DSP5509的ADC实验

1. 本次使用esay5509开发板，具体做这个板子叫做大道科技。

2. 5509有2个ADC的输入引脚，就是2个采集通道

3. 看下ADC的寄存器

4. 看下代码中怎么引用ADC的寄存器的，这种写法很少用，但是在DSP中很常见的。

ioport unsigned int *ADCCTL1=(unsigned int *)0x6800;
ioport unsigned int *ADCDATA1=(unsigned int *)0x6801;
ioport unsigned int *ADCCLKDIV1=(unsigned int *)0x6802;
ioport unsigned int *ADCCLKCTL1=(unsigned int *)0x6803;
#define ADCCTL (*ADCCTL1)
#define ADCDATA (*ADCDATA1)
#define ADCCLKDIV (*ADCCLKDIV1)
#define ADCCLKCTL (*ADCCLKCTL1) 

5. 主程序比较简单

main()
{
    int i;
    unsigned int uWork;
    
    EnableAPLL();

    InitADC();
    PLL_Init(132);
    while ( 1 )
    {
        for ( i=0;i<256;i++ )
        {
            ADCCTL=0x8000;    // 启动AD转换，通道0
            do
            {
                uWork=ADCDATA;
            } while ( uWork&0x8000 );
            nADC0[i]=uWork&0x0fff;
        }
        for ( i=0;i<256;i++ )
        {
            ADCCTL=0x9000;    // 启动AD转换，通道1
            do
            {
                uWork=ADCDATA;
            } while ( uWork&0x8000 );
            nADC1[i]=uWork&0x0fff;
        }
        asm( " nop");        // break point 在这里设断点
    }
}

void InitADC()
{
    ADCCLKCTL=0x23; // 4MHz ADCLK
    ADCCLKDIV=0x4f00;
}

6. 在程序中注意到一个细节，怎么直接给寄存器赋值的，看下面*( ioport volatile unsigned short* )0x1f00 = 4;这种写法很重要，一定要掌握。

void EnableAPLL( )
{
    /* Enusre DPLL is running */
    *( ioport volatile unsigned short* )0x1f00 = 4;
    wait( 25 );
    *( ioport volatile unsigned short* )0x1f00 = 0;
    // MULITPLY
    *( ioport volatile unsigned short* )0x1f00 = 0x3000;
    // COUNT
    *( ioport volatile unsigned short* )0x1f00 |= 0x4F8;
    wait( 25 );
    //*( ioport volatile unsigned short* )0x1f00 |= 0x800
    // MODE
    *( ioport volatile unsigned short* )0x1f00 |= 2;
    wait( 30000 );
    // APLL Select
    *( ioport volatile unsigned short* )0x1e80 = 1;
    // DELAY
    wait( 60000 );
}