hello ,

          I have converted hexadecimal to decimal and i am able to print on GLCD, now i have to do suitable mathematical operation on decimal value and to print on GLCD, but i could not able to suceed. here is my sample  code

#define x=0.0762939453125;

void main()

{

                unsigned char    Pstring[ 16 ]     = "                ";
                unsigned char   y, z, voltage;

  {

  ___________

}

                  for ( i = 0; i < 16; Pstring[ i ] = '\0', i++ );   
                  
                   sprintf( Pstring, "%04d", ( uint16 ) ADC_Sample_Max );

                  GLCD_Text(40, 20, FONT_FIFTEEN_DOT,  Pstring);

// in the above line i am able to print decimal value , to do operations am doing below operations

                   voltage=Pstring*x;

                  voltage=voltage/20;

                  y=voltage+10;

                 z=y/0.19;

             GLCD_Text(40, 20, FONT_FIFTEEN_DOT,  z);  // here z value should print.

}

Here is sprintf() formating string examples that may help, attached.

Regards, Dana.

You have to repeat the same sprintf() operation on the second value

to use the GLCD Text function. Just as you did on the first value.

Regards,. Dana.

but i am getting error at

voltage=Pstring*x;

 and the following error is

.\main.c:140: error: expected expression before '=' token

Pstring is a pointer to an array of characters, you cannot multiply that with something. You will have to do a calculation and then convert the result to a string again.

Bob

Can you explain a bit further

Well, you probably are not used to C-Language, but it is not too difficult to learn...

x is defined as a float constant, y and z as an integer in the range 0 to 255, that does not look right, define y and z as float.

sprintf() converts given values into a humal readable form  (character string), there is no need to fill the string with '\0'.

You cannot do a multiplication operation with a string (what is "Hello World" * 3.14)

But you may use your ADC_Sample_Max again and multiply it with whatever you want.

Here is a link to my favorite C-manual: http://publications.gbdirect.co.uk/c_book/ 

Bob

Something like this

#define x = 0.0762939453125;

void main()

    unsigned char    Pstring[ 16 ]     = "                ";
    float            x, y, z, voltage;
    uint16            ADC_Sample_Max;       

    for ( i = 0; i < 16; Pstring[ i ] = '\0', i++ );               // Like Bob says, the sprintf() will null terminate the string for you
                                                                                      // when it is invoked, eg. you do not need this line of code
    sprintf( Pstring, "%04d", ( uint16 ) ADC_Sample_Max );
    GLCD_Text(40, 20, FONT_FIFTEEN_DOT,  Pstring);

    voltage = ( (float) ADC_Sample_Max * x ) / 20;
    y = voltage + 10;                                            // Not sure why you need y and z......
    z = y / 0.19;
    GLCD_Text(40, 20, FONT_FIFTEEN_DOT,  z);                      // here z value should print.

}

Last lines should read

sprintf( Pstring, "%04d", ( uint16 ) z );
    GLCD_Text(40, 20, FONT_FIFTEEN_DOT,  Pstring); // here z value should print.
 

Bob

Thanks Bob for picking up on that, when I looked at it

I kept thinking I had to dupe the conversion and GLCD

lines, completely forgot to do that.

Senior momentus.

i did it in other way , to convert to hex to dec i used shift operation and then multiplied by suitable constant

                            temp=ADC_Sample_Max;
                            no1=temp & 0x001;
                            no1=no1*1;
                            temp=ADC_Sample_Max;

                            temp=temp>>1;
                            no2=temp & 0x001;
                            no2=no2*2;
                            temp=ADC_Sample_Max;