原创 modbus RTU 的C51程序

在网上找到的程序，稍微改了一下就可以用了。

#include "main.h"

int32 dwTickCount,dwIntTick; //时钟
uint8 idata sendBuf[16],receBuf[16]; //发送接收缓冲区
uint8 idata checkoutError; // ==2 偶校验错 
uint8 idata receTimeOut;  //接收超时
uint8 idata c10ms;   //10ms 计时
bit  b1ms,bt1ms,b10ms,bt10ms,b100ms,bt100ms; //定时标志位

// 串行中断程序
void commIntProc() interrupt 4
{
 if(TI)
 {
  TI = 0;
  if(sendPosi < sendCount)
  {
   sendPosi++;
   ACC = sendBuf[sendPosi];
   TB8 = P; //加上校验位
   SBUF = sendBuf[sendPosi];
  }
  else
  {
   b485Send = 0;    //发送完后将485置于接收状态
   receCount = 0;   //清接收地址偏移寄存器
   checkoutError = 0;
  }
 }
 else if(RI)
 {
  RI = 0;
  receTimeOut = 10;    //通讯超时值
  receBuf[receCount] = SBUF;
  ACC = receBuf[receCount];
  if(P != RB8)
   checkoutError = 2; //偶校验出错
  receCount++;          //接收地址偏移寄存器加1
  receCount &= 0x0f;    //最多一次只能接收16个字节
 }

}   // void CommIntProc()

//定时器0 1ms 中断
void timer0IntProc() interrupt 1
{
 TL0 = TIMER_LOW;
    TH0 = TIMER_HIGHT;
    dwIntTick++;
 bt1ms = 1;
    c10ms++;
    if(c10ms >= 10)
    {
        c10ms = 0;      //10ms计时器清零
        bt10ms = 1;
    }
}   // void Timer0IntProc()

//外部中断0
void intEx0Proc(void) interrupt 0
{

}

//计数器1中断
void counter1IntProc(void) interrupt 3 using 1
{

}

//定时处理
void timeProc(void)
{
 static uint8 c200ms;

    bWatchDog = ~ bWatchDog;    //看门狗取反
 b1ms = 0;
 b10ms = 0;
 b100ms = 0;
 
 ET0 = 0;
 dwTickCount = dwIntTick;
 ET0 = 1;

 if(bt1ms)
 {
  bt1ms = 0;
  b1ms = 1;

        if(receTimeOut>0)
        {
            receTimeOut--;
            if(receTimeOut==0 && receCount>0)   //判断通讯接收是否超时
            {
                b485Send = 0;       //将485置为接收状态
                receCount = 0;      //将接收地址偏移寄存器清零
    checkoutError = 0;
            }
        }
 }
 
 if(bt100ms)
 {
  bt100ms = 0;
  b100ms = 1;
 }
    if(bt10ms)      //判断中断10ms标志位是否1
    {
        bt10ms = 0;     //清中断10ms标志位
  b10ms = 1;

        c200ms++;                   //200ms计时器加1
        if(c200ms >= 20)            //判断是否计时到200ms
        {
            c200ms = 0;             //清200ms计时器
            bRunLED = ~bRunLED;     //取反运行指示灯         
        }
    }
}   // void TimerProc(void)

//初始化串口
void initUart(void)
{
 //T2 用于波特率 9600
 T2CON = 0x30;
 RCAP2H = 0xff;
 RCAP2L = 0xb8;
 TR2 = 1;

 //偶校验       
 SCON = 0xd0;
    PCON = 0;
    ES = 1;
}//void initUart(void)

//初始化中断
void initInt(void)
{
 TMOD = 0x51;
 TH0 = TIMER_HIGHT;
 TL0 = TIMER_LOW;
 TR0 = 1; 
    ET0 = 1;
 TH1 = 0;   //9600
    TL1 = 0;
 TR1 = 0;   //定时器1用于计数定时器2用于波特
 ET1 = 1;
 //PT1 = 1;

 IT0 = 1; 
    IT1 = 1;
 EX0 = 0; 
 PX0 = 1;
    EX1 = 0;

 initUart();

 EA = 1;  
}   // void initInt(void)

//初始化
void initProg(void)
{ 
 initInt();
 b485Send = 0;
}

void main(void)
{
 initProg();

 while(1)
 {
  timeProc();
  checkComm0Modbus();
 }
}

#include "main.h"

//字地址 0 - 255 (只取低8位)
//位地址 0 - 255 (只取低8位)

/* CRC 高位字节值表 */
const uint8 code auchCRCHi[] = {
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
} ;
/* CRC低位字节值表*/
const uint8 code auchCRCLo[] = {
0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06,
0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04, 0xCC, 0x0C, 0x0D, 0xCD,
0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09,
0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A,
0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC, 0x14, 0xD4,
0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3,
0x11, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3,
0xF2, 0x32, 0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4,
0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A,
0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, 0x28, 0xE8, 0xE9, 0x29,
0xEB, 0x2B, 0x2A, 0xEA, 0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED,
0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26,
0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60,
0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62, 0x66, 0xA6, 0xA7, 0x67,
0xA5, 0x65, 0x64, 0xA4, 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F,
0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68,
0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA, 0xBE, 0x7E,
0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4, 0x74, 0x75, 0xB5,
0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71,
0x70, 0xB0, 0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92,
0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54, 0x9C, 0x5C,
0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B,
0x99, 0x59, 0x58, 0x98, 0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B,
0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,
0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42,
0x43, 0x83, 0x41, 0x81, 0x80, 0x40
} ;

uint8   testCoil;  //用于测试 位地址1
uint16  testRegister; //用于测试 字址址16

uint8 localAddr = 1; //单片机控制板的地址
uint8 sendCount;  //发送字节个数
uint8 receCount;     //接收到的字节个数
uint8 sendPosi;     //发送位置

uint16 crc16(uint8 *puchMsg, uint16 usDataLen)
{
 uint8 uchCRCHi = 0xFF ; /* 高CRC字节初始化 */
 uint8 uchCRCLo = 0xFF ; /* 低CRC 字节初始化 */
 uint32 uIndex ; /* CRC循环中的索引 */
 while (usDataLen--) /* 传输消息缓冲区 */
 {
  uIndex = uchCRCHi ^ *puchMsg++ ; /* 计算CRC */
  uchCRCHi = uchCRCLo ^ auchCRCHi[uIndex] ;
  uchCRCLo = auchCRCLo[uIndex] ;
 }
 return (uchCRCHi << 8 | uchCRCLo) ;
}//uint16 crc16(uint8 *puchMsg, uint16 usDataLen)

//开始发送
void beginSend(void)
{ 
 b485Send = 1; //设为发送
 
 sendPosi = 0;
 if(sendCount > 1)
  sendCount--;
 ACC = sendBuf[0];
 TB8 = P;
 SBUF = sendBuf[0];

}//void beginSend(void)

//读线圈状态
void readCoil(void)
{
 uint8 addr;
 uint8 tempAddr;
 uint8 byteCount;
 uint8 bitCount;
 uint16 crcData;
 uint8 position;
 uint8 i,k;
 uint8  result;
 uint16 tempData;
 uint8  exit = 0;
 
 //addr = (receBuf[2]<<8) + receBuf[3]; 
 //tempAddr = addr & 0xfff;
 addr = receBuf[3];
 tempAddr = addr;

 //bitCount = (receBuf[4]<<8) + receBuf[5]; //读取的位个数
 bitCount = receBuf[5];

 byteCount = bitCount / 8;     //字节个数
 if(bitCount%8 != 0)
  byteCount++;
         
 for(k=0;k<byteCount;k++)
 {//字节位置
  position = k + 3;
  sendBuf[position] = 0;
  for(i=0;i<8;i++)
  {
   getCoilVal(tempAddr,&tempData);
   
   sendBuf[position] |= tempData << i;
   tempAddr++;
   if(tempAddr >= addr+bitCount)
   { //读完
    exit = 1;
    break;
   } 
  }
  if(exit == 1)
   break;
 }
 
 sendBuf[0] = localAddr;
 sendBuf[1] = 0x01; 
 sendBuf[2] = byteCount;
 byteCount += 3;
 crcData = crc16(sendBuf,byteCount); 
 sendBuf[byteCount] = crcData >> 8;
 byteCount++;
 sendBuf[byteCount] = crcData & 0xff;
 sendCount = byteCount + 1;
 
 beginSend(); 
}//void readCoil(void)

//读寄存器
void readRegisters(void)
{
 uint8 addr;
 uint8 tempAddr;
 uint16 result;
 uint16 crcData;
 uint8 readCount;
 uint8 byteCount;
 uint8  finsh; //1完成  0出错
 uint16 i;
 uint16 tempData = 0; 
 
 //addr = (receBuf[2]<<8) + receBuf[3];
 //tempAddr = addr & 0xfff; 
 addr = receBuf[3];
 tempAddr = addr;

 //readCount = (receBuf[4]<<8) + receBuf[5]; //要读的个数
 readCount = receBuf[5];

 byteCount = readCount * 2;
 
 for(i=0;i<byteCount;i+=2,tempAddr++)
 {
  getRegisterVal(tempAddr,&tempData);    
  sendBuf[i+3] = tempData >> 8;         
  sendBuf[i+4] = tempData & 0xff;   
 }
 
 sendBuf[0] = localAddr;
 sendBuf[1] = 3;
 sendBuf[2] = byteCount;
 byteCount += 3;
 crcData = crc16(sendBuf,byteCount);
 sendBuf[byteCount] = crcData >> 8;
 byteCount++;
 sendBuf[byteCount] = crcData & 0xff;
 
 sendCount = byteCount + 1;
 beginSend();
}//void readRegisters(void)

//强制单个线圈
void forceSingleCoil(void)
{
 uint8 addr;
 uint8 tempAddr;
 uint16 tempData;
 uint8  onOff;
 uint8 i;
 
 //addr = (receBuf[2]<<8) + receBuf[3]; 
 //tempAddr = addr & 0xfff;
 addr = receBuf[3];
 tempAddr = addr;

 //onOff = (receBuf[4]<<8) + receBuf[5]; 
 onOff = receBuf[4];
 
 //if(onOff == 0xff00)
 if(onOff == 0xff)
 { //设为ON
  tempData = 1;
 }
 //else if(onOff == 0x0000)
 else if(onOff == 0x00)
 { //设为OFF
  tempData = 0;
 }

 setCoilVal(tempAddr,tempData); 
 
 for(i=0;i<receCount;i++)
 {
  sendBuf = receBuf;
 }
 sendCount = receCount;
 beginSend(); 
}//void forceSingleCoil(void)