modbus_master.c

一个modbus 的主机源代码

#define READ_COIL     01
#define READ_DI       02
#define READ_HLD_REG  03
#define READ_AI       04
#define SET_COIL      05
#define SET_HLD_REG  06
#define READ_FIFO     24
#define PROTOCOL_EXCEPTION 0x81
#define PROTOCOL_ERR  1
#define FRM_ERR       2
//unsigned char tx_buf[256],rx_buf[256];
 
const unsigned char 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
} ;

const unsigned  char 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
} ;


const unsigned char char_tab[128]=
             {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,                       
             0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,                      
             0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,                       
             0,1,2,3,4,5,6,7,8,9,0,0,0,0,0,0,                      
             0,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f,0,0,0,0,0,0,0,0,0,    
             0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,                      
             0,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f,0,0,0,0,0,0,0,0,0,    
             0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0                        
              };
const unsigned char tab_char[16]=
{ '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'} ;

unsigned short crc(unsigned char *puchMsg , unsigned short usDataLen)
{
   unsigned char uchCRCHi = 0xFF ; /* high byte of CRC initialized */
   unsigned char uchCRCLo = 0xFF ; /* low byte of CRC initialized */
   unsigned uIndex ; /* will index into CRC lookup table */
   while (usDataLen--)/* pass through message buffer */
   {
 
   
     uIndex = uchCRCHi ^ *puchMsg++ ; /* calculate the CRC */
     uchCRCHi = uchCRCLo ^ auchCRCHi[uIndex];
     uchCRCLo = auchCRCLo[uIndex] ;
   }
  return (uchCRCHi << 8 | uchCRCLo) ;
}

unsigned char a2toh(unsigned char *str)
{
   unsigned char tmp;
   tmp=0;
   tmp=char_tab[*str];
   str++;
   tmp=tmp*16 + char_tab[* str];
   return tmp;

}

int get_bit( unsigned  int data,int bit )
{
const unsigned int bit_tab[]=
{
0x1,0x2,0x4,0x8,0x10,0x20,0x40,0x80,
0x100,0x200,0x400,0x800,0x1000,0x2000,0x4000,0x8000
};

 if (bit >16) return 0;
 if (data & bit_tab[bit]) return 1;
 else return 0;

}

void htoa(  char *str,unsigned char num)//十六进制转换为ASCII码
{
    unsigned char tmp;
    tmp=num; 
    tmp=tmp &0xf0;
    tmp>>=4;
    *str= tab_char [ tmp];
    str++;
    *str= tab_char [ num &0x0f];

}

int  asctortu( unsigned char *dest,unsigned char *source)
{
   unsigned char *tmp;
   unsigned char i;
   i=0;
   tmp=dest;
   if( *source !=':') return 0;
    source ++;
   
   while ( *source !=0x0d)
   {
   *tmp=a2toh( source);
   tmp ++;
   source ++;
   source ++;
   i++;
   }
   source ++;
   if ( *source !=0x0a) return 0;
   else {
         return i;
        }
}
void rtutoascii( unsigned char *dest,unsigned char *source,int lenth)

{
     dest ++;
         
     for ( ; lenth>0;lenth--)
     { 
         htoa( dest,*source);
         dest++;
         dest++;
         source++;
 
         
     }   

}
void rtutoasc( unsigned char *dest,unsigned char *source,int lenth)

{
     dest ++;
         
     for ( ; lenth>0;lenth--)
     { 
         htoa( dest,*source);
         dest++;
         dest++;
         source++;
 

     }   

}


unsigned char lrc(unsigned char *str,int lenth)
{
  unsigned char tmp;
  tmp=0;
  while (lenth-- )
   {
   tmp+= *str++;
 
     
   }
    
 return ((unsigned char)(-((char)tmp)));

}

void construct_ascii_frm ( unsigned char *dst_buf,unsigned char *src_buf,unsigned char lenth)
{
unsigned char lrc_tmp;
lrc_tmp= lrc( src_buf,lenth);
*(src_buf+lenth)=lrc_tmp;
lenth++;
*dst_buf=':';
rtutoascii ( dst_buf,src_buf,lenth);
*(dst_buf+2 * lenth)=0x0d;
*(dst_buf+2 * lenth+1)=0x0a;
}

void construct_rtu_frm ( unsigned char *dst_buf,unsigned char *src_buf,unsigned char lenth)
{
unsigned short  crc_tmp;
crc_tmp= crc( src_buf,lenth);
*(src_buf+lenth)=crc_tmp >>8 ;
*(src_buf+lenth+1)=crc_tmp & 0xff;
lenth++;lenth++;
 
 while ( lenth--)
   { 
   
   *dst_buf=*src_buf;
   dst_buf++;
   src_buf++;	
 	
   }
}
/*
1 读取继电器状态
发送：
*/
int ascii_read_coil_status ( unsigned char board_adr,unsigned char *com_buf,int start_address,int lenth) 

{
unsigned char tmp[256],tmp_lenth;
tmp[0]= board_adr;
tmp[1]= READ_COIL;
tmp[2]= start_address/256;
tmp[3]= start_address & 0xff;
tmp[4]= lenth/256;
tmp[5]= lenth &0xff;
tmp_lenth=6;
construct_ascii_frm (com_buf,tmp,tmp_lenth);
return 17;
}
int rtu_read_coil_status ( unsigned char board_adr,unsigned char *com_buf,int start_address,int lenth) 

{
unsigned char tmp[256],tmp_lenth;
tmp[0]=board_adr;
tmp[1]=READ_COIL;
tmp[2]= start_address/256;
tmp[3]=start_address & 0xff;
tmp[4]= lenth/256;
tmp[5]= lenth &0xff;
tmp_lenth=6;
construct_rtu_frm ( com_buf,tmp,tmp_lenth);
return 8;
}
/*
2 读取开关量输入
发送：
*/
int ascii_read_input_status ( unsigned char board_adr,unsigned char *com_buf,int start_address,int lenth) 

{
unsigned char tmp[256],tmp_lenth;
tmp[0]=board_adr;
tmp[1]=READ_DI;
tmp[2]= start_address/256;
tmp[3]=start_address & 0xff;
tmp[4]= lenth/256;
tmp[5]= lenth &0xff;
tmp_lenth=6;
construct_ascii_frm ( com_buf,tmp,tmp_lenth);
return 17;
}
int rtu_read_input_status ( unsigned char board_adr,unsigned char *com_buf,int start_address,int lenth) 

{
unsigned char tmp[256],tmp_lenth;
tmp[0]=board_adr;
tmp[1]=READ_DI;
tmp[2]= start_address/256;
tmp[3]=start_address & 0xff;
tmp[4]= lenth/256;
tmp[5]= lenth &0xff;
tmp_lenth=6;
construct_rtu_frm ( com_buf,tmp,tmp_lenth);
return 8;
}
/*
3 读取保持寄存器
发送：
*/
int ascii_read_hldreg ( unsigned char board_adr,unsigned char *com_buf,int start_address,int lenth) 

{
unsigned char tmp[256],tmp_lenth;
tmp[0]=board_adr;
tmp[1]=READ_HLD_REG;
tmp[2]= start_address/256;
tmp[3]=start_address & 0xff;
tmp[4]= lenth/256;
tmp[5]= lenth &0xff;
tmp_lenth=6;
construct_ascii_frm ( com_buf,tmp,tmp_lenth);
return 17;
}

int  rtu_read_hldreg ( unsigned char board_adr,unsigned char *com_buf,int start_address,int lenth) 

{
unsigned char tmp[256],tmp_lenth;
tmp[0]=board_adr;