MODBUS RTU 通讯协议
一、 通讯协议
本系采用单主多从网络数据通信方式,与 MODBUS RTU 通讯规约相兼容:
波特率: 2400,4800,9600
消息发送至少要以 3.5 个字符时间的停顿间隔作为开始。整个消息帧必须作为连续的数
据流来传送,如果整个数据流在传送完成之前发生超过 3.5 个字符时间的传送停顿,接收设
备将刷新不完整的消息并假定下一字节是一个新消息的地址域;同样地,如果一个新消息在
小于 3.5 个字符时间内接着前个消息开始,接收设备将认为它是前一消息的延续。
一帧信息的标准结构如下所示:
1、地址码:地址码为通讯传送的第一个字节。这个字节表明由用户设定地址码
的从机将接收由主机发送来的信息。并且每个从机都具有唯一的地址码,
并且响应回送均以各自的地址码开始。主机发送的地址码表明将发送到
的从机地址,而从机发送的地址码表明回送的从机地址。 “从机” 的地址
范围为1~128 (十进制) 。
2、功能码:通讯传送的第二个字节。 有效的编码范围是1…255(十进制)。 作为主机
请求发送,通过功能码告诉从机执行什么动作。 例如:
02:读取多位寄存器;
03:读取多字寄存器;
15:写位位寄存器;
16:写多字寄存器;
从机可以响应也可以不响应,作为从机响应,从机发送的功能码与从主机发
送来的功能码一样,并表明从机已响应主机进行操作。可以约定对于广播数据不
作响应。
3、数据区:数据区是根据不同的功能码而不同。数据区可以是实际数值、设置
点、主机发送给从机或从机发送给主机的寄存器地址,连续数据长度等。
4、CRC 码: 低字节在前,高字节在后。
注:本仪表通讯时的读取间隔,在通讯速率等于 9600bps 时, 一般命令的读取间隔建议大于
50mS,0X69(连读)命令大于 250mS。
更多介绍请见附件pdf。
源码如下:
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.IO.Ports;
using System.Text;
using System.Threading;
using Bandweaver.Bus.Data;
namespace Bandweaver.Applet.HaiNanDataAgent
{
/// <summary>
/// 版权(C), 2008-2017, Krones
/// 文件名称:ModbusHelper.cs
/// 编写人员:成杭
/// 编写日期:2016/10/8 13:31:01
/// 功能描述:完成对Modbus操作帮助类
/// 更改历史:
/// </summary>
public class ModbusController
{
#region 事件
/// <summary>
/// 接收数据
/// </summary>
public event RecivedDataEventHandler RecivedDataEvent = null;
/// <summary>
/// 接收到消息
/// </summary>
public event RecivedMessageEventHandler RecivedMessageEvent = null;
/// <summary>
/// COMM口状态改变事件
/// </summary>
public event ComPortStatusChangedEventHandler ComPortStatusChangedEvent = null;
#endregion
#region 属性
/// <summary>
/// 状态
/// </summary>
public AppStatus Status = AppStatus.停止;
/// <summary>
/// COM操作对象
/// </summary>
private SerialPort sp = new SerialPort();
/// <summary>
/// 锁
/// </summary>
private static Object o = new Object();
/// <summary>
/// CRC验证表
/// </summary>
public byte[] crc_table = new byte[512];
/// <summary>
/// 数据集合
/// </summary>
private Dictionary<Int16, Int16> DicData = null;
/// <summary>
/// 从机地址
/// </summary>
private byte SlaveID = 0;
/// <summary>
/// 数据发送对象配置信息
/// </summary>
private ArrayList DataList = null;
/// <summary>
/// COM口配置信息
/// </summary>
private ComSetting Setting = null;
#endregion
#region 构造函数
/// <summary>
/// 构造函数
/// </summary>
public ModbusController(RecivedConfigurationTable configuration)
{
#region 初始化CRC
crc_table[0] = 0x0;
crc_table[1] = 0xC1;
crc_table[2] = 0x81;
crc_table[3] = 0x40;
crc_table[4] = 0x1;
crc_table[5] = 0xC0;
crc_table[6] = 0x80;
crc_table[7] = 0x41;
crc_table[8] = 0x1;
crc_table[9] = 0xC0;
crc_table[10] = 0x80;
crc_table[11] = 0x41;
crc_table[12] = 0x0;
crc_table[13] = 0xC1;
crc_table[14] = 0x81;
crc_table[15] = 0x40;
crc_table[16] = 0x1;
crc_table[17] = 0xC0;
crc_table[18] = 0x80;
crc_table[19] = 0x41;
crc_table[20] = 0x0;
crc_table[21] = 0xC1;
crc_table[22] = 0x81;
crc_table[23] = 0x40;
crc_table[24] = 0x0;
crc_table[25] = 0xC1;
crc_table[26] = 0x81;
crc_table[27] = 0x40;
crc_table[28] = 0x1;
crc_table[29] = 0xC0;
crc_table[30] = 0x80;
crc_table[31] = 0x41;
crc_table[32] = 0x1;
crc_table[33] = 0xC0;
crc_table[34] = 0x80;
crc_table[35] = 0x41;
crc_table[36] = 0x0;
crc_table[37] = 0xC1;
crc_table[38] = 0x81;
crc_table[39] = 0x40;
crc_table[40] = 0x0;
crc_table[41] = 0xC1;
crc_table[42] = 0x81;
crc_table[43] = 0x40;
crc_table[44] = 0x1;
crc_table[45] = 0xC0;
crc_table[46] = 0x80;
crc_table[47] = 0x41;
crc_table[48] = 0x0;
crc_table[49] = 0xC1;
crc_table[50] = 0x81;
crc_table[51] = 0x40;
crc_table[52] = 0x1;
crc_table[53] = 0xC0;
crc_table[54] = 0x80;
crc_table[55] = 0x41;
crc_table[56] = 0x1;
crc_table[57] = 0xC0;
crc_table[58] = 0x80;
crc_table[59] = 0x41;
crc_table[60] = 0x0;
crc_table[61] = 0xC1;
crc_table[62] = 0x81;
crc_table[63] = 0x40;
crc_table[64] = 0x1;
crc_table[65] = 0xC0;
crc_table[66] = 0x80;
crc_table[67] = 0x41;
crc_table[68] = 0x0;
crc_table[69] = 0xC1;
crc_table[70] = 0x81;
crc_table[71] = 0x40;
crc_table[72] = 0x0;
crc_table[73] = 0xC1;
crc_table[74] = 0x81;
crc_table[75] = 0x40;
crc_table[76] = 0x1;
crc_table[77] = 0xC0;
crc_table[78] = 0x80;
crc_table[79] = 0x41;
crc_table[80] = 0x0;
crc_table[81] = 0xC1;
crc_table[82] = 0x81;
crc_table[83] = 0x40;
crc_table[84] = 0x1;
crc_table[85] = 0xC0;
crc_table[86] = 0x80;
crc_table[87] = 0x41;
crc_table[88] = 0x1;
crc_table[89] = 0xC0;
crc_table[90] = 0x80;
crc_table[91] = 0x41;
crc_table[92] = 0x0;
crc_table[93] = 0xC1;
crc_table[94] = 0x81;
crc_table[95] = 0x40;
crc_table[96] = 0x0;
crc_table[97] = 0xC1;
crc_table[98] = 0x81;
crc_table[99] = 0x40;
crc_table[100] = 0x1;
crc_table[101] = 0xC0;
crc_table[102] = 0x80;
crc_table[103] = 0x41;
crc_table[104] = 0x1;
crc_table[105] = 0xC0;
crc_table[106] = 0x80;
crc_table[107] = 0x41;
crc_table[108] = 0x0;
crc_table[109] = 0xC1;
crc_table[110] = 0x81;
crc_table[111] = 0x40;
crc_table[112] = 0x1;
crc_table[113] = 0xC0;
crc_table[114] = 0x80;
crc_table[115] = 0x41;
crc_table[116] = 0x0;
crc_table[117] = 0xC1;
crc_table[118] = 0x81;
crc_table[119] = 0x40;
crc_table[120] = 0x0;
crc_table[121] = 0xC1;
crc_table[122] = 0x81;
crc_table[123] = 0x40;
crc_table[124] = 0x1;
crc_table[125] = 0xC0;
crc_table[126] = 0x80;
crc_table[127] = 0x41;
crc_table[128] = 0x1;
crc_table[129] = 0xC0;
crc_table[130] = 0x80;
crc_table[131] = 0x41;
crc_table[132] = 0x0;
crc_table[133] = 0xC1;
crc_table[134] = 0x81;
crc_table[135] = 0x40;
crc_table[136] = 0x0;
crc_table[137] = 0xC1;
crc_table[138] = 0x81;
crc_table[139] = 0x40;
crc_table[140] = 0x1;
crc_table[141] = 0xC0;
crc_table[142] = 0x80;
crc_table[143] = 0x41;
crc_table[144] = 0x0;
crc_table[145] = 0xC1;
crc_table[146] = 0x81;
crc_table[147] = 0x40;
crc_table[148] = 0x1;
crc_table[149] = 0xC0;
crc_table[150] = 0x80;
crc_table[151] = 0x41;
crc_table[152] = 0x1;
crc_table[153] = 0xC0;
crc_table[154] = 0x80;
crc_table[155] = 0x41;
crc_table[156] = 0x0;
crc_table[157] = 0xC1;
crc_table[158] = 0x81;
crc_table[159] = 0x40;
crc_table[160] = 0x0;
crc_table[161] = 0xC1;
crc_table[162] = 0x81;
crc_table[163] = 0x40;
crc_table[164] = 0x1;
crc_table[165] = 0xC0;
crc_table[166] = 0x80;
crc_table[167] = 0x41;
crc_table[168] = 0x1;
crc_table[169] = 0xC0;
crc_table[170] = 0x80;
crc_table[171] = 0x41;
crc_table[172] = 0x0;
crc_table[173] = 0xC1;
crc_table[174] = 0x81;
crc_table[175] = 0x40;
crc_table[176] = 0x1;
crc_table[177] = 0xC0;
crc_table[178] = 0x80;
crc_table[179] = 0x41;
crc_table[180] = 0x0;
crc_table[181] = 0xC1;
crc_table[182] = 0x81;
crc_table[183] = 0x40;
crc_table[184] = 0x0;
crc_table[185] = 0xC1;
crc_table[186] = 0x81;
crc_table[187] = 0x40;
crc_table[188] = 0x1;
crc_table[189] = 0xC0;
crc_table[190] = 0x80;
crc_table[191] = 0x41;
crc_table[192] = 0x0;
crc_table[193] = 0xC1;
crc_table[194] = 0x81;
crc_table[195] = 0x40;
crc_table[196] = 0x1;
crc_table[197] = 0xC0;
crc_table[198] = 0x80;
crc_table[199] = 0x41;
crc_table[200] = 0x1;
crc_table[201] = 0xC0;
crc_table[202] = 0x80;
crc_table[203] = 0x41;
crc_table[204] = 0x0;
crc_table[205] = 0xC1;
crc_table[206] = 0x81;
crc_table[207] = 0x40;
crc_table[208] = 0x1;
crc_table[209] = 0xC0;
crc_table[210] = 0x80;
crc_table[211] = 0x41;
crc_table[212] = 0x0;
crc_table[213] = 0xC1;
crc_table[214] = 0x81;
crc_table[215] = 0x40;
crc_table[216] = 0x0;
crc_table[217] = 0xC1;
crc_table[218] = 0x81;
crc_table[219] = 0x40;
crc_table[220] = 0x1;
crc_table[221] = 0xC0;
crc_table[222] = 0x80;
crc_table[223] = 0x41;
crc_table[224] = 0x1;
crc_table[225] = 0xC0;
crc_table[226] = 0x80;
crc_table[227] = 0x41;
crc_table[228] = 0x0;
crc_table[229] = 0xC1;
crc_table[230] = 0x81;
crc_table[231] = 0x40;
crc_table[232] = 0x0;
crc_table[233] = 0xC1;
crc_table[234] = 0x81;
crc_table[235] = 0x40;
crc_table[236] = 0x1;
crc_table[237] = 0xC0;
crc_table[238] = 0x80;
crc_table[239] = 0x41;
crc_table[240] = 0x0;
crc_table[241] = 0xC1;
crc_table[242] = 0x81;
crc_table[243] = 0x40;
crc_table[244] = 0x1;
crc_table[245] = 0xC0;
crc_table[246] = 0x80;
crc_table[247] = 0x41;
crc_table[248] = 0x1;
crc_table[249] = 0xC0;
crc_table[250] = 0x80;
crc_table[251] = 0x41;
crc_table[252] = 0x0;
crc_table[253] = 0xC1;
crc_table[254] = 0x81;
crc_table[255] = 0x40;
crc_table[256] = 0x0;
crc_table[257] = 0xC0;
crc_table[258] = 0xC1;
crc_table[259] = 0x1;
crc_table[260] = 0xC3;
crc_table[261] = 0x3;
crc_table[262] = 0x2;
crc_table[263] = 0xC2;
crc_table[264] = 0xC6;
crc_table[265] = 0x6;
crc_table[266] = 0x7;
crc_table[267] = 0xC7;
crc_table[268] = 0x5;
crc_table[269] = 0xC5;
crc_table[270] = 0xC4;
crc_table[271] = 0x4;
crc_table[272] = 0xCC;
crc_table[273] = 0xC;
crc_table[274] = 0xD;
crc_table[275] = 0xCD;
crc_table[276] = 0xF;
crc_table[277] = 0xCF;
crc_table[278] = 0xCE;
crc_table[279] = 0xE;
crc_table[280] = 0xA;
crc_table[281] = 0xCA;
crc_table[282] = 0xCB;
crc_table[283] = 0xB;
crc_table[284] = 0xC9;
crc_table[285] = 0x9;
crc_table[286] = 0x8;
crc_table[287] = 0xC8;
crc_table[288] = 0xD8;
crc_table[289] = 0x18;
crc_table[290] = 0x19;
crc_table[291] = 0xD9;
crc_table[292] = 0x1B;
crc_table[293] = 0xDB;
crc_table[294] = 0xDA;
crc_table[295] = 0x1A;
crc_table[296] = 0x1E;
crc_table[297] = 0xDE;
crc_table[298] = 0xDF;
crc_table[299] = 0x1F;
crc_table[300] = 0xDD;
crc_table[301] = 0x1D;
crc_table[302] = 0x1C;
crc_table[303] = 0xDC;
crc_table[304] = 0x14;
crc_table[305] = 0xD4;
crc_table[306] = 0xD5;
crc_table[307] = 0x15;
crc_table[308] = 0xD7;
crc_table[309] = 0x17;
crc_table[310] = 0x16;
crc_table[311] = 0xD6;
crc_table[312] = 0xD2;
crc_table[313] = 0x12;
crc_table[314] = 0x13;
crc_table[315] = 0xD3;
crc_table[316] = 0x11;
crc_table[317] = 0xD1;
crc_table[318] = 0xD0;
crc_table[319] = 0x10;
crc_table[320] = 0xF0;
crc_table[321] = 0x30;
crc_table[322] = 0x31;
crc_table[323] = 0xF1;
crc_table[324] = 0x33;
crc_table[325] = 0xF3;
crc_table[326] = 0xF2;
crc_table[327] = 0x32;
crc_table[328] = 0x36;
crc_table[329] = 0xF6;
crc_table[330] = 0xF7;
crc_table[331] = 0x37;
crc_table[332] = 0xF5;
crc_table[333] = 0x35;
crc_table[334] = 0x34;
crc_table[335] = 0xF4;
crc_table[336] = 0x3C;
crc_table[337] = 0xFC;
crc_table[338] = 0xFD;
crc_table[339] = 0x3D;
crc_table[340] = 0xFF;
crc_table[341] = 0x3F;
crc_table[342] = 0x3E;
crc_table[343] = 0xFE;
crc_table[344] = 0xFA;
crc_table[345] = 0x3A;
crc_table[346] = 0x3B;
crc_table[347] = 0xFB;
crc_table[348] = 0x39;
crc_table[349] = 0xF9;
crc_table[350] = 0xF8;
crc_table[351] = 0x38;
crc_table[352] = 0x28;
crc_table[353] = 0xE8;
crc_table[354] = 0xE9;
crc_table[355] = 0x29;
crc_table[356] = 0xEB;
crc_table[357] = 0x2B;
crc_table[358] = 0x2A;
crc_table[359] = 0xEA;
crc_table[360] = 0xEE;
crc_table[361] = 0x2E;
crc_table[362] = 0x2F;
crc_table[363] = 0xEF;
crc_table[364] = 0x2D;
crc_table[365] = 0xED;
crc_table[366] = 0xEC;
crc_table[367] = 0x2C;
crc_table[368] = 0xE4;
crc_table[369] = 0x24;
crc_table[370] = 0x25;
crc_table[371] = 0xE5;
crc_table[372] = 0x27;
crc_table[373] = 0xE7;
crc_table[374] = 0xE6;
crc_table[375] = 0x26;
crc_table[376] = 0x22;
crc_table[377] = 0xE2;
crc_table[378] = 0xE3;
crc_table[379] = 0x23;
crc_table[380] = 0xE1;
crc_table[381] = 0x21;
crc_table[382] = 0x20;
crc_table[383] = 0xE0;
crc_table[384] = 0xA0;
crc_table[385] = 0x60;
crc_table[386] = 0x61;
crc_table[387] = 0xA1;
crc_table[388] = 0x63;
crc_table[389] = 0xA3;
crc_table[390] = 0xA2;
crc_table[391] = 0x62;
crc_table[392] = 0x66;
crc_table[393] = 0xA6;
crc_table[394] = 0xA7;
crc_table[395] = 0x67;
crc_table[396] = 0xA5;
crc_table[397] = 0x65;
crc_table[398] = 0x64;
crc_table[399] = 0xA4;
crc_table[400] = 0x6C;
crc_table[401] = 0xAC;
crc_table[402] = 0xAD;
crc_table[403] = 0x6D;
crc_table[404] = 0xAF;
crc_table[405] = 0x6F;
crc_table[406] = 0x6E;
crc_table[407] = 0xAE;
crc_table[408] = 0xAA;
crc_table[409] = 0x6A;
crc_table[410] = 0x6B;
crc_table[411] = 0xAB;
crc_table[412] = 0x69;
crc_table[413] = 0xA9;
crc_table[414] = 0xA8;
crc_table[415] = 0x68;
crc_table[416] = 0x78;
crc_table[417] = 0xB8;
crc_table[418] = 0xB9;
crc_table[419] = 0x79;
crc_table[420] = 0xBB;
crc_table[421] = 0x7B;
crc_table[422] = 0x7A;
crc_table[423] = 0xBA;
crc_table[424] = 0xBE;
crc_table[425] = 0x7E;
crc_table[426] = 0x7F;
crc_table[427] = 0xBF;
crc_table[428] = 0x7D;
crc_table[429] = 0xBD;
crc_table[430] = 0xBC;
crc_table[431] = 0x7C;
crc_table[432] = 0xB4;
crc_table[433] = 0x74;
crc_table[434] = 0x75;
crc_table[435] = 0xB5;
crc_table[436] = 0x77;
crc_table[437] = 0xB7;
crc_table[438] = 0xB6;
crc_table[439] = 0x76;
crc_table[440] = 0x72;
crc_table[441] = 0xB2;
crc_table[442] = 0xB3;
crc_table[443] = 0x73;
crc_table[444] = 0xB1;
crc_table[445] = 0x71;
crc_table[446] = 0x70;
crc_table[447] = 0xB0;
crc_table[448] = 0x50;
crc_table[449] = 0x90;
crc_table[450] = 0x91;
crc_table[451] = 0x51;
crc_table[452] = 0x93;
crc_table[453] = 0x53;
crc_table[454] = 0x52;
crc_table[455] = 0x92;
crc_table[456] = 0x96;
crc_table[457] = 0x56;
crc_table[458] = 0x57;
crc_table[459] = 0x97;
crc_table[460] = 0x55;
crc_table[461] = 0x95;
crc_table[462] = 0x94;
crc_table[463] = 0x54;
crc_table[464] = 0x9C;
crc_table[465] = 0x5C;
crc_table[466] = 0x5D;
crc_table[467] = 0x9D;
crc_table[468] = 0x5F;
crc_table[469] = 0x9F;
crc_table[470] = 0x9E;
crc_table[471] = 0x5E;
crc_table[472] = 0x5A;
crc_table[473] = 0x9A;
crc_table[474] = 0x9B;
crc_table[475] = 0x5B;
crc_table[476] = 0x99;
crc_table[477] = 0x59;
crc_table[478] = 0x58;
crc_table[479] = 0x98;
crc_table[480] = 0x88;
crc_table[481] = 0x48;
crc_table[482] = 0x49;
crc_table[483] = 0x89;
crc_table[484] = 0x4B;
crc_table[485] = 0x8B;
crc_table[486] = 0x8A;
crc_table[487] = 0x4A;
crc_table[488] = 0x4E;
crc_table[489] = 0x8E;
crc_table[490] = 0x8F;
crc_table[491] = 0x4F;
crc_table[492] = 0x8D;
crc_table[493] = 0x4D;
crc_table[494] = 0x4C;
crc_table[495] = 0x8C;
crc_table[496] = 0x44;
crc_table[497] = 0x84;
crc_table[498] = 0x85;
crc_table[499] = 0x45;
crc_table[500] = 0x87;
crc_table[501] = 0x47;
crc_table[502] = 0x46;
crc_table[503] = 0x86;
crc_table[504] = 0x82;
crc_table[505] = 0x42;
crc_table[506] = 0x43;
crc_table[507] = 0x83;
crc_table[508] = 0x41;
crc_table[509] = 0x81;
crc_table[510] = 0x80;
crc_table[511] = 0x40;
#endregion
if (configuration == null || configuration.DataList == null)
return;
DataList = configuration.DataList;
Setting = configuration.ComSetting;
SlaveID = configuration.SlaveID;
#region 填充数据集合
DicData = new Dictionary<short, short>();
foreach (RecivedData data in DataList)
{
DicData.Add(data.Address, 0);
}
#endregion
}
#endregion
#region 打开、关闭COM口
/// <summary>
/// 打开COM口
/// </summary>
/// <param name="portName">COM口名称</param>
/// <param name="baudRate">波特率</param>
/// <param name="dataBits">数据位</param>
/// <param name="parity">奇偶校验位</param>
/// <param name="stopBits">停止位</param>
/// <returns></returns>
public void Start()
{
if (!sp.IsOpen)
{
try
{
sp.PortName = Setting.PortName;
sp.BaudRate = Setting.BaudRate;
sp.DataBits = Setting.DataBits;
sp.Parity = Setting.Parity;
sp.StopBits = Setting.StopBits;
sp.DtrEnable = true;//启用控制终端就续信号
sp.RtsEnable = true; //启用请求发送信号
sp.ReadTimeout = 1000;
sp.WriteTimeout = 1000;
sp.Open();
Status = AppStatus.监听;
sp.DataReceived += new SerialDataReceivedEventHandler(sp_DataReceived);
}
catch
{
Status = AppStatus.停止;
}
}
if (ComPortStatusChangedEvent != null)
{
ComPortStatusChangedEvent(Status);
}
}
/// <summary>
/// 关闭COM口
/// </summary>
/// <returns></returns>
public void Close()
{
if (sp != null)
{
if (sp.IsOpen)
{
try
{
sp.Close();
}
catch
{
}
}
}
Status = AppStatus.停止;
if (ComPortStatusChangedEvent != null)
{
ComPortStatusChangedEvent(Status);
}
}
/// <summary>
/// 刷新指定数据
/// </summary>
public void RefreshData(short address, float value)
{
foreach (RecivedData data in DataList)
{
if (data.Address == address)
{
DicData[address] = (short)(value * (data.ExactNum == 0 ? 1 : data.ExactNum));
break;
}
}
}
#endregion
#region 生成CRC码
/// <summary>
/// 生成CRC码
/// </summary>
/// <param name="message">发送或返回的命令,CRC码除外</param>
/// <param name="CRC">生成的CRC码</param>
public void GetCRC(byte[] message, ref byte[] CRC)
{
ushort CRCFull = 0xFFFF;
byte CRCHigh = 0xFF, CRCLow = 0xFF;
char CRCLSB;
for (int i = 0; i < message.Length - 2; i++)
{
CRCFull = (ushort)(CRCFull ^ message[i]);
for (int j = 0; j < 8; j++)
{
CRCLSB = (char)(CRCFull & 0x0001);
//下面两句所得结果一样
//CRCFull = (ushort)(CRCFull >> 1);
CRCFull = (ushort)((CRCFull >> 1) & 0x7FFF);
if (CRCLSB == 1)
CRCFull = (ushort)(CRCFull ^ 0xA001);
}
}
CRC[1] = CRCHigh = (byte)((CRCFull >> 8) & 0xFF);
CRC[0] = CRCLow = (byte)(CRCFull & 0xFF);
}
#endregion
#region CRC验证
/// <summary>
/// 国标算法
/// </summary>
/// <param name="modbusframe">数据</param>
/// <param name="Length">数据字节长度</param>
/// <returns></returns>
private int crc16(byte[] modbusframe, int Length)
{
int i;
int index;
int crc_Low = 0xFF;
int crc_High = 0xFF;
for (i = 0; i < Length; i++)
{
index = crc_High ^ (char)modbusframe[i];
crc_High = crc_Low ^ crc_table[index];
crc_Low = (byte)crc_table[index + 256];
}
return crc_High * 256 + crc_Low;
}
/// <summary>
/// CRC校验
/// </summary>
/// <param name="src">ST开头,&&结尾</param>
/// <returns>十六进制数</returns>
public string CRCEfficacy(string src)
{
byte[] byteArr = Encoding.UTF8.GetBytes(src);
int len = byteArr.Length;
int temp = crc16(byteArr, len);
string result = temp.ToString("X");
return result;
}
#endregion
#region 数据读取
void sp_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
lock (o)
{
try
{
Thread.Sleep(120);
int len = sp.BytesToRead;
if (len != 0)
{
byte[] buff = new byte[len];
sp.Read(buff, 0, len);
Thread thread = new Thread(new ParameterizedThreadStart(HandData));
thread.Start(buff);
}
}
catch (Exception ex)
{
if (RecivedMessageEvent != null)
{
RecivedMessageEvent(ex.Message);
}
}
}
}
/// <summary>
/// 数据接收线程
/// </summary>
private void HandData(object o)
{
byte[] buff = o as byte[];
if (buff == null)
return;
int crc = crc16(buff, buff.Length);
if (crc != 0)
{
//Crc数据校验失败
string str = string.Empty;
foreach (byte b in buff)
{
str += b + " ";
}
RecivedMessage("Crc校验错误,数据:" + str);
}
if (buff.Length < 8)
return;
ModbusData data = new ModbusData();
data.SlaveID = buff[0];
if (data.SlaveID != SlaveID)//判断是否符合从机地址
{
RecivedMessage("从机地址错误,地址:" + data.SlaveID);
return;
}
data.Code = buff[1];
if (data.Code == 3)
{
RecivedMessage("接收数据请求信息");
#region 响应数据请求
try
{
byte[] temp = new byte[2];//起始地址
temp[0] = buff[3];
temp[1] = buff[2];
Int16 startAddress = BitConverter.ToInt16(temp, 0);//值
temp = new byte[2];//数量
temp[0] = buff[5];
temp[1] = buff[4];
Int16 count = BitConverter.ToInt16(temp, 0);//值
if (count > 0)
{
byte[] response = new byte[2 + 1 + count * 2];
response[0] = data.SlaveID;
response[1] = data.Code;
response[2] = Convert.ToByte(count * 2);
for (Int16 index = 0; index < count; index++)
{
Int16 dataValue = 0;
short key = Convert.ToInt16(startAddress + index);
if (DicData.ContainsKey(key))
{
dataValue = DicData[key];
}
byte[] valueByte = BitConverter.GetBytes(dataValue);
response[3 + index * 2 + 1] = valueByte[0];
response[3 + index * 2] = valueByte[1];
}
byte[] crcBytes = new byte[2];
byte[] sendResponse = new byte[response.Length + crcBytes.Length];
response.CopyTo(sendResponse, 0);
GetCRC(sendResponse, ref crcBytes);
sendResponse[sendResponse.Length - 1] = crcBytes[1];//高8位
sendResponse[sendResponse.Length - 2] = crcBytes[0];//低8位
try
{
sp.Write(sendResponse, 0, sendResponse.Length);
RecivedMessageEvent("数据响应成功,发送数据长度:" + sendResponse.Length + " 数据开始编号:" + startAddress);
}
catch (Exception ex)
{
RecivedMessageEvent("数据响应错误,错误:" + ex.Message + " 数据开始编号:" + startAddress);
}
}
}
catch
{
string str = string.Empty;
foreach (byte b in buff)
{
str += b + " ";
}
RecivedMessage("数据解析错误,数据:" + str);
}
#endregion
}
else
{
//其他命令数据
string str = string.Empty;
foreach (byte b in buff)
{
str += b + " ";
}
RecivedMessage("其他命令数据,数据:" + str);
}
}
/// <summary>
/// 通知消息至前端
/// </summary>
private void RecivedMessage(string message)
{
if (RecivedMessageEvent != null)
{
RecivedMessageEvent(message);
}
}
#endregion
}
#region 委托
/// <summary>
/// 接收到数据信息
/// </summary>
public delegate void RecivedDataEventHandler(ModbusData data);
/// <summary>
/// 接收到告警信息
/// </summary>
public delegate void RecivedMessageEventHandler(string message);
/// <summary>
/// 端口状态改变事件
/// </summary>
public delegate void ComPortStatusChangedEventHandler(AppStatus status);
#endregion
/// <summary>
/// 接收到的数据信息
/// </summary>
public class ModbusData
{
/// <summary>
/// 从机地址
/// </summary>
public byte SlaveID { get; set; }
/// <summary>
/// 功能码
/// </summary>
public byte Code { get; set; }
/// <summary>
/// 数据开始地址
/// </summary>
public Int16 StartAddress { get; set; }
/// <summary>
/// 寄存器个数
/// </summary>
public Int16 MCount { get; set; }
/// <summary>
/// 数值值列表
/// </summary>
public Int16[] Data { get; set; }
}
}
本文转自成杭 51CTO博客,原文链接:http://blog.51cto.com/hangtc/1955689,如需转载请自行联系原作者