adc.c

arm9.rar

//====================================================================
// File Name : Adc.c
// Function  : S3C2410 ADC Test 
// Program   : Kang, Weon Tark 
// Date      : May 22, 2002
// Version   : 0.0
// History
//   0.0 : Programming start (March 29,2002) -> KWT
//         ADC Test                          -> May 15, 2002 SOP
//====================================================================
#include "def.h"
#include "2410addr.h"
#include "config.h"
#include "board.h"
#include "utils.h"
#include "adc.h"

#define REQCNT 100              //May 08, 2002 SOP
#define ADC_FREQ 2500000
//#define ADC_FREQ   1250000
//#define LOOP 1
#define LOOP 10000

void __irq DMA0_Done(void);	//Declare Prototype function

int ReadAdc(int ch);	        //Return type is int, Declare Prototype function
volatile U32 preScaler;

//==================================================================================
void Test_Adc(void) 
{
    int a0=0; //Initialize variables
    U32 rADCCON_save = rADCCON;
    
   	printf( "ADC INPUT Test, press ESC key to exit !\n" ) ;

    preScaler = ADC_FREQ;
    printf("ADC conv. freq. = %dHz\n",preScaler);
    preScaler = GetMasterClock()/ADC_FREQ -1;               //PCLK:50.7MHz
    
    printf("PCLK/ADC_FREQ - 1 = %d\n",preScaler);
    
    while( getkey() != ESC_KEY )
    {
	    a0=ReadAdc(0);

	    printf( "AIN0: %04d\n", a0 );
		Delay( 80 ) ;
    }
    
    //rADCCON=(0<<14)|(19<<6)|(7<<3)|(1<<2);  //stand by mode to reduce power consumption
    rADCCON = rADCCON_save;
    printf("\nrADCCON = 0x%x\n", rADCCON);
}

//==================================================================================		
int ReadAdc(int ch)
{
    int i;
    static int prevCh=-1;

    rADCCON = (1<<14)|(preScaler<<6)|(ch<<3);	//setup channel

    if(prevCh!=ch)
    {
	rADCCON = (1<<14)|(preScaler<<6)|(ch<<3);   //setup channel
	for(i=0;i<LOOP;i++);	//delay to set up the next channel
	prevCh=ch;
    }
    rADCCON|=0x1;   //start ADC

    while(rADCCON & 0x1);	//check if Enable_start is low
    while(!(rADCCON & 0x8000));	//check if EC(End of Conversion) flag is high

    return ( (int)rADCDAT0 & 0x3ff );
}

//==================================================================================
volatile char end_test;

void Test_DMA_Adc(void)
{
    unsigned int *dst,*tmp,i;
    //int key;
    U32 rADCCON_save = rADCCON;
    U32 rTCFG0_save = rTCFG0;
    U32 rTCFG1_save = rTCFG1;
    U32 rTCON_save  = rTCON;
    
    end_test=0;

    pISR_DMA0=(unsigned)DMA0_Done;	//Regist interrupt service routine
    rINTMSK &= ~(BIT_DMA0);		//Clear int mask bit. 

    printf("Test of the 'Start by read' in ADC block.\n");
    printf("Change the voltage of AIN0..(Sampling 100)\n");

    dst = (unsigned int *)0x31000000;	//Non-cacheable Area
    tmp = dst;
    for(i=0;i<REQCNT;i++)
	*tmp++=i;

    /***ADC init***/
    preScaler = GetMasterClock()/ADC_FREQ -1;
    rADCCON=(1<<14)|(preScaler<<6)|(0<<3)|0x2;	//normal,ADCPRS,AIN0,enable start by read

    /***DMA0 init***/
    rDISRC0=0x5800000c;		// rADCDAT0
    rDISRCC0=(1<<1)|(1<<0);	// APB,Fixed
    rDIDST0=(int)dst;		// dst
    rDIDSTC0=(0<<1)|(0<<0);	// AHB,++
    rDCON0=(1U<<31)|(0<<30)|(1<<29)|(0<<28)|(0<<27)|(3<<24)|(1<<23)|(1<<22)|(2<<20)|REQCNT;
	    //handshake, sync PCLK, TC int, single tx, single service, Timer, Timer(H/W) request, 
	    //auto-reload off, word, REQCNT
    rDMASKTRIG0=(0<<2)|(1<<1)+0;    //no-stop, DMA0 channel on, no-SW trigger 
/*
    for(i=0;i<5;i++)
	printf("%d:0x%x\n",i, *(int *)(0x4b000000+i*4) );
*/
    /***Timer0 init***/
    rTCON &= ~0x1f;
    rTCFG0 &= ~0xff;
    rTCFG1 &= ~((0xf<<20)|(0xf));
    rTCFG0 |= 255;		//prescaler0=255
//    rTCFG0=0;		//prescaler0=0
    rTCFG1 |= (1<<20) | 3;	//Timer0 DMA, div=16 
//    rTCNTB0=4900;	//(1/(50MHz/255/16))*4900=(1/(12254.9) * 4900)=0.0000816 * 4900 = 0.401 sec 
    rTCNTB0=1226;	//0.0000816 * 1226 = 0.1 sec
//    rTCNTB0=2452;	//0.0000816 * 2452 = 0.2 sec    
//    rTCNTB0=1716;	//0.0000816 * 1716 = 0.14 sec    
//    rTCNTB0=10;	        //(1/(50MHz/1/16))*10=(1/(3125000)*10)=0.0000003*10 = 0.000003 sec
//    rTCNTB0=100;	        //0.0000003*100 = 0.00003 sec    
//    rTCNTB0=2000;	        //(1/(50MHz/1/16))*2000=(1/(3125000)*2000)=0.0000003*2000 = 0.0006 sec
	rTCON &= ~0x1f;
    rTCON |= 0xa;		//auto reload, manual update
    rTCON &= ~0x1f;
    rTCON |= 0x9;		//Start Timer0
    i = rADCDAT0;		//Read out dummy data and start first ADC operation

    while(!end_test);
    
   	rINTMSK |= BIT_DMA0;
    
    rTCON  = rTCON_save;
    rTCFG1 = rTCFG1_save;
    rTCFG0 = rTCFG0_save;
    rADCCON = rADCCON_save;

    tmp=dst;

    for(i=0;i<REQCNT;i++)
    {
	*tmp = (*tmp) & 0x3ff;
	tmp++;
    }

    for(i=0;i<REQCNT;i++)
        printf("%04d\n",*dst++);                   //May 08, 2002 SOP
//	printf("%02d=%04d\n",i,*dst++);
//	printf("%02d=0x%x\n",i,*dst++);

    //printf("0x%08x,0x%08x,0x%08x\n", rTCON, rTCFG0, rTCFG1);
    
    puts("press any key to continue...\n");
    getch();
}

//==================================================================================
void __irq DMA0_Done(void)
{
    ClearPending(BIT_DMA0);

	//rDMASKTRIG0 = 4;
    rTCON &= ~0x1f;		//Stop Timer0
    end_test=1;		//set end flag
}


static char title[] = "ADC实验";
static char tip[]   = "实验ADC模数转换,按ESC键返回";

//Test_Adc_Item 在 prog_entry.c 里被引用
TEST_PROGRAM_ITEM Test_Adc_Item = {
				(TEST_PROGRAM)Test_Adc, 	//入口地址
				title, 					//显示名称
				tip, 					//帮助或提示信息,可为NULL
				1};						//使用printf,puts,putch等函数时在LCD上也显示输出字符(串)

static char title1[] = "DMA方式的ADC实验";
static char tip1[]   = "通过DMA方式读取ADC转换的数据,按ESC键返回";

//Test_Adc_Item 在 prog_entry.c 里被引用
TEST_PROGRAM_ITEM Test_DMA_Adc_Item = {
				(TEST_PROGRAM)Test_DMA_Adc, 	//入口地址
				title1, 					//显示名称
				tip1,	 					//帮助或提示信息,可为NULL
				1};							//使用printf,puts,putch等函数时在LCD上也显示输出字符(串)