how to convert array of uchar to string

[therock112]

hello

I am new to C and not sure how to go about getting the following accomplished:

I have the following c code, under centos ver 3.4, using gnu gcc to compile:

uchar sn[8];

// readings

sn[0] = 0x10;
sn[1] = 0x2E;
sn[2] = 0x22;
sn[3] = 0x47;
sn[4] = 0x00;
sn[5] = 0x08;
sn[6] = 0x00;
sn[7] = 0x35;

I want to convert the above array into an Ascii string, is there any simple way of achieving this in C?

ultimately i want to do the following:

query = "Insert into test (reading) values(sn)";
// i want to get it formated as "Insert into test (reading) values ('3500080047222 E10')"
// I understand that c will not insert the value of the array 'sn', unlike php or other glue languages...i am hoping there is some way to achieve this..

do_this_query(q uery);

any help would be appreciated.

[therock112]

any ideas, anyone???

[sivadhas2006]

Hi,

Can you post your full code?

Can I know from where you are getting these values?

sn[0] = 0x10;
sn[1] = 0x2E;
sn[2] = 0x22;
sn[3] = 0x47;
sn[4] = 0x00;
sn[5] = 0x08;
sn[6] = 0x00;
sn[7] = 0x35;

So we can think to solve the problem differently.

Regards,
M.Sivadhas.

[therock112]

Can you post your full code?

Sure.

My following code is a direct copy from Dallas/Maxim's site, I have tried to incorporate the Mysql c api in it as well so I could directly send the measured temperature information to a sql table.

for the fullsource code from dallas, please visit the following site to get their sdk
:

http://files.dalsemi.com/auto_id/public/ulinuxgnu300.zip

Following is my hacked c code, please bear in mind I am not a programmer, so I am pretty new to this stuff. For the original code from Dallas, you may want to see the temp.c from the above sdk.

#include <stdlib.h>
#include <stdio.h>
#include <mysql.h>
#include <string.h>
#include "ownet.h"
#include "temp10.h"
#include "findtype.h"

// defines
#define MAXDEVICES         20

// global serial numbers
uchar FamilySN[MAXDEVICES][8];

uchar *fsn; // not part of original dallas code
uchar *fsnid; // not part of original dallas code

// MySQL db info
// #define user     'log'
// #define pass     '4321'
// #define hostname 'localhost'
// #define dbname   'tlogs'

// variables
int family_code;

//----------------------------------------------------------------------
//  Main Test for DS1920/DS1820 temperature measurement
//
int main(int argc, char **argv)
{

// MySQL stuff

   MYSQL mysql; // not part of original dallas code
   MYSQL_RES *res; // not part of original dallas code
   MYSQL_ROW row; // not part of original dallas code

   char query[200]; // not part of original dallas code
   mysql_init(&mysql); // not part of original dallas code

// OneWire Stuff

   float current_temp;
   int i = 0;
   int NumDevices=0;
   int portnum = 0;

   //----------------------------------------
   // Introduction header
   printf("\n/---------------------------------------------\n");

   printf("  Press any CTRL-C to stop this program.\n\n");
   printf("  Output [Serial Number(s) ........ Temp1(F)] \n\n");

   // check for required port name
   if (argc != 1)
   {
      printf("1-Wire Net name required on command line!\n"
             " (example: \"COM1\" (Win32 DS2480),\"/dev/cua0\" "
             "(Linux DS2480),\"1\" (Win32 TMEX)\n");
      exit(1);
   }


   // attempt to acquire the 1-Wire Net
   if((portnum = owAcquireEx("/dev/ttyS0")) < 0)
   {
      OWERROR_DUMP(stdout);
      exit(1);
   }

   // success
   printf("Port opened: %s\n",argv[1]);

   // open connection to mysql server
   mysql_real_connect(&mysql,"localhost","log","4321","tlogs",0,NULL,0);
   printf("\n Connection opened to MySQL server\n");


   // Find the device(s)
   NumDevices = FindDevices(portnum, &FamilySN[0], 0x10, MAXDEVICES);

printf("\n Got here 1 \n"); // simple debug 

   // Write the discovered device info to MySQL server
   if (NumDevices>0)
   {

printf("\n Got here 2 \n"); // simple debug 

      for (i = 0; i < NumDevices; i++)
      {

printf("\n Got here 3 \n"); // simple debug 


	fsn = FamilySN[i]; // not part of original dallas code
	fsnid = &FamilySN[i][0];  // not part of original dallas code
	
	// query = "INSERT into rawtemp (id, deviceid, devicetype, temp, logtime, logdate) VALUES(,";

printf("Serial Number %i", strlen(FamilySN[i])); // not part of original dallas code

	//  + fsn + "," + fsnid + "," + "22.10,,)"; 

	// sprintf(query,query);
	//sprintf(query,"INSERT into rawtemp (id, deviceid, devicetype, temp, logtime, logdate) VALUES(,fsn,fsnid,21,curtime(),curdate())");

printf("\n Got here 4 \n");

// printf("Query = %s\n", query);

	mysql_real_query(&mysql,query,(unsigned int)strlen(query));
//	query = "INSERT into rawtemp (id, deviceid, devicetype, temp, logtime, logdate) VALUES(,fsn,'10',,,);
//	mysql_query(&mysql, query);

printf("\n Got here 5 \n");

//	res = mysql_use_result(&mysql);
//	printf("\n Wrote record %i to MySQL server\n",i);
      }

     // close and reslease connection mysql server
     mysql_free_result(res);
     printf("\n Connection close to MySQL server\n");

   }

   if (NumDevices>0)
   {
      printf("\n");
      printf("Device(s) Found: \n");
      for (i = 0; i < NumDevices; i++)
      {
         PrintSerialNum(FamilySN[i]);
         printf("\n");
      }
      printf("\n\n");


      // (stops on CTRL-C)
      do
      {
         // read the temperature and print serial number and temperature
         for (i = 0; i < NumDevices; i++)
         {

            if (ReadTemperature(portnum, FamilySN[i],&current_temp))
            {
               PrintSerialNum(FamilySN[i]);
               printf("%5.1f \n", current_temp);
            }
            else
               printf("     Error reading temperature, verify device present:%d\n",
                       (int)owVerify(portnum, FALSE));
         }
         printf("\n");
      }
      while (!key_abort());
   }
   else
      printf("\n\n\nERROR, device DS1920/DS1820 not found!\n");

   // release the 1-Wire Net
   owRelease(portnum);
   printf("Closing port %s.\n", argv[1]);
   exit(0);

   return 0;
}

I hope this is not too confusing to understand. I am familiar with php, but php has extensive string handling capabilities. I am trying to figure out how to achieve some of the simplest string manipulation in C, so far it seems like its much more complex than in php.

Also the following :

sn[0] = 0x10;
sn[1] = 0x2E;
sn[2] = 0x22;
sn[3] = 0x47;
sn[4] = 0x00;
sn[5] = 0x08;
sn[6] = 0x00;
sn[7] = 0x35;

is the address of a temperature sensor.

any ideas would be helpful to get this code to read temperature from the one wire bus and write them to a mysql table.

thanks.

[horace1]

a simple way to convert your array into a string would be to use sprintf(), e.g. using the %x conversion specification to get hexadecimal output

#include <stdio.h>

int main()
{
    int i, sn[8];
    sn[0] = 0x10;
    sn[1] = 0x2E;
    sn[2] = 0x22;
    sn[3] = 0x47;
    sn[4] = 0x00;
    sn[5] = 0x08;
    sn[6] = 0x00;
    sn[7] = 0x35;
    for(i=0; i<8;i++) printf("%x ", sn[i]);
    char text[20];
    // convert hex values in sn[] into a string in text[]
    sprintf(text,"%x%x%x%x%x%x%x%x",sn[7],sn[6],sn[5],sn[4],sn[3],sn[2],sn[1],sn[0]);
    printf("\ntext = '%s'\n", text);
getchar();
}

a run of this gave
10 2e 22 47 0 8 0 35
text = '3508047222e10'

[therock112]

a simple way to convert your array into a string would be to use sprintf(), e.g. using the %x conversion specification to get hexadecimal output

    char text[20];
    // convert hex values in sn[] into a string in text[]
    sprintf(text,"%x%x%x%x%x%x%x%x",sn[7],sn[6],sn[5],sn[4],sn[3],sn[2],sn[1],sn[0]);
    printf("\ntext = '%s'\n", text);
getchar();
}

horace1, thats exactly what I was looking for.....thanks a million

following is what I came up with, and it works!!!!


sprintf(devicea ddress,"%02x%02 x%02x%02x%02x%0 2x%02x%02x",Fam ilySN[i][7],FamilySN[i][6],FamilySN[i][5],FamilySN[i][4],FamilySN[i][3],FamilySN[i][2],FamilySN[i][1],FamilySN[i][0]);

sprintf(query, "INSERT into tlogs (id, deviceid, devicetype, temp, logtime, logdate) VALUES(0,'%s',' %x','%5.1f',cur time(), curdate())", deviceaddress,F amilySN[i][0],current_temp);

hopefully this helps someone out there.......

thanks again.

therock

[therock112]

horace1, thats exactly what I was looking for.....thanks a million

following is what I came up with, and it works!!!!


sprintf(devicea ddress,"%02x%02 x%02x%02x%02x%0 2x%02x%02x",Fam ilySN[i][7],FamilySN[i][6],FamilySN[i][5],FamilySN[i][4],FamilySN[i][3],FamilySN[i][2],FamilySN[i][1],FamilySN[i][0]);

sprintf(query, "INSERT into tlogs (id, deviceid, devicetype, temp, logtime, logdate) VALUES(0,'%s',' %x','%5.1f',cur time(), curdate())", deviceaddress,F amilySN[i][0],current_temp);

hopefully this helps someone out there.......

thanks again.

therock

Continuing the fun,

I now want to do the reverse of course, read from mysql database, and copy the deviceid into a variable, resulting in the same format.

when I receive the mysql result, the result is in string format, how do i go about converting those exact address such as 3500080047222E1 0 and correctly placing them in an array?

[therock112]

Continuing the fun,

I now want to do the reverse of course, read from mysql database, and copy the deviceid into a variable, resulting in the same format.

when I receive the mysql result, the result is in string format, how do i go about converting those exact address such as 3500080047222E1 0 and correctly placing them in an array?

I have tried the following without much luck:

mysql includes;
declare and init other varibles etc;

int NumDevices =0;

other mysql related initialization, not shown to keep things simple;

sprintf(query, "SELECT distinct ucase(deviceid) from tlogs where devicetype='10'");

mysql_real_query(&mysql,query,(unsigned int)strlen(query));

res = mysql_use_result(&mysql);
while((row = mysql_fetch_row(res)))
{
printf("\nTemperature Sensor ID's =  %s\n", row[0]); // this prints correctly.

sscanf(row[0],"%02x%02x%02x%02x%02x%02x%02x%02x", arrayofuchars[NumDevices][7],arrayofuchars[NumDevices][6],arrayofuchars[NumDevices][5],arrayofuchars[NumDevices][4],arrayofuchars[NumDevices][3],arrayofuchars[NumDevices][2],arrayofuchars[NumDevices][1],arrayofuchars[NumDevices][0]);

printf("Device id = %02x%02x%02x%02x%02x%02x%02x%02x\n", arrayofuchars[NumDevices][7],arrayofuchars[NumDevices][6],arrayofuchars[NumDevices][5],arrayofuchars[NumDevices][4],arrayofuchars[NumDevices][3],arrayofuchars[NumDevices][2],arrayofuchars[NumDevices][1],arrayofuchars[NumDevices][0]); // prints unexpected stuff

NumDevices++;
}

after the sscanf, i was hoping to get this into the array:

arrayofuchars[0][7] = 0x35;
arrayofuchars[0][6] = 0x00;
arrayofuchars[0][5] = 0x08;
arrayofuchars[0][4] = 0x00;
arrayofuchars[0][3] = 0x47;
arrayofuchars[0][2] = 0x22;
arrayofuchars[0][1] = 0x2E;
arrayofuchars[0][0] = 0x10;

but I am sure, my lack of knowledge of c and its functions, operators etc etc is the cause of my hair pulling and screaming and frustration!!!

any help would be appreciated.

thanks.

[horace1]

I have tried the following without much luck:

sscanf(row[0],"%02x%02x%02x%02x%02x%02x%02x%02x", arrayofuchars[NumDevices][7],arrayofuchars[NumDevices][6],arrayofuchars[NumDevices][5],arrayofuchars[NumDevices][4],arrayofuchars[NumDevices][3],arrayofuchars[NumDevices][2],arrayofuchars[NumDevices][1],arrayofuchars[NumDevices][0]);

}

but I am sure, my lack of knowledge of c and its functions, operators etc etc is the cause of my hair pulling and screaming and frustration!!!

any help would be appreciated.

thanks.

you need to pass the address of the elements of array arrayofuchars[][] to scanf using the addressof operator &, e.g.

sscanf(row[0]"%02x%02x%02x%02x%02x%02x%02x%02x", &arrayofuchars[NumDevices][7],&arrayofuchars[NumDevices][6],&arrayofuchars[NumDevices][5],&arrayofuchars[NumDevices][4],&arrayofuchars[NumDevices][3],&arrayofuchars[NumDevices][2],&arrayofuchars[NumDevices][1],&arrayofuchars[NumDevices][0]);

[therock112]

you need to pass the address of the elements of array arrayofuchars[][] to scanf using the addressof operator &, e.g.

sscanf(row[0]"%02x%02x%02x%02x%02x%02x%02x%02x", &arrayofuchars[NumDevices][7],&arrayofuchars[NumDevices][6],&arrayofuchars[NumDevices][5],&arrayofuchars[NumDevices][4],&arrayofuchars[NumDevices][3],&arrayofuchars[NumDevices][2],&arrayofuchars[NumDevices][1],&arrayofuchars[NumDevices][0]);

I get some strange result, most of characters are 0's except the last 2 digits which gets converted correctly.....n ot sure why

when row[0] is 36000800402AE11 0
arrayofuchars[NumDevices] has 000000000000001 0

and it does this for all items, not sure why only the 10 gets converted correctly.

my exact syntax is as follows:

sscanf(row[0],"%02X%02X%02X%02X%02X%02X%02X%02X",&arrayofuchars[NumDevices][7],&arrayofuchars[NumDevices][6],&arrayofuchars[NumDevices][5],&arrayofuchars[NumDevices][4],&arrayofuchars[NumDevices][3],&arrayofuchars[NumDevices][2],&arrayofuchars[NumDevices][1],&arrayofuchars[NumDevices][0]);

I have tried upper case x and lowercase x, no difference.

arrayofuchars is defined as follows, arrayofuchars is global by the way:

uchar arrayofuchars[20][8];

[horace1]

I think the problem is that you have defined the array arrayofuchars[20][8] as being uchar (which I assume is unsigned char). The %02x conversion specification to sscanf assumes the corresponding parameter is int* (pointer to int). Try defining arrayofuchars[20][8] as

int arrayofuchars[20][8];

and see if it works. You can then copy the values into a uchar array later.

[therock112]

I think the problem is that you have defined the array arrayofuchars[20][8] as being uchar (which I assume is unsigned char). The %02x conversion specification to sscanf assumes the corresponding parameter is int* (pointer to int). Try defining arrayofuchars[20][8] as

int arrayofuchars[20][8];

and see if it works. You can then copy the values into a uchar array later.

Yes it works!!!

now, how do i go about copying int type array items into unsigned char type array?

is the following legit syntax?

arrayofuchars[deviceid][index] = arrayofints[deviceid][index];

or

arrayofuchars[deviceid][index] = (unsigned char) arrayofints[deviceid][index];