pic单片机MODBUS协议源代码

#include"My_Config.h" #include"ModBus.h" #include "CRC_IBM_Table.h" ModbusReg_Typ ModbusReg; //Modbus 自定义变量结构体 unsigned char MBCommBuf[MBCommBuf_MAX]; //Modbus Comm Buffer //***********************************Modbus RAM*****************************************************// // ModbusCoil 输出线圈 读写 功能码：01、05、15 // ModbusInput 输入离散量 只读 功能码：02 // ModbusHoldReg 保持寄存器 读写 功能码：03、06、16 // ModbusInputReg 输入寄存器 只读 功能码：04 //******************************************************************************************************// unsigned char ModbusCoil[MBCoil_MAX] = {0}; unsigned char ModbusInput[MBInput_MAX] = {0}; unsigned char ModbusHoldReg[MBHoldReg_MAX] = {0}; unsigned char ModbusInputReg[MBInputReg_MAX] = {0}; //***************************************************************************************** //Modbus 通信先送Hi再送Lo void Modbus_ReadDat() { ModbusInputReg[0] = 0x07; ModbusInputReg[1] = 0xaa; ModbusInputReg[2] = 0x00; ModbusInputReg[3] = 0xff; ModbusInputReg[14] = 0x14; ModbusInputReg[15] = 0x15; } //***************************************************************************************** //CRC_IBM unsigned int CRC_IBM(unsigned char *puchMsg, unsigned short usDataLen) { unsigned char uchCRCHi = 0xFF; unsigned char uchCRCLo = 0xFF; unsigned char uIndex; while(usDataLen--) { uIndex = uchCRCHi ^ *puchMsg++ ; uchCRCHi = uchCRCLo ^ AuchCRCHi[uIndex] ; uchCRCLo = AuchCRCLo[uIndex] ; } return (uchCRCHi << 8 | uchCRCLo); } /*--------------------------从机响应主机询问函数 function code: 03/04 读多个保持寄存器/输入寄存器值-------------------------------------*/ //接收和发送共用CommBuf //询问数据包格式：CommBuf[0] MBCommBuf[1] MBCommBuf[2] MBCommBuf[3] MBCommBuf[4] MBCommBuf[5] MBCommBuf[6] MBCommBuf[7] // MBCommBuf[]={从机地址，功能码，高起始地址，低起始地址，寄存器数高位，寄存器数低位，校验码低位，校验码高位} //响应数据包格式：CommBuf[0] MBCommBuf[1] MBCommBuf[2] MBCommBuf[3] MBCommBuf[4] MBCommBuf[5]…… MBCommBuf[n] // MBCommBuf[]={从机地址，功能码，字节数，数据1，数据2……数据i，校验码低位，校验码高位} /*----------------------------------------------------------------------------------------------------------------------------------------------------*/ void Modbus_ReadRegisters(void) { int16u_Typ CRC_Checksum; if(ModbusReg.ReciveIndex != 8) ModbusReg.State = MODBUS_STATE_START; //非法指令 放弃帧 else if((MBCommBuf[1] == Read_Input_Registers) && (ModbusReg.DataAddress + ModbusReg.DataLength > MBInputReg_MAX)) ModbusReg.State = MODBUS_STATE_START; //读取数据或地址非法 放弃帧 else if((MBCommBuf[1] == Read_Holding_Registers) && (ModbusReg.DataAddress + ModbusReg.DataLength > MBHoldReg_MAX)) ModbusReg.State = MODBUS_STATE_START; //读取数据或地址非法 放弃帧 else { Modbus_ReadDat(); if(MBCommBuf[1] == Read_Holding_Registers) //03 { for (unsigned char i = 0; i < ModbusReg.DataLength; i++) MBCommBuf[3 + i] = ModbusHoldReg[ModbusReg.DataAddress + i]; } else //04 { for (unsigned char i = 0; i < ModbusReg.DataLength; i++) MBCommBuf[3 + i] = ModbusInputReg[ModbusReg.DataAddress + i]; } CRC_Checksum.int16u = CRC_IBM(MBCommBuf,ModbusReg.DataLength + 3); //数据及其前面3个字节需要做CRC运算 MBCommBuf[ModbusReg.DataLength + 3] = CRC_Checksum.int8u[1]; MBCommBuf[ModbusReg.DataLength + 4] = CRC_Checksum.int8u[0]; ModbusReg.SendIndex = ModbusReg.DataLength + 5; ModbusReg.State = MODBUS_STATE_SEND; //跳转发送态 } } //***************************************************************************************** // // //***************************************************************************************** void Modbus_PresetMultipleRegisters(void) { int16u_Typ CRC_Checksum; if(ModbusReg.ReciveIndex == 13) //0x10命令必须是13字节数据 { MBCommBuf[0] = ModbusReg.LocalAddress; CRC_Checksum.int16u = CRC_IBM(MBCommBuf,ModbusReg.DataLength + 3); //数据及其前面3个字节需要做CRC运算 MBCommBuf[ModbusReg.DataLength + 3] = CRC_Checksum.int8u[1]; MBCommBuf[ModbusReg.DataLength + 4] = CRC_Checksum.int8u[0]; MBCommBuf[0] = ModbusReg.LocalAddress; ModbusReg.DataLength = 4; ModbusReg.SendIndex = ModbusReg.DataLength + 5; } else ModbusReg.State = MODBUS_STATE_START; //非法指令 放弃帧 } //***************************************************************************************** //ModBus数据解析 // //***************************************************************************************** void ModBus_Analysis(void) { if(CRC_IBM(MBCommBuf,ModbusReg.ReciveIndex) != 0) //CRC校验错误 放弃帧 跳转起始态 ModbusReg.State = MODBUS_STATE_START; else { ModbusReg.DataAddress = (MBCommBuf[2] << 8) | MBCommBuf[3]; ModbusReg.DataLength = (MBCommBuf[4] << 8) | MBCommBuf[5]; switch(MBCommBuf[1]) { case Read_Coil_Status: break; case Read_Input_Status: break; case Read_Holding_Registers: case Read_Input_Registers: ModbusReg.DataAddress *= 2; ModbusReg.DataLength *= 2; MBCommBuf[2] = ModbusReg.DataLength; Modbus_ReadRegisters(); break; case Preset_Multiple_Registers: ModbusReg.DataAddress *= 2; ModbusReg.DataLength *= 2; MBCommBuf[2] = ModbusReg.DataLength; Modbus_PresetMultipleRegisters(); break; default: ModbusReg.State = MODBUS_STATE_START; //非法指令 放弃帧 break; } } } //***************************************************************************************** //ModBus数据发送 // //***************************************************************************************** void ModBus_Send() { TRSEL = 1; for(unsigned int i = 1000;i > 0;i--); for(unsigned char i = 0;i < ModbusReg.SendIndex;i++) { // Parity_Check(MBCommBuf[i],1); UART_TransmitByte(MBCommBuf[i]); } for(unsigned int i = 1000;i > 0;i--); TRSEL = 0; ModbusReg.TimeCounter = 0; ModbusReg.State = MODBUS_STATE_FINISH; //发送完毕跳转 终止态 } //***************************************************************************************** //ModBus处理 // //***************************************************************************************** void ModBus_Process(void) { if (ModbusReg.State == MODBUS_STATE_PROCESS) //处理态 ModBus_Analysis(); if (ModbusReg.State == MODBUS_STATE_SEND) //发送态 ModBus_Send(); } //***************************************************************************************** //Modbus 初始化 // //***************************************************************************************** void ModBus_Init(void) { ModbusReg.BaudRate = 9600; ModbusReg.ParityMode = Parity