A/D conversion for 89LPC925

[Vikky]

Hi all,

I want the ADC code for 89LPC925. I have developed it according to understanding. But i think i am missing some where. Here is my code

include "stdio.h"
#include "reg925.h"


unsigned char converted_data;

void main()
{	
	int i;	

	ADMODB |= 0x40;   //Configuring clock divider and selecting ADC mode

    	P0M1 |= 0x02;  // configuring ADC chanel1 Port0.1 as input.
	P0M2 &= ~0x02 ;
	P1M1 = 0x00;
	P1M2 = 0x00;  	
	
	ADMODB &= ~0x08; // Disabling DAC

	IP1 &= 0x7F; //Interrupt priorities
	IP1H &= 0x7F;

	EAD = 1 ;   //Enabling ADC Interrupt

	ADMODA |= 0x40;		  // ADC conversion mode autoscan and continous

	ADINS &= 0x10;    // Select ADC chanel 0.	 

	ADCON1 |= 0x45;	   // Start conversion immediatly, enable ADC interrupt

	while(1)
	{
	 if (ADCON1 & 0x08)		// Conversion Completed?
		{
		 converted_data = AD1DAT0; // save the result
		ADCON1 &= ~0x08;        // clear ADCI1 flag	 
			
	
		serial(converted_data); // send the data serially

		for (i=0;i<300;i++)
			{
			} 
		}
	}
}

The serial data sending part is running fine. I think that the data are not been converted into the digital format. Can naybody pass me the sample code of the ADC for 89LPC925??

Thanks

 

[Vikky]

Hi all,

To get the status of the programm i have slightly modified the my previous code and try to get the converted value from the ADC on the hyterterminal. The code is

#include "stdio.h"
#include "reg925.h"

void serial(unsigned char hyper_data);
unsigned char converted_data;

void main()
{	
	int i;	

	ADMODB |= 0x60;     //Configuring clock divider and selecting ADC mode
	ADMODA |= 0x20;	    //   ADC conversion mode autoscan and continous

   	P0M1 = 0x1E;
	P0M2 = 0x00;
	P1M1 = 0x00;
	P1M2 = 0x00;  	
	
	TMOD = 0X20;
	TH1 = 0Xf4;
	SCON = 0X50;
	TR1 = 1	;

	serial('A');
	serial('D');
	serial('C');
	serial(' ');
	
	serial('S');
	serial('T');
	serial('A');
	serial('R');
	serial('T');

	ADCON1 |= 0x45;  //  Start conversion immediatly, enable ADC interrupt	   

	while(1)
	{
		while((ADCON1 & 0x08) != 0x08)  // Conversion Completed?
			{
			}

	        converted_data = AD1DAT0; // save the result
			ADCON1 = 0x00;        // clear ADCI1 flag
			

			serial('A');
			for (i=0;i<300;i++)
				{
				}
	
			serial(converted_data);

			for (i=0;i<300;i++)
				{
				} 
			
	}
}
 
void serial(unsigned char hyper_data)
{	     
	SBUF = hyper_data;
	while(TI == 0);
	TI = 0;
}

Here on the Hyperterminal i can view only "ADC START". But after that nothing happens. I have even kept a display of character "A" after each ADC value, but that too did not come upto to screen.

Need help.