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msp430 SD CARD-> DAC12 using DMA Transfer

Started by goode January 26, 2010
Dear All,
I have a small problem. 
I am trying to play a wave file from my SD card. I am not using FAT i am
just reading raw data from the card.
I want to do this using DMA transfer.

I wrote the following code, but this does not output the wave file from the
DAC.
Does anyone have any idea, what i should do?

Best Regards
Kerem

#include  <msp430x26x.h>
#include <hal_hardware_board.h>
#include <mmc.h>
#include <stdio.h>
#include <intrinsics.h>
#include <stdint.h>
//__no_init volatile unsigned long DMA0SZ @ DMA0SZ_;


unsigned long cardSize = 0;
unsigned char status = 1;
unsigned int timeout = 0;
int i = 0;
int k= 0;
int kerem = 0;
int filesize = 0;
int* filePtr = NULL;
int sector = 0;

unsigned char buffer[512];

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                 // Stop watchdog timer
  DCOCTL = CALDCO_16MHZ;
  BCSCTL1 = CALBC1_16MHZ;
  BCSCTL2 = SELM_0 | DIVS_2;
  //P1DIR |= 0x01;                            // Set P1.0 to output
direction
  P1DIR = BIT0 | BIT4;                            // Set P1.0 to output
direction
  P2DIR = BIT0 ;
  P5DIR = BIT4 | BIT5;
  P1SEL = BIT4;
  P2SEL = BIT0;
  P5SEL = BIT4 | BIT5;  
  
  P6DIR = BIT6 ;
  P6SEL = BIT6;
  
  ADC12CTL0 = REFON;
  
  DAC12_0CTL = DAC12SREF_0 | DAC12RES | DAC12LSEL_2 | DAC12IR | DAC12AMP_7
| DAC12CALON;

  while (DAC12_0CTL & DAC12CALON != 0){
  }
  DMACTL0 =DMA0TSEL_5;
  DMACTL1 = 0;
  

  DMA0CTL = DMADT_0 | DMADSTINCR_0 | DMASRCINCR_3 | DMADSTBYTE |
DMASRCBYTE;
  
    //Initialisation of the MMC/SD-card
  while (status != 0)                       // if return in not NULL an
error did occur and the
                                            // MMC/SD-card will be
initialized again 
  {
    status = mmcInit();
    timeout++;
    if (timeout == 150)                      // Try 50 times till error
    {
      //printf ("No MMC/SD-card found!! %x\n", status);
      break;
    }
  }

  while ((mmcPing() != MMC_SUCCESS));      // Wait till card is inserted

  // Read the Card Size from the CSD Register
  cardSize =  mmcReadCardSize();
  
  mmcReadSector(sector, buffer);
  
  __data16_write_addr((unsigned short) &DMA0SA,(unsigned long) buffer
+44);

                                            // Source block address
  __data16_write_addr((unsigned short) &DMA0DA,(unsigned long)
&DAC12_0DAT);
  
  
  DMA0SZ = 64;
  
  TACCR0 = 1;
  TACCR1 = 1;
  TACCTL1 = OUTMOD_7;
  
  DMA0CTL = DMA0CTL | DMAEN | DMAIE;
  DAC12_0CTL = DAC12_0CTL | DAC12ENC | DAC12IFG ;

  
  TACTL = TASSEL_1 | ID_0 | MC_1 | TACLR;

__enable_interrupt();
  for (;;)
  {

    P1OUT ^= 0x01;                          // Toggle P1.0 using
exclusive-OR
   
   i = 50000;                              // Delay
    do (i--);
    while (i != 0);
  }
}
#pragma vector = DMA_VECTOR
__interrupt void DMA_int(void)
{

	sector++;
	
	mmcReadSector(sector, buffer);
  
  
  	__data16_write_addr((unsigned short) &DMA0SA,(unsigned long) buffer);
  //__data16_write_addr((unsigned short) &DMA0SA,(unsigned long) wave);
                                            // Source block address
  __data16_write_addr((unsigned short) &DMA0DA,(unsigned long)
&DAC12_0DAT);
  

  DMA0SZ = 512;
  DMA0CTL |= DMAEN | DMAIE;

  DAC12_0CTL = DAC12_0CTL | DAC12ENC | DAC12IFG ;
  
  
}


	   
					
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