File content as of revision 0:6d43d111bdc1:

#include "mbed.h"
#include "i2s.h"
#include "type.h"
#include "dma.h"

extern volatile uint8_t *I2STXBuffer, *I2SRXBuffer;
extern volatile uint32_t I2SReadLength;
extern volatile uint32_t I2SWriteLength;
extern volatile uint32_t I2SRXDone, I2STXDone;
extern volatile uint32_t I2SDMA0Done, I2SDMA1Done;

DigitalOut myled(LED1);


int main() {
    uint32_t i;
    /* Configure temp register before reading */
    for ( i = 0; i < BUFSIZE; i++ ) {	/* clear buffer */
        I2STXBuffer[i] = i;
        I2SRXBuffer[i] = 0;
    }

    if ( I2SInit() == FALSE ) {	/* initialize I2S */
        while ( 1 );			/* Fatal error */
    }

#if I2S_DMA_ENABLED
    /* USB RAM is used for test.
    Please note, Ethernet has its own SRAM, but GPDMA can't access
    that. GPDMA can access USB SRAM and IRAM. Ethernet DMA controller can
    access both IRAM and Ethernet SRAM. */
    LPC_SC->PCONP |= (1 << 29);	/* Enable GPDMA clock */

    LPC_GPDMA->DMACIntTCClear = 0x03;
    LPC_GPDMA->DMACIntErrClr = 0x03;

    LPC_GPDMA->DMACConfig = 0x01;	/* Enable DMA channels, little endian */
    while ( !(LPC_GPDMA->DMACConfig & 0x01) );

    /* on DMA channel 0, Source is memory, destination is I2S TX FIFO,
    on DMA channel 1, source is I2S RX FIFO, Destination is memory */
    /* Enable channel and IE bit */
    DMA_Init( 0, M2P );
    LPC_GPDMACH0->DMACCConfig |= 0x18001 | (0x00 << 1) | (0x05 << 6) | (0x01 << 11);
    DMA_Init( 1, P2M );
    LPC_GPDMACH1->DMACCConfig |= 0x08001 | (0x06 << 1) | (0x00 << 6) | (0x02 << 11);

    NVIC_EnableIRQ(DMA_IRQn);

    I2SStart();

    LPC_I2S->I2SDMA2 = (0x01<<0) | (0x08<<8);	/* Channel 2 is for RX, enable RX first. */
    LPC_I2S->I2SDMA1 = (0x01<<1) | (0x01<<16);/* Channel 1 is for TX. */

    /* Wait for both DMA0 and DMA1 to finish before verifying. */
    while ( !I2SDMA0Done || !I2SDMA1Done );
#else
    /* Not DMA mode, enable I2S interrupts. */
    /* RX FIFO depth is 1, TX FIFO depth is 8. */
    I2SStart();
    LPC_I2S->I2SIRQ = (8 << 16) | (1 << 8) | (0x01 << 0);

    while ( I2SWriteLength < BUFSIZE ) {
        while (((LPC_I2S->I2SSTATE >> 16) & 0xFF) == TXFIFO_FULL);
        LPC_I2S->I2STXFIFO = I2STXBuffer[I2SWriteLength++];
    }

    I2STXDone = 1;
    /* Wait for RX and TX complete before comparison */
    while ( !I2SRXDone || !I2STXDone );
#endif

    /* Validate TX and RX buffer */
    for ( i=1; i<BUFSIZE; i++ ) {
        if ( I2SRXBuffer[i] != I2STXBuffer[i-1] ) {
            while ( 1 );	/* Validation error */
        }
    }
    return 0;
}