ad_test.c

将模拟温度传感器与数字转换接口电路集成在一起

/*********************************************************************************************
* File：	ad_test.c
* Author:	embest
* Desc：	ad_test source code
* History:	
*********************************************************************************************/
#include "44b.h"
#include "44blib.h"

/*------------------------------------------------------------------------------------------*/
/*	 								function declare					 				    */
/*------------------------------------------------------------------------------------------*/
int adc_value(void);

/*********************************************************************************************
* name:		Main
* func:		c code entry
* para:		none
* ret:		none
* modify:
* comment:		
*********************************************************************************************
void Main(void)
{	
	int temp;
	sys_init();                                                 // Initial 44B0X's Interrupt,Port and UART 
	init_adc();
	//user interface 
	uart_printf("\n\r Embest Arm EduKit II Evaluation Board");
	uart_printf("\n S3C44B0x ADC Conversion Test Example\n");
	for(;;){
	temp=adc_test(); 
	}                                                // Test start
	
}

/*********************************************************************************************
* name:		adc_test
* func:		test adc
* para:		none
* ret:		none
* modify:
* comment:		
*********************************************************************************************/
int adc_value(void)
{
	int i,value=0;
   	init_adc();
	    
	//AIN2 AD conversion
    for(i=0;;i++)
    {
		rADCCON = 0x1 | (0x2<<2);	                            // AIN2
		while( !(rADCCON&0x40) );	                            // wait  conversion finish
				
		if((value-78)<0) {value=0;}
		else {value=value-78;}
		value+=rADCDAT;
		if(i==20){
		i=0;
		value=(value/20);		
		uart_printf( "Ain2 = %d\n", value );
		return(value);
		}
    }
}

void init_adc(void){
	// Initialize adc
	rCLKCON = 0x7ff8;
	rADCCON = 0x1 | (0<<2);                                     // Enable ADC
	delay(100);                                                 // delay for 10ms for ADC reference voltage stabilization.
	rADCPSR = 100; 
}