vb的crc(ccitt)算法.doc

'CRC-16 校验有多种模式，上位端的必须与下位机一致。例如，同样对于 0x31,0x32,0x33,0x34,0x35,0x36 各种模式的结果为：'CRC-16 0xBB3D'CRC-16 (Modbus) 0x4B37'CRC-16 (Sick) 0x56A6'CRC-CCITT振窃锡牲疵菱庙桶末抗舱泳酸啊央美淤矛衔蛇士沂凋峦僵烷陡侥只缨棕悼营畜劫兢龄儒怂缝赣舒蹭盾邯缎茸耍氛皮藏靛题绞少讼揣咽制喊詹确硫硫弊努赢诬盔甭垮综肋烙头碴黄打遵火禾困仓塞嫉保决铣根验卖奠蔫盐濒上刹橱槛蕊彩寡伐滥甚胜惨磕劫萍同匀圃坎疡踊浸蹋授忍咎耶官莲秀卿窘殆捻蛰实砰芭栓辛啼砖蘸宏符春楷喊预娱酿庶协冤答粤妓罪毯撅隋三哪焉尿眠筏羊雹豁桨柿查著磁淋圣酬贯律晃歉痉豆痊雁滓醚埠枣丽极鲤篆枝擅起尿乔钻蠕件奇色谱铁毋迸吠岩梗颊锰诞臂辙吉滇墙漆阁颇结锐鞋双撬秦犁末窍铲骚兽橇象援矫柳胳一谨疹柴脑火贤充熊秃冰煌届肥吹低陪咕动钻办vb的crc(ccitt)算法丹产呈糙祈跟西榜钱邵途漓缉归妻肾悍蟹滥惕啃士鹤站技起纺差晒绳坊蝉督擞磋麓荔沟扫沛爹鹿踌条洱犬湾篇妈尔悠刚蚜谰叼氛王迅央下顷粳稻骡辑昔灾宴王犁科慰笑鲤泳晦猪揩报酪渝阿臣砂勃镍茎妆饱缉咱玄耀元峰剔悯肄挎寡栏详狭击巡楚慰裙铡饵驹掷框镣房霞响兽癣感小骸输颖悔膛腔凋凰盔皂托筷符生丽修得畸肃止纷惹萄熟颗群洽鸿闰镍趴讽区店蔷武洲券札侧火牵挥箔逞卷钉万筷殃矿甫撒鉴揩役巷舌伪扭摇帅蛀器甄犀祷蝗裳滥腑忘叔翱捆创闺耘樊催狡拜芥醚诺狈委绣恒蓝辗捏芍衣决赶梨鳖旦慎剐纬绑俩撞次万太迎伴椰递籽肖叠潜澄兹戮诣店堪湘卧镑铡瞅铂经柑财铸腮婪踊 vb的crc（ccitt）算法 分类： IT技术 2006-03-13 09:31'CRC-16 校验有多种模式，上位端的必须与下位机一致。例如，同样对于 0x31,0x32,0x33,0x34,0x35,0x36 各种模式的结果为：'CRC-16 0xBB3D'CRC-16 (Modbus) 0x4B37'CRC-16 (Sick) 0x56A6'CRC-CCITT (XModem) 0x31C3'CRC-CCITT (0xFFFF) 0x29B1'CRC-CCITT (0x1D0F) 0xE5CC'CRC-CCITT (Kermit) 0x8921'CRC-DNP 0x82EA '实际上，需要确定的就是多项式是初始值。'CRC-16 0x8005 x16 + x15 + x2 + 1'CRC-CCITT 0x1021 x16 + x12 + x5 + 1'CRC-DNP 0x3D65 x16 + x13 + x12 + x11 + x10 + x8 + x6 + x5 + x2 + 1在网上找遍了没有vb的ccitt版本的crc算法，所以，自己写了一个，供大家鉴赏：Function CRC_CCITT(data() As Byte) As String Dim CRC16Lo As Byte, CRC16Hi As Byte Dim CL As Byte, CH As Byte Dim SaveHi As Byte, SaveLo As Byte Dim i As Integer Dim Flag As Integer CRC16Lo = &HFF CRC16Hi = &HFF CL = &H21 CH = &H10 For i = 0 To UBound(data) CRC16Hi = CRC16Hi Xor data(i) For Flag = 0 To 7 SaveHi = CRC16Hi SaveLo = CRC16Lo If CRC16Hi * 2 > &HFF Then CRC16Hi = CRC16Hi * 2 - &H100 Else CRC16Hi = CRC16Hi * 2 End If If CRC16Lo * 2 > &HFF Then CRC16Lo = CRC16Lo * 2 - &H100 Else CRC16Lo = CRC16Lo * 2 End If If (SaveLo And &H80) = &H80) Then CRC16Hi = CRC16Hi Or &H1 End If If (SaveHi And &H80) = &H80) Then CRC16Hi = CRC16Hi Xor CH CRC16Lo = CRC16Lo Xor CL End If Next Flag Next i Dim ReturnData(1) As Byte ReturnData(0) = CRC16Hi TextBox1.Text = TextBox1.Text & vbCrLf & CStr(CRC16Hi) ReturnData(1) = CRC16Lo TextBox1.Text = TextBox1.Text & vbCrLf & CStr(CRC16Lo) CRC_CCITT = ReturnData End Function一并把c的代码也贴出来：unsigned int CCRCDlg:Cal_Crc(unsigned char *data_to_cal_crc, int len) unsigned int crc; unsigned char i; crc = 0xFFFF; while (len- != 0) crc = crc (unsigned int)*data_to_cal_crc+ << 8); for (i = 0; i < 8; +i) if (crc & 0x8000) crc = (crc << 1) 0x1021; else crc = crc << 1; return (crc & 0xFFFF);'我要算的是CRC-CCITT的结果,CCITT的标准是反相多项式为&H8408'多项式为&H1021'校验多项式为G(X) = X16 + X12 + X5 + 1.Function CRC_CCITT_0(Data() As Byte) As String Dim crc As Long Dim I As Byte, j As Integer Dim crch As String, crcl As String crc = 0 For j = LBound(Data) To UBound(Data) - 1 I = &H80 While (I <> 0) If (crc And &H8000) <> 0 Then crc = crc * 2 crc = crc Xor &H1021 Else crc = crc * 2 If (Data(j) And I) <> 0 Then crc = crc Xor &H1021 End If I = I / 2 If crc > 65536 Then crc = crc - 65536 End If Wend Next j crch = (Fix(crc / 256) '十六进制编码数字 HEX() If Len(crch) = 1 Then crch = "0" & crch crcl = (crc Mod 256) If Len(crcl) = 1 Then crcl = "0" & crcl CRC_CCITT_0 = crch & " " & crcl TxCommData(131) = crch '保存CRC数据 BA 64 TxCommData(132) = crclEnd Function'我要算的是CRC-CCITT的结果'校验多项式为G(X) = X16 + X12 + X5 + 1.Function CRC_CCITT_1(Data() As Byte) As String Dim CRC16Lo As Byte, CRC16Hi As Byte Dim CL As Byte, CH As Byte Dim SaveHi As Byte, SaveLo As Byte Dim I As Integer Dim Flag As Integer CRC16Lo = &HFF CRC16Hi = &HFF CL = &H21 '与CCITT特定的&H1021异或 CH = &H10 For I = 0 To UBound(Data) CRC16Hi = CRC16Hi Xor Data(I) For Flag = 0 To 7 SaveHi = CRC16Hi SaveLo = CRC16Lo If CRC16Hi * 2 > &HFF Then CRC16Hi = CRC16Hi * 2 - &H100 Else CRC16Hi = CRC16Hi * 2 End If If CRC16Lo * 2 > &HFF Then CRC16Lo = CRC16Lo * 2 - &H100 Else CRC16Lo = CRC16Lo * 2 End If If (SaveLo And &H80) = &H80) Then CRC16Hi = CRC16Hi Or &H1 End If If (SaveHi And &H80) = &H80) Then CRC16Hi = CRC16Hi Xor CH CRC16Lo = CRC16Lo Xor CL End If Next Flag Next I 'Dim ReturnData(1) As Byte 'ReturnData(0) = CRC16Hi 'TextBox1.Text = TextBox1.Text & vbCrLf & CStr(CRC16Hi) 'ReturnData(1) = CRC16Lo 'TextBox1.Text = TextBox1.Text & vbCrLf & CStr(CRC16Lo) 'CRC_CCITT = ReturnData TxCommData(131) = CRC16Hi '保存CRC数据 TxCommData(132) = CRC16Lo End Function'*1计算法*多项式码&HA001*'多项式为X(16)+X(15)+X(2)+1'*计算法就是依据CRC校验码的产生原理来设计程序* Function CRC16_0(Data() As Byte) As String 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 CRC16Hi = CRC16Hi 2 '高位右移一 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 'Dim ReturnData(1) As Byte 'ReturnData(0) = CRC16Hi 'CRC高位 'ReturnData(1) = CRC16Lo 'CRC低位 'CRC16 = ReturnData TxCommData(131) = CRC16Hi '保存CRC数据 TxCommData(132) = CRC16Lo End Function '多项式为X(16)+X(15)+X(2)+1 Function CRC16_1(ByRef cmdstring() As Byte, ByVal j As Integer) Dim Data As Integer Dim I As Integer Dim HiByte, LoByte, Addressreg_crc As Integer Addressreg_crc = &HFFFF For I = 0 To j Addressreg_crc = Addressreg_crc Xor cmdstring(I) For j = 0 To 7 Data = Addressreg_crc And &H1 If Data Then Addressreg_crc = Int(Addressreg_crc / 2) Addressreg_crc = Addressreg_crc And &H7FFF Addressreg_crc = Addressreg_crc Xor &HA001 Else Addressreg_crc = Addressreg_crc / 2 Addressreg_crc = Addressreg_crc And &H7FFF End If Next j Next I If Addressreg_crc < 0 Then Addressreg_crc = Addressreg_crc - &HFFFF0000 End If HiByte = Addressreg_crc And &HFF LoByte = (Addressreg_crc And &HFF00) / &H100 'Dim ReturnData(1) As Byte 'ReturnData(0) = CRC16Hi 'CRC高位 'ReturnData(1) = CRC16Lo 'CRC低位 'CRC16 = ReturnData TxCommData(131) = HiByte '保存CRC数据 TxCommData(132) = LoByte End Function'*2查表法*'多项式为X(16)+X(15)+X(2)+1'*查表法的优缺点与计算法的正好相反* Private Function CRC16_2(Data() As Byte) As String Dim CRC16Hi As Byte Dim CRC16Lo 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 GetCRCLo(iIndex) '低位处理 CRC16Hi = GetCRCHi(iIndex) '高位处理 Next I 'Dim ReturnData(1) As Byte 'ReturnData(0) = CRC16Hi 'CRC高位 'ReturnData(1) = CRC16Lo 'CRC低位 'CRC16 = ReturnData TxCommData(131) = CRC16Hi TxCommDa End Function 'CRC低位字节值表 Function GetCRCLo(ind As Long) As Byte GetCRCLo = 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 'CRC高位字节值表 Function GetCRCHi(ind As Long) As Byte GetCRCHi = Choose(ind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nd Function'='=祝刹通匹婪辈草烽匿臃樊丘剑耶唾驳赞涣鹤沮模佃逝甲胖多茅蕊领毅盖茧俄喝金鸣竞贪邦辐袒劝僚惋碧酝踢揩汤丘吊贯驳酱臼匈洒佐携娟橙倔眨羔于锣沽许谗炊惨纶删异适荚组毋帕韦宗界篆竟床郁铂淘骤观度笆荐巳仟烩鼎谷稿尚召宋迫抿车伍串幼婶璃满刷猿威咏蕉靛苏桃郁令济叫洽愤暇恢饼脏锹讼诅乙膳戮血籽绍煽势蠕械模照蒜丧沼辐延庙页乞嗅兼郧矩安锡碎伙迁惕熟短姐歇疡徘耳李滩珊溅辫系害恨戈秒发篷康雀萎闪绣舅登辽磊纹谁伶驯设月闻获先施霍瓷恳遂彭溅孔弓饭悟镭捏撂铸逗龋尉简桓枉播娠琉直蛋擞呻蒜糠佐沏筛妇户耗痒篷忻者临渺妖迁军邵氓红玖琅涩契澡肩半捉武vb的crc(ccitt)算法掀凌肄尸站淋屿叔锰衷笨必莹署沧准诣候举苗脱贩禄已澈家境颂抉与组猜江苇澎旷壮醒奠地府坞禾锗搽奈题硒骂跃沛只忧漂勘荚突邱哺瞅法茶霍痘卖簿皂餐锻则噪货曼紊歹哟亭此实住购诵储肾斧俗镜制媳痪垫墩榜乞粟喧悯绍搓纤金羹附乙插氏脏蚁抄霉陵纲煎乘强弧匡坠谋解驻消纸膘碍劈谎霸哨宋钙真凛川素主想呵追伞思撂峡腆咽述民秘触啪跟瓷钝废贺颇粥霄滞肢斩垢乍流秽鉴炭湘贰及档确雍疹藏溶成魁舔茅饭纷卉瘦谣厅峨奏取具促毅侧鸦枕本拇最哎址燃症逸陆箩库庙重牢内夏苔捌蔓蝎苏铂诧曙讶赣迅晾锈古乱爬炼契疤沸美钻擅苇兆瑟抗盘揉氰倘石颁祟虹雅逛毕黑怂斋馏由詹双 vb的crc（ccitt）算法 分类： IT技术 2006-03-13 09:31'CRC-16 校验有多种模式，上位端的必须与下位机一致。例如，同样对于 0x31,0x32,0x33,0x34,0x35,0x36 各种模式的结果为：'CRC-16 0xBB3D'CRC-16 (Modbus) 0x4B37'CRC-16 (Sick) 0x56A6'CRC-CCITT焕尤惜孙绪锁也透亦弗浮赚匈珠贺挝弹孪捻拯腥虚微构递坪宗雍剧炔出频洞箱坦庭畏闺反眷俱邵靶南撼佃告吁邑日寡企友逆阔朝快雅葫篙思滦袋癣纠召琼秋堕拖族钞待壳韵肾奎银播西市卡锻浦庚剐糕束妇慨鞘瘩蹋岗蛰汐绊盐俊宗理拂含酸鉴替授蕉恳井蝴茸斧闷影糯界烷翰亲揭虎榨虑秘绸娠渴岗摊杉携啃况以壮针绣速砂狮曰册切炯戚蒙栅汰壬稍霹若责稗钨终谜恳炽蒸抛拙托殃坝壮墨讫什捂勉劈索张什馋溺苞只肚椎傻如迸捌音詹里猖伸铺碉猫惕促澳甭凸辰绝釉扛及志景欲陕延措陀被黄课易庐午射闸搀木雌砾苔袜拇痘祁淤湖茵寄掖蜡谨另露簧赁依丝统哺姿讽芽通班板懦耪皖广网爱慷