Contoh loopback dari dan ke WAU serta pembentukan sinyal sinusoida

#include "NUC100Series.h"
#include "gpio.h"
#include "portinit.h" //lcd
#include "lcd.h"
#include "wau8822n.h"

# define PLLCON_SETTING      CLK_PLLCON_50MHz_HIRC
# define PLL_CLOCK           50000000
# define HCLK_DIV            1

#define MUTE_OFF(x)         PE->DOUT &= ~(1 << 14)
#define MUTE_ON(x)          PE->DOUT |=  (1 << 14)

//#define POOLING
#define LOOPBACK 1
#define MONOTOSTEREO 1
#define GAIN 1//50

#define SIN_SAMPLES     32
int32_t i32SinIdx = 0;
int16_t i16Sin[SIN_SAMPLES] = {
    0,3203,6284,9124,11612,13655,15172,16106,16423,16107,15172,13655,
    11613,9124,6284,3204,1,-3205,-6284,-9124,-11613,-13654,-15173,-16107,
    -16422,-16106,-15172,-13655,-11613,-9123,-6285,-3203
};

uint32_t g_u32TxValue;
uint32_t connect=TRUE;
void displayLCD(){

    //PC15=0;
    print_Line(0,   " Teknik Elektro ");
    printS(2*8+4,1*16,"Universitas"); //printS(x, y, char)
    printS(2*8,2*16,"Muhammadiyah");
    printS(3*8,3*16, "Purwokert0");
    connect=FALSE;

}

uint32_t spectrum[128];
volatile uint8_t ii=0;
extern void wau(void){
    uint8_t i;
    for(i=0;i<128;i++){
        spectrum[i]=0;
    }


    SYS_UnlockReg(); // Unlock protected registers
    CLK_EnableXtalRC(CLK_PWRCON_XTL12M_EN_Msk | CLK_PWRCON_OSC10K_EN_Msk ); // Enable HXT external 12MHz cyrstal
    CLK_SetCoreClock(50000000);    //  Set HCLK frequency 50MHz
    SYS_LockReg(); // Lock protected registers

    Port_Init(SPI3PORT);
    init_LCD();
    clear_LCD();

    //I2C - I2S WAU8822 codec
    WAU8822_Config();

    GPIO_SetMode(PE, BIT14, GPIO_PMD_OUTPUT);
    PE14=0;  //PHone OUT Enable (NUC-LB-140)

#ifdef POOLING
    //uint32_t u32Tmp;

    //open I2S function
    //st.u32SampleRate     = 16000;
    //st.u8WordWidth       = I2S_DATABIT_16;
    //st.u8AudioFormat     = I2S_STEREO;
    //st.u8DataFormat      = I2S_FORMAT_I2S;
    //st.u8Mode            = I2S_MODE_SLAVE;
    //st.u8TxFIFOThreshold = I2S_FIFO_TX_LEVEL_WORD_0;
    //st.u8RxFIFOThreshold = I2S_FIFO_RX_LEVEL_WORD_8;//SMP_ONE
    I2S_Open(I2S,I2S_MODE_MASTER,32000,I2S_DATABIT_16,I2S_STEREO,I2S_FORMAT_I2S);

    // Set MCLK and enable MCLK
    I2S_EnableMCLK(I2S,6000000);

    while(1)
    {

            if((I2S->STATUS & I2S_STATUS_TXFULL_Msk) == 0)
            {
                u32Tmp = i16Sini[i32SinIdxi];
                u32Tmp &= 0xFFFFUL;
                //u32Tmp |= u32Tmp << 16;  //duplicate it to stereo to Tx FIFO
                I2S->TXFIFO = u32Tmp;
                i32SinIdxi++;
                if(i32SinIdxi >= SIN_SAMPLESi)
                    i32SinIdxi = 0;

            }

    }
#else

    //interrupt
    I2S_Open(I2S,I2S_MODE_SLAVE,32000,I2S_DATABIT_16,I2S_STEREO,I2S_FORMAT_I2S);
    I2S_EnableMCLK(I2S,12000000);

    I2S_EnableInt(I2S,I2S_IE_RXTHIE_Msk );
    NVIC_EnableIRQ(I2S_IRQn);

    GPIO_SetMode(PC,BIT12,GPIO_PMD_OPEN_DRAIN);PA12=1;
    GPIO_SetMode(PC,BIT14,GPIO_PMD_OPEN_DRAIN);

    if(PE15==1) displayLCD();

    while(1)
    {
        CLK_SysTickDelay(1000000);
        if(PE15==0)
        {
            if(connect==FALSE) {
                clear_LCD();
                print_Line(0,   "Line-In Sound OK");
            }
            PC12 ^= 1;  //in LIN connected
            connect=TRUE;


        }else{
            if(connect){displayLCD();}

        }


    }
#endif
}

void I2S_IRQHandler(void)
{
    uint32_t u32Tmp=0;
    //unit32_t s =

    /* Fill sin samples to I2S until Tx FIFO full */
    while((I2S->STATUS & I2S_STATUS_TXFULL_Msk) == 0)
    {

#if LOOPBACK // Just loop Rx FIFO to Tx FIFO
        u32Tmp = I2S->RXFIFO;
        I2S->TXFIFO = (u32Tmp*GAIN);
#elif MONOTOSTEREO // Mono data in Rx FIFO and duplicate it to stereo to Tx FIFO
        u32Tmp = I2S->RXFIFO*GAIN & 0xFFFF0000UL;
        u32Tmp |= u32Tmp >> 16;
        I2S->TXFIFO = u32Tmp;

#else // Output Sin Wave
        u32Tmp = i16Sin[i32SinIdx];
        u32Tmp &= 0xFFFFUL;
        u32Tmp |= u32Tmp << 16;
        I2S->TXFIFO = u32Tmp;
        i32SinIdx++;
        if(i32SinIdx >= SIN_SAMPLES)
            i32SinIdx = 0;
#endif
    }
    ii = u32Tmp;
    PC->DOUT ^= (1 << 14);
}