Good evening forum-
I am looking for guidance in completing an embedded c code for a PIC 16F684 that I have been working on. I am new to c for about a week coming over from pic assembly. Please see my code below for reference. This is just code for converting decimal to hexadecimal. My code performs what I need for a 8 bit integer dec to hex in MPLAB, X but I have the result stored in 2 eight bit variables and want it to be stored as one 8 bit integer in hex.
Could someone please guide me accomplishing this?

Shauna
******************************************************************

#include <xc.h>
#include <pic.h>


int mod, num = 148;
int k = 0, t = 0;


void main()

{  
  
  while(num>16)
  {
  mod = num%16;
  num = num/16;
  
  
  
  
  } //elihw
  
      if (num>9)
     {
       switch(num)
       {
         case 10:
         k='A';
         break;
         case 11:
         k='B';
         break;
         case 12:
         k='C';
         break; 
         case 13:
         k='D';
         break;
         case 14:
         k='E';
         break;
         case 15:
         k='F';
         break;
         default:
         NOP();
    }//hctiws
  }//fi
  
  if (mod>9)
   {
    switch(mod)
    {
      case 10:
      t='A';
      break;
      case 11:
      t='B';
      break;
      case 12:
      t='C';
      break; 
      case 13:
      t='D';
      break;
      case 14:
      t='E';
      break;
      case 15:
      t='F';
      break;
     default:
     NOP();
  
  
  }//hctiws
  }//fi  
  
  
  while(1==1);
}

Moderator edit: added code tags

 

I have the result stored in 2 eight bit variables and want it to be stored as one 8 bit integer in hex.

You can't do that. Suppose your number is 0xAA. Both k and t will be the character 'A'. That is 0x41 (65 decimal) and uses up 7 of the eight bits.

Incidentally this is not a good way of converting to hex. Ask Mr Google and he will show you better ways of doing it.

 

You can't do that. Suppose your number is 0xAA. Both k and t will be the character 'A'. That is 0x41 (65 decimal) and uses up 7 of the eight bits.

Incidentally this is not a good way of converting to hex. Ask Mr Google and he will show you better ways of doing it.

You can't do that. Suppose your number is 0xAA. Both k and t will be the character 'A'. That is 0x41 (65 decimal) and uses up 7 of the eight bits.

Incidentally this is not a good way of converting to hex. Ask Mr Google and he will show you better ways of doing it.

#include <xc.h>
#include <pic.h>


int mod, num = 148;
int k = 0, t = 0;


void main()

{

  while(num>16)
  {
  mod = num%16;
  num = num/16;




  } //elihw

      if (num>9)
     {
       switch(num)
       {
         case 10:
         k='A';
         break;
         case 11:
         k='B';
         break;
         case 12:
         k='C';
         break;
         case 13:
         k='D';
         break;
         case 14:
         k='E';
         break;
         case 15:
         k='F';
         break;
         default:
         NOP();
    }//hctiws
  }//fi

  if (mod>9)
   {
    switch(mod)
    {
      case 10:
      t='A';
      break;
      case 11:
      t='B';
      break;
      case 12:
      t='C';
      break;
      case 13:
      t='D';
      break;
      case 14:
      t='E';
      break;
      case 15:
      t='F';
      break;
     default:
     NOP();


  }//hctiws
  }//fi


  while(1==1);
}

[/QUOTE]

You can't do that. Suppose your number is 0xAA. Both k and t will be the character 'A'. That is 0x41 (65 decimal) and uses up 7 of the eight bits.

Incidentally this is not a good way of converting to hex. Ask Mr Google and he will show you better ways of doing it.

Mr. Hall,
Thank you for your reply. I did not want to simply cut and paste code I found on google but rather wanted to try and learn it by figuring it out, but I do see your direction there. I guess I will say this then, is it possible to do the following:
1) 0x09 and 0x0c are 2, 8 bit integers(9 and 12)
2) Swap bits, 0x09 becomes 0x90
3) Combine 0x90 and 0x0c to get 0x9C
4) 0x9c = 156 in decimal

This may not be possible but I thought I would post it to the forum to find out.

Shauna-

Moderator edit: added code tags

 

If k = 0x09 and t = 0x0C then you can do this:
k <<= 4; // k now is 0x90
k += t; // k now is 0x9C

 

Yup, that works.
If you are familiar with PIC assembly then you will know the 'swapf' command which does in 1 instruction what '>>4' does in four. You might hope that the compiler would be smart enough to perform the simplification. I don't know whether it does. You can use assembler in 'C' programs too (asm(); or the #asm construct).

 

Thank you all for your prompt, and respectful help in answering my question. I learned from this and that's what I was hoping for.

Shauna

 

• include <xc.h>

• #include <pic.h>

You want to read the compiler user guide first.