C语言编写modbus协议.docx

C语言编写modbus协议

modbus.c
＃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)
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[i] = receBuf[i];
}
sendCount = receCount;
beginSend();
}//void forceSingleCoil(void)

//设置多个寄存器
void presetMultipleRegisters(void)
{
uint8 addr;
uint8 tempAddr;
uint8 byteCount;
uint8 setCount;
uint16 crcData;
uint16 tempData;
uint8 finsh; //为1时完成 为0时出错
uint8 i;

//addr = (receBuf[2]<<8) + receBuf[3];
//tempAddr = addr & 0xfff;
addr = receBuf[3];
tempAddr = addr & 0xff;

//setCount = (receBuf[4]<<8) + receBuf[5];
setCount = receBuf[5];
byteCount = receBuf[6];

for(i=0;i<setCount;i++,tempAddr++)
{
tempData = (receBuf[i*2+7]<<8) + receBuf[i*2+8];
setRegisterVal(tempAddr,tempData);
}

sendBuf[0] = localAddr;
sendBuf[1] = 16;
sendBuf[2] = addr >> 8;
sendBuf[3] = addr & 0xff;
sendBuf[4] = setCount >> 8;
sendBuf[5] = setCount & 0xff;
crcData = crc16(sendBuf,6);
sendBuf[6] = crcData >> 8;
sendBuf[7] = crcData & 0xff;
sendCount = 8;
beginSend();
}//void presetMultipleRegisters(void)

//检查uart0数据
void checkComm0Modbus(void)
{
uint16 crcData;
uint16 tempData;

if(receCount > 4)
{
switch(receBuf[1])
{
case 1://读取线圈状态(读取点 16位以内)
case 3://读取保持寄存器(一个或多个)
case 5://强制单个线圈
case 6://设置单个寄存器
if(receCount >= 8)
{//接收完成一组数据
//应该关闭接收中断
if(receBuf[0]==localAddr && checkoutError==0)
{
crcData = crc16(receBuf,6);
if(crcData == receBuf[7]+(receBuf[6]<<8))
{//校验正确
if(receBuf[1] == 1)
{//读取线圈状态(读取点 16位以内)
readCoil();
}
else if(receBuf[1] == 3)
{//读取保持寄存器(一个或多个)
readRegisters();
}
else if(receBuf[1] == 5)
{//强制单个线圈
forceSingleCoil();
}
else if(receBuf[1] == 6)
{
//presetSingleRegister();
}

}
}
receCount = 0;
checkoutError = 0;
}
break;
case 15://设置多个线圈
tempData = receBuf[6];
tempData += 9; //数据个数
if(receCount >= tempData)
{
if(receBuf[0]==localAddr && checkoutError==0)
{
crcData = crc16(receBuf,tempData-2);
if(crcData == (receBuf[tempData-2]<<8)+ receBuf[tempData-1])
{
//forceMultipleCoils();
}
}
receCount = 0;
checkoutError = 0;
}
break;

case 16://设置多个寄存器
tempData = (receBuf[4]<<8) + receBuf[5];
tempData = tempData * 2; //数据个数
tempData += 9;
if(receCount >= tempData)
{
if(receBuf[0]==localAddr && checkoutError==0)
{
crcData = crc16(receBuf,tempData-2);
if(crcData == (receBuf[tempData-2]<<8)+ receBuf[tempData-1])
{
presetMultipleRegisters();
}
}
receCount = 0;
checkoutError = 0;
}
break;
default:
break;
}
}
}//void checkComm0(void)

//取线圈状态 返回0表示成功
uint16 getCoilVal(uint16 addr,uint16 *tempData)
{
uint16 result = 0;
uint16 tempAddr;

tempAddr = addr & 0xfff;
//只取低8位地址
switch(tempAddr & 0xff)
{
case 0:
break;
case 1:
*tempData = testCoil;
break;
case 2:
break;
case 3:
break;
case 4:
break;
case 5:
break;
case 6:
break;
case 7:
break;
case 8:
break;
case 9:
break;
case 10:
break;
case 11:
break;
case 12:
break;
case 13:
break;
case 14:
break;
case 15:
break;
case 16:
break;
default:
break;
}

return result;
}//uint16 getCoilVal(uint16 addr,uint16 *data)

//设定线圈状态 返回0表示成功
uint16 setCoilVal(uint16 addr,uint16 tempData)
{
uint16 result = 0;
uint16 tempAddr;

tempAddr = addr & 0xfff;
switch(tempAddr & 0xff)
{
case 0:
break;
case 1:
testCoil = tempData;
break;
case 2:
break;
case 3:
break;
case 4:
break;
case 5:
break;
case 6:
break;
case 7:
break;
case 8:
break;
case 9:
break;
case 10:
break;
case 11:
break;
case 12:
break;
case 13:
break;
case 14:
break;
case 15:
break;
case 16:
break;
default:
break;
}
return result;
}//uint16 setCoilVal(uint16 addr,uint16 data)

//取寄存器值 返回0表示成功
uint16 getRegisterVal(uint16 addr,uint16 *tempData)
{
uint16 result = 0;
uint16 tempAddr;

tempAddr = addr & 0xfff;

switch(tempAddr & 0xff)
{
case 0:
break;
case 1:
break;
case 2:
break;
case 3:
break;
case 4:
break;
case 5:
break;
case 6:
break;
case 7:
break;
case 8:
break;
case 9:
break;
case 10:
break;
case 11:
break;
case 12:
break;
case 13:
break;
case 14:
break;
case 15:
break;
case 16:
*tempData = testRegister;
break;
default:
break;
}

return result;
}//uint16 getRegisterVal(uint16 addr,uint16 &data)

//设置寄存器值 返回0表示成功
uint16 setRegisterVal(uint16 addr,uint16 tempData)
{
uint16 result = 0;
uint16 tempAddr;

tempAddr = addr & 0xfff;

switch(tempAddr & 0xff)
{
case 0:
break;
case 1:
break;
case 2:
break;
case 3:
break;
case 4:
break;
case 5:
break;
case 6:
break;
case 7:
break;
case 8:
break;
case 9:
break;
case 10:
break;
case 11:
break;
case 12:
break;
case 13:
break;
case 14:
break;
case 15:
break;
case 16:
testRegister = tempData;
break;
default:
break;
}

return result;
}//uint8 setRegisterVal(uint16 addr,uint16 data)