[SOLVED] Need a sample c- code for displaying register data on lcd (16x2) .

abv · Oct 9, 2012

I'm new to analog part of 16f877a .Also I didn't know how to print directly from register (ADRESL/H) because i always use pointer to display on my lcd.
I'm using MPLab with htc compiler.Please help me to get a sample C-code for displaying from register. :|

Jestin_cubetech · Oct 9, 2012

Code:

//configuration part
 TRISA=0x01; ADCON1=0xc0;        //port A.0 ADC input 

//adc read function
unsigned int read_adc()
{
unsigned int temp;
  ADCON0=0x81;    //read from ADC channel 1
  __delay_ms(1);    //setting time 
  ADGO=1;    while(ADGO);   // wait until ADC conversion complete 
  temp=(ADRESH<<8|ADRESL);  // combine 10 bit result 
return temp;
}

//display function

void lcd_number_display(unsigned int adc)
{
 unsigned char a[5]={0,0,0,0,0},cnt=0;   
if(adc==0) { cnt=1; }


    while(adc)
      {
		a[cnt++]=(adc%10);
		adc=(adc/10);
      }

     while(cnt--)
     {
       lcd_data((a[cnt]+'0'));    //your single character display  LCD function    [ +'0' means  add ascii value for display ]
     }

bigdogguru · Oct 10, 2012

Jestin_cubetech said:

Code:

//configuration part
 TRISA=0x01; ADCON1=0xc0;        //port A.0 ADC input 

//adc read function
unsigned int read_adc()
{
unsigned int temp;
  ADCON0=0x81;    //read from ADC channel 1
  __delay_ms(1);    //setting time 
  ADGO=1;    while(ADGO);   // wait until ADC conversion complete 
[COLOR="#FF0000"]  temp=(ADRESH<<8|ADRESL);  // combine 10 bit result [/COLOR]
return temp;
}

//display function

void lcd_number_display(unsigned int adc)
{
 unsigned char a[5]={0,0,0,0,0},cnt=0;   
if(adc==0) { cnt=1; }


    while(adc)
      {
		a[cnt++]=(adc%10);
		adc=(adc/10);
      }

     while(cnt--)
     {
       lcd_data((a[cnt]+'0'));    //your single character display  LCD function    [ +'0' means  add ascii value for display ]
     }

While your code example may yield the expected results when compiled using the MikroC compiler,
it typically will not yield the expected result when compiled with a compiler more compliant with the C standards.

The issue is due to the statement highlighted in red:

Code:

  temp=(ADRESH<<8|ADRESL);  // combine 10 bit result

The following part of the statement:

Code:

ADRESH<<8

Shifts the entire contents of the byte out, effectively clearing the byte.

A compiler compliant to the C standards would require you first cast ADRESH to a higher rank type, like an unsigned int, before shifting the contents eight place to the left.

Another, less used, but very powerful option would be to employ a type structure comprised of a union of a type unsigned int and two unsigned bytes.

Code:

typedef union{
unsigned int int_value;
struct{
    unsigned char hibyte;
    unsigned char lobyte;
}parts;
}int_convert;

Example Use:

Code:

     int_convert  adcvalue;

    adcvalue.parts.hibyte = ADRESH;
    adcvalue.parts.lobyte = ADRESL;

    unsigned int combinedvalues = adcvalue.int_value;

BigDog

Jestin_cubetech · Oct 10, 2012

Code:

this code working with hitech C

temp=(ADRESH<<8|ADRESL);  // combine 10 bit result 

/////////////////////////////////////////////
alternative code 

temp=ADRESH;
temp<<=8;
temp|=ADRESL;

abv · Oct 10, 2012

thanks for the code..

[SOLVED] Need a sample c- code for displaying register data on lcd (16x2) .

abv

Newbie level 5

Jestin_cubetech

Advanced Member level 1

abv

bigdogguru

Administrator

abv

Jestin_cubetech

Advanced Member level 1

abv

abv

Newbie level 5

Similar threads

[SOLVED] Need a sample c- code for displaying register data on lcd (16x2) .

Newbie level 5

Advanced Member level 1

Administrator

Advanced Member level 1

Newbie level 5

Similar threads

Privacy & Transparency

Privacy & Transparency