adc_test.c

在ARM（S3C2410）下实现AD转换器的运算和显示。

/*********************************************************************************************
* File：	adc_test.c
* Author:	embest
* Desc：	S3C2410 ADC Test 
* History:	
*		wang Fub 16th 2006
*********************************************************************************************/
/*------------------------------------------------------------------------------------------*/
/*                                     include files	                                    */
/*------------------------------------------------------------------------------------------*/
#include "2410lib.h"

/*------------------------------------------------------------------------------------------*/
/*                                     constants define                                     */
/*------------------------------------------------------------------------------------------*/
#define REQCNT 100							
#define ADC_FREQ 2500000
#define LOOP 10000

/*------------------------------------------------------------------------------------------*/
/*                                    variables declare                                     */
/*------------------------------------------------------------------------------------------*/
volatile UINT8T unPreScaler;
volatile char nEndTest;
/*********************************************************************************************
* name:		adc_test
* func:		ADC convert test
* para:		none
* ret:		none
* modify:
* comment:		
*********************************************************************************************/
void adc_test(void)
{
    int j;
	UINT16T usConData;
    float usEndData;
	    
    uart_printf("\n Adc Conversion Test Example \n");	
    uart_printf(" ADC_IN Test,channel 2\n");
	uart_printf(" ADC conv. freq. = %dHz\n",ADC_FREQ);
	unPreScaler = PCLK/ADC_FREQ -1;	
    rADCCON=(1<<14)|(unPreScaler<<6)|(2<<3)|(0<<2)|(1<<1);//enable prescaler,ain2,normal,start by read
	uart_printf(" Please adjust AIN2 value!\n");
	uart_printf(" The results of ADC are:\n");
	usConData=rADCDAT0&0x3FF;
			
	for(j=0;j<20;j++)								// sample and show data both by UART and leds
	{
		while(!(rADCCON & 0x8000));
		usConData=rADCDAT0&0x3FF;
		usEndData=usConData*3.3000/0x3FF;
		uart_printf(" %0.4f ",usEndData);
		
	
		delay(10000);
	}
	uart_printf(" end.\n");

}