C#的modbus的代码怎么写？

先要做就是SOCKET客户端尘李与设备建立连接，认为有一台服务器，开了SOCKET服务在哪里。所以如下代码就水到渠成了。

其中LogHelper代码这里就不写，因为与主题派毕迟无关，如果想运行上面代码的话，注释就行了，这里IP和端口号都是由设备方提供的。真实程序一般都把这两个参数写配置文件中。

设备连数或上以后，下一步当然就是读取数据。Modbus的基本原理就是程序向设备请求，需要读取哪个数据，设备就会返回相应的数据。

//

//******************************************************************************

// CRC 16 Data Table

// *****************

const unsigned int crc_tbl[256]={

0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,

0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,

0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,

0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,

0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,

0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,

0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,

0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,

0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,

0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,

0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,

0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,

0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,

0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,

0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,

0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,

0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,

0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,

0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,

0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,

0x7800, 0xB8C1, 0xb981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,

0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,

0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,

0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,

0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,

0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,

0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,

0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,

0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,

0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,

0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,

0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040}

//#pragma end_abs_address

//******************************************************************************

//

#define DEFAULT_ADDRESS 1// all slaves start with this Modbus address

// communication commands:

//#define CHOOSE_SLOT0x80

//#define POLL_SLOT0x81

//#define POLL_ACK0x82

// positions in a Modbus packet

#define ADDR0

#define FCN 1

#define REGHI 2

#define REGLO3

#define NUMREGSHI 4

#define NUMREGSLO 5

#define OUTBYTES 2

// Modbus exception codes

#define FCN_NOT_SUPPORTED1// a Modbus function code we can't

handle

#define BAD_ADDR_OR_CMD2// a Modbus "register"

(command or address to us) we don't know

#define BAD_COUNT3// num regs != num bytes

* 2

#define CMD_NOT_COMPLETE4// command didn't complete

successfully

// other defines

#define IN0

#define OUT1

//

// SLOT_NUMBER is the 2 byte device configuration

// the first byte is the ID

// the second byte is the transmission mode coded as follows:

//bit 0x01: 0=19200, 1=9600 baud

//bit 0x02: 0=even parity, 1=odd parity

//bit 0x04: 0=parity, 1=no parity

//bit 0x08: 0=1 stop bit, 1=2 stop bits

//if bit 0x04 is set and bit 0x08 is not set then it's 8

bit mode (vs 9 bit mode)

//

//unsigned char receiveBuffer[32] = {0} // Reserve 32 bytes for packet.

unsigned char device_addr = DEFAULT_ADDRESS// assigned device address - start

with disconnected

//unsigned char timeout_counter = 10

//unsigned char timeout_duration = 10 // seconds, default

//unsigned char pkt_index = 0

// return number of bytes in packet, not including crc

unsigned char MDB_get_length(unsigned char in_out, unsigned char* ptr)

{

if(comControlByte &0x20)

return 6

switch(*(ptr+FCN))

{

case 0x06: // write single reg

return 6

case 0x03:// read multiple regs

if (in_out == IN) // incoming packet

return 6

else

return *(ptr+OUTBYTES) + 3

case 0x10:// write multiple regs

return (*(ptr+NUMREGSLO) <<1) + 7

default:// assume error packet

return 3

}

}

// calculate CRC16 on a packet

unsigned int MDB_crc_calc(unsigned char in_out, unsigned char* ptr)

{

unsigned char c1, c2

unsigned int crc = 0xffff

// initial value

unsigned char* ptr_pkt_hdr = ptr

c2 = MDB_get_length(in_out,ptr)

for(c1=0c1<c2c1++)

crc = ((crc >>8) &0xFF) ^ crc_tbl[(crc ^ *ptr_pkt_hdr++) &0xFF]

return crc

}

// check crc on an incoming packet

unsigned char MDB_crc_check(unsigned char* ptr)

{

unsigned int i1

unsigned char c1, c2, c3

i1 = MDB_crc_calc(IN, ptr)

c1 = *(ptr+MDB_get_length(IN,ptr)+1) // msb of incoming crc

c2 = *(ptr+MDB_get_length(IN,ptr)) // lsb of

incoming crc

c3 = (i1 >>8)

// msb of calculated crc

if((c2 == (i1 &0x00FF)) &&(c1 == c3))// compare msb

&lsb

return 1

else

return 0

}

// send Modbus packets

void MDB_pkt_sender(unsigned char* ptr)

{

unsigned char idx, pkt_len

unsigned int i1

// append crc, lsb 1st

i1 = MDB_crc_calc(OUT,ptr)

pkt_len = MDB_get_length(OUT,ptr)

*(ptr+pkt_len++) = (unsigned char)i1 // lsb

*(ptr+pkt_len++) = (i1 >>8) // msb

//SCI1C2 = 0x08 // transmit enable

//comLedOn()

PTGD |= 0x80

for (idx = 0idx <pkt_lenidx++)

{

while(!(SCI1S1 &0x80)) // wait for tdre=1

i1 = SCI1S1

SCI1D = *(ptr+idx)

}

while(!(SCI1S1 &0x80))

while(!(SCI1S1 &0x40))

//comLedOff()

PTGD &= 0x7f

//SCI1C2 = 0x2c // back to receive mode

}

// return a Modbus error packet

void MDB_error(unsigned char exp_code, unsigned char* ptr)

{

*(ptr+FCN) |= 0x80 // set error code

*(ptr+FCN+1) = exp_code // set exception code

MDB_pkt_sender(ptr)

}

//

void MDB_read_data(unsigned char* ptr)

{

if(get_data((ptr+2), *(ptr+3)))

{

// get_data() sticks the length of the data in

receiveBuffer[2]

// receiveBuffer[3] &on will have actual data

// receiveBuffer[0] &receiveBuffer[1] unchanged

MDB_pkt_sender(ptr) // appends CRC before sending

}

else

MDB_error(BAD_ADDR_OR_CMD, ptr)

}

// handle data writes

void MDB_write_data(unsigned char* ptr)

{

if((*(ptr+5)<<1) == *(ptr+6))

{

switch(*(ptr+3))//receiveBuffer[3])

{

//case 0x18:// new timeout value

//timeout_duration = receiveBuffer[7]

//MDB_pkt_sender() // echo

received command

//break

//case 0x63:// lamp test

//clampTest = 40

//MDB_pkt_sender() // echo

received command

//break

case ADDRESS:

//if(receiveBuffer[8] &&

(receiveBuffer[8] <248))// valid addresses

if(*(ptr+8) &&(*(ptr+8) <248))

{

//device_addr = *

(ptr+8)// not until reset

nonvolatile[0] = *(ptr+8)

// device ID

nonvolatile[1] = *(ptr+7)

// transmission mode

nonvolatile[2] =

~nonvolatile[0]

nonvolatile[3] =

~nonvolatile[1]

writeToNonvolatile

(SLOT_NUMBER, &nonvolatile[0])

comControlByte |= 0x20

MDB_pkt_sender(ptr)

comControlByte &= 0xdf

}

else

MDB_error

(BAD_ADDR_OR_CMD, ptr)

break

case INSTALLATION_DATE:// installation

date

readFromNonvolatile(DATE_DATA,

&nonvolatile[0])

nonvolatile[4] = *

(ptr+7)//receiveBuffer[7]

nonvolatile[5] = *

(ptr+8)//receiveBuffer[8]

nonvolatile[6] = *

(ptr+9)//receiveBuffer[9]

nonvolatile[7] = *

(ptr+10)//receiveBuffer[10]

nonvolatile[12] = ~nonvolatile[4]

nonvolatile[13] = ~nonvolatile[5]

nonvolatile[14] = ~nonvolatile[6]

nonvolatile[15] = ~nonvolatile[7]

writeToNonvolatile(DATE_DATA,

&nonvolatile[0])

comControlByte |= 0x20

MDB_pkt_sender(ptr) // echo

received command

comControlByte &= 0xdf

break

default:

MDB_error(BAD_ADDR_OR_CMD, ptr)

break

}

}

else

MDB_error(BAD_COUNT, ptr)

}

//

void MDB_parse(char *bufPtr)

{

unsigned char i = 0

if(MDB_crc_check(bufPtr))

{

if(*(bufPtr+ADDR) == device_addr)

{

switch(*(bufPtr+FCN))

{

case 0x03: // modbus read multiple

regs

MDB_read_data(bufPtr)

break

case 0x10:// modbus write multiple

regs

MDB_write_data(bufPtr)

break

default:// modbus function not

supported

MDB_error

(FCN_NOT_SUPPORTED, bufPtr)

break

}

}

}

}