URGENT: Peripheral to Memory DMA Transaction

This is my code: I dunno why it wont work... the data cant be written into sdram.

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#include "io.h"# include <stdio.h># include <unistd.h># include <sys/alt_dma.h># include "altera_avalon_dma_regs.h"# include "altera_avalon_pio_regs.h"# include "alt_types.h"# include "system.h"

//#include "sys/alt_timestamp.h"

int main()

{

int i;

int a=100;

unsigned int dst = SDRAM_BASE + 0x400000;

IOWR_ALTERA_AVALON_DMA_STATUS(DMA_BASE, 0x00);

for(i=0;i<100;i++)

{

IOWR(PERIPHERAL_0_BASE, 0, 30);

IOWR_ALTERA_AVALON_DMA_RADDRESS(DMA_BASE, PERIPHERAL_0_BASE);

IOWR_ALTERA_AVALON_DMA_WADDRESS(DMA_BASE,dst);

IOWR_ALTERA_AVALON_DMA_LENGTH(DMA_BASE,100);

}

IOWR_ALTERA_AVALON_DMA_CONTROL(DMA_BASE,0X199);

for(i=0;i<100;i++)

{

printf("%d\n", IORD(dst, i));

}

}

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