[PIC] 10 bit result of ADC is require to convert in decimal to display in LCD

[ecaits]

I am using 16F877 pic controller.
I have prepared code for ADC.
Analog input is converted in to ADC result. Now I want to convert that hex number to decimal to display in lcd.

Plz support how can i convert hex to decimal for ADC 10 bit output???

 

[wp100]

Hi,

Your ADC result needs to be converted to ASCII format to be displayed on a lcd.

However, how you do that is depends on the compiler you are using, which is ...?

 

[embpic]

use following code to write on lcd or u can send it to UART

void show_decimal(unsigned int numb)
{
	unsigned int temp;	  
	temp = numb/10000000;			  //1
	data_write(temp + '0');	

	temp = (numb/1000000)%10;		//2
	data_write(temp + '0');	

	temp = ((numb/100000)%100)%10;	   //3
	data_write(temp + '0');	
	
	temp = (((numb/10000)%1000)%100)%10;
	data_write(temp + '0');	

	temp = ((((numb/1000)%10000)%1000)%100)%10;
	data_write(temp + '0');	

	temp = (((((numb/100)%100000)%10000)%1000)%100)%10;
	data_write(temp + '0');	

	temp = ((((((numb/10)%1000000)%100000)%10000)%1000)%100)%10;
	data_write(temp + '0');

	temp = (((((((numb/1)%10000000)%1000000)%100000)%10000)%1000)%100)%10;
	data_write(temp + '0');
}

first it gives MSB then towards LSB.

 

[paulfjujo]

hello,

temp = numb/10000000;

temp = (numb/1000000)%10;

temp = ((numb/100000)%100)%10;

i suspect a probleme, even i didn't try your code... for the first 3 items..
because you will allways get 0 as result with using unsigned int for variable Temp.
(Divider is over range > 65535 !)


i propose this code , C18 MPLAB
use a long int as intermediate calculus , and a flag to push "0" or "space" to get a constant width of char
and another flag to print out on USART or LCD

#define OUT_RS232 Drapeaux.Lcd=0;
#define OUT_LCD Drapeaux.Lcd=1;


unsigned char Entree[17]="1234567890123456";
unsigned char *valtxt;
 struct chbits {   // 8 flags
                 unsigned FrameErr:1;
                 unsigned Over:1;
                 unsigned Elligible:1;
                 unsigned Togle:1;
                 unsigned Blc:1;
                 unsigned standby:1;
                 unsigned Fill:1;
                 unsigned Lcd:1;
               }Drapeaux ;


 union
{  unsigned char Fanion;
   struct chbits Drapeaux ;
} Flags;








void Write_Word_(unsigned int M,char Sign)
{
unsigned int i,k,l;
unsigned long M1;
 valtxt=&Entree[0];
 if (Sign>1) return;
 if (Sign==0)
  {       M1=M;
        ultoa(M1,&Entree[0]);
  }
  else itoa(M,&Entree[0]);
 if (Flags.Drapeaux.Fill)
 {
  k=strlen(Entree);
  for (i=0;i<k;i++) Entree[4+Sign-i]=Entree[k-i-1];
  for (i=0;i<(5+Sign-k);i++)
  {if (Flags.Drapeaux.Blc) Entree[i]='0'; else Entree[i]=' ';}
 }
 Entree[5+Sign]=0;
 #ifdef LCD2x16
 if (Flags.Drapeaux.Lcd==1) LCD_PutRamString(valtxt); else k=PutStr_RS(valtxt);
 #else
 k=PutStr_RS(valtxt);
 #endif
}

 

[embpic]

may be for 4 byte

 

[ecaits]

In this case, First i will get ADC output in 10bit and will stored in register ADRESH and ADRESL and this output is in hex form.
Now I need to convert this 10 bit hex code in one decimal number.
After getting one decimal number I have to use that division and modulo operation.

My question is, i will get direct one decimal number or i need to convert 10 bit hex code into one decimal number???

 

[paulfjujo]

hello,

My question is, i will get direct one decimal number or i need to convert 10 bit hex code into one decimal number??

Inside every MCU , value are always in binary mode .. 0 or 1
so when you get the result of ADC
You get a binary value...from the 2 register of 8 bits ...
and combine them into a register of 16 bits
but only 10 bits are significatif, so
after a Right alignment , you can use this 16 bits register wich can contain a binary value from
0000000000000000 to 0000001111111111

after you can use or represente it for displaing
as an hexadecimal value with 4 digits
0000 to 03FF
or decimal value with 5 digits
0000 to 1023

on evoluate PIC18F in C18 langage it is easy to use differnet mode for displayng the value
example

M=read(ADC);
//we suppose result of reading ADC is in the integer value M = 512
 k=fprintf(_H_USART," M=%04u      M=%4X ", M,M);

will print on terminal RS232 (via UART)
M=0512 M=0200

 

[ecaits]

I am using hi-tech compiler....

 

[jayanth.devarayanadurga]

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Code C - [expand]
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unsigned char digits[5];
unsigned int adcval;
 
 
void main(){
 
 
    while(1){
 
        digits[0] = adcval / 1000 + 48;
        digits[1] = (adcval / 100) % 10 + 48;
        digits[2] = (adcval / 10) % 10 + 48;
        digits[3] = adcval % 10 + 48;
        digits[4] = '\0';
 
        lcd_string(digits);
 
    }
}

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[ecaits]

Here, do I need to convert 10 bit ADC result to Decimal value??? Or can i directly assign 10 bit ADC result to variable "adcval" and use above division-modulo operation???

 

[embpic]

by doing so you are doing same thing to convert it to decimal and then need to convert to ASCII

 

[jayanth.devarayanadurga]

You only need to assign 10 bit ADC result to adcval using

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Code C - [expand]
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adcval = (ADRESH << 8) | ADRESL;

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