECC92D38D6F31B2EC0E50
#Define CRCTBL6 0hAFF1134DCE90722C6D33D18F0C52B0EE326C8ED0530DEFB1F0AE4C1291CF2D73
#Define CRCTBL7 0hCA947628ABF517490856B4EA6937D58B5709EBB536688AD495CB2977F4AA4816
#Define CRCTBL8 0hE9B7550B88D6346A2B7597C94A14F6A8742AC896154BA9F7B6E80A54D7896B35
#Define CRCTBL0 CRCTBL1+CRCTBL2+CRCTBL3+CRCTBL4+CRCTBL5+CRCTBL6+CRCTBL7+CRCTBL8


Lparameters pcString

Local ;
    lnCRC8, ;
    lnIndex, ;
    lnx, ;
    lnByte

m.lnCRC8 = 0

For lnx = 1 To Len(m.pcString)
    m.lnByte  = Asc(Substr(m.pcString, m.lnx, 1))
    m.lnIndex = Bitxor(m.lnCRC8, m.lnByte)
    m.lnCRC8  = Asc(Substr(CRCTBL0, m.lnIndex + 1, 1))
Endfor

m.lnCRC8 = 0xff - m.lnCRC8

Return m.pcString + Chr(m.lnCRC8)

reverse-engineering - RS232 データの CRC または CHECKSUM を調べる

3 に答える 3

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