master-example.c

libmodbus version 0.04

#include <modbus.h>

/* compiling : gcc master-example.c -o master-example -lmodbus */

int main()
{
   int device;
   Mbm_trame trame;
   int result;
   int data_in[256];
   int data_out[256];
   char data[256];

   /* open device */
   device=Mb_open_device("/dev/ttyS0",9600,0,8,1);

   /* print debugging informations */
   Mb_verbose=0;
   
   /* setup master packet */
   trame.device=device;
   trame.function=16;			/* send data */
   trame.slave=1;					/* slave number*/ 
//   trame.address=0xa24 -1;
   trame.address=2596;
   trame.length=4;
   trame.timeout=10000;
   
   /* setup data to send */
   data_in[0]=0;
   data_in[1]=0;
/*   data_in[2]=3;
   data_in[3]=4;
   data_in[4]=5;
   data_in[5]=5;
   data_in[6]=5;
   data_in[7]=5;
   data_in[8]=5;
*/

   result=Mb_master(trame,data_in,data_out,NULL,NULL);
   /* return 0 if ok */
   if (result<0)
   {
      if (result==-1) printf("error : unknow function\n");
      if (result==-2) printf("crc error\n");
      if (result==-3) printf("timeout error\n");
      if (result==-4) printf("error : bad slave answer\n");
   }
   else
      printf("ok\n");

   trame.function=3;			/* send data */
   trame.slave=1;					/* slave number*/ 
//   trame.address=0xa28;
   trame.address=1043;
   trame.length=11;
   trame.timeout=10000;


   result=Mb_master(trame,data_in,data_out,NULL,NULL);
   /* return 0 if ok */
   if (result<0)
   {
      if (result==-1) printf("error : unknow function\n");
      if (result==-2) printf("crc error\n");
      if (result==-3) printf("timeout error\n");
      if (result==-4) printf("error : bad slave answer\n");
   }
   else
      printf("ok\n");

   data[0] = (char) ((data_out[0] & 0xff00) >> 8);
   data[1] = (char) (data_out[0] & 0x00ff);
   data[2] = (char) ((data_out[1] & 0xff00) >> 8);
   data[3] = (char) (data_out[1] & 0x00ff);
   data[4] = (char) ((data_out[2] & 0xff00) >> 8);
   data[5] = (char) (data_out[2] & 0x00ff);
   data[6] = (char) ((data_out[3] & 0xff00) >> 8);
   data[7] = (char) (data_out[3] & 0x00ff);
   data[8] = (char) ((data_out[4] & 0xff00) >> 8);
   data[9] = (char) (data_out[4] & 0x00ff);
   data[10] = (char) ((data_out[5] & 0xff00) >> 8);
   data[11] = (char) (data_out[5] & 0x00ff);
   data[12] = (char) ((data_out[6] & 0xff00) >> 8);
   data[13] = (char) (data_out[6] & 0x00ff);
   data[14] = (char) ((data_out[7] & 0xff00) >> 8);
   data[15] = (char) (data_out[7] & 0x00ff);
   data[16] = (char) ((data_out[8] & 0xff00) >> 8);
   data[17] = (char) (data_out[8] & 0x00ff);
   data[18] = (char) ((data_out[9] & 0xff00) >> 8);
   data[19] = (char) (data_out[9] & 0x00ff);
   data[20] = (char) ((data_out[10] & 0xff00) >> 8);
   data[21] = (char) (data_out[10] & 0x00ff);
   data[22] = (char) ((data_out[11] & 0xff00) >> 8);
   data[23] = '\0';

   printf("string = .%s.\n", data);

   Mb_verbose=1;
   trame.function=3;                    /* send data */
   trame.slave=1;                                       /* slave number*/
   trame.address=2584;
   trame.length=1;
   trame.timeout=10000;
                                                                                                            
                                                                                                            
   result=Mb_master(trame,data_in,data_out,NULL,NULL);
   /* return 0 if ok */
   if (result<0)
   {
      if (result==-1) printf("error : unknow function\n");
      if (result==-2) printf("crc error\n");
      if (result==-3) printf("timeout error\n");
      if (result==-4) printf("error : bad slave answer\n");
   }
   else
      printf("ok\n");
   Mb_verbose=0;



   trame.function=3;			/* send data */
   trame.slave=1;					/* slave number*/ 
   trame.address=2600;
   trame.length=21;
   trame.timeout=10000;


   result=Mb_master(trame,data_in,data_out,NULL,NULL);
   /* return 0 if ok */
   if (result<0)
   {
      if (result==-1) printf("error : unknow function\n");
      if (result==-2) printf("crc error\n");
      if (result==-3) printf("timeout error\n");
      if (result==-4) printf("error : bad slave answer\n");
   }
   else
      printf("ok\n");


   data[0] = (char) ((data_out[2] & 0xff00) >> 8);
   data[1] = (char) (data_out[2] & 0x00ff);
   data[2] = (char) ((data_out[3] & 0xff00) >> 8);
   data[3] = (char) (data_out[3] & 0x00ff);
   data[4] = (char) ((data_out[4] & 0xff00) >> 8);
   data[5] = (char) (data_out[4] & 0x00ff);
   data[6] = (char) ((data_out[5] & 0xff00) >> 8);
   data[7] = (char) (data_out[5] & 0x00ff);
   data[8] = (char) ((data_out[6] & 0xff00) >> 8);
   data[9] = (char) (data_out[6] & 0x00ff);
   data[10] = (char) ((data_out[7] & 0xff00) >> 8);
   data[11] = (char) (data_out[7] & 0x00ff);
   data[12] = (char) ((data_out[8] & 0xff00) >> 8);
   data[13] = (char) (data_out[8] & 0x00ff);
   data[14] = (char) ((data_out[9] & 0xff00) >> 8);
   data[15] = (char) (data_out[9] & 0x00ff);
   data[16] = (char) ((data_out[10] & 0xff00) >> 8);
   data[17] = (char) (data_out[10] & 0x00ff);
   data[18] = (char) ((data_out[11] & 0xff00) >> 8);
   data[19] = (char) (data_out[11] & 0x00ff);
   data[20] = '\0';

   printf("string = .%s.\n", data);


   Mb_close_device(device);

   return 0;
}