Streaming DMA UART

i try to use your code successfull .

After i use structure data instead buffer of bytes .

So in this case the dma continually send butes and my pc

became crazy .

Then i try to fill your buffer from my data structure but the same occur .

http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/sad.gif

Very strange

In pc side i&#39;m using vc#.net with a rs232 dll .

I post my code

# include <stdio.h># include <stdlib.h># include "sys/alt_dma.h"# include "system.h"# include "alt_types.h"# include "dma_test.h"

typedef struct conn{

alt_u16 data1;

alt_u16 data2;

alt_u16 data3;

alt_u16 data4;

}Master;

alt_u8 buffer[16] __attribute__ ((section (".ext_ram")));

Master data;// __attribute__ ((section (".ext_ram")));

static volatile int dma_complete = 0;

void dma_done (void* handle)

{

dma_complete = 1;

}

int main(int argc, char* argv[], char* envp[])

{

int rc;

//buffer[0] = 0x30;

//buffer[1] = 0x31;

//buffer[2] = 0x32;

//buffer[3] = 0x33;

data.data1=10;

data.data2=20;

data.data3=30;

data.data4=40;

data.data5=50;

data.data6=60;

data.data7=70;

data.data8=80;

alt_u8 i;

alt_u8* pDati;

alt_u8 size = sizeof(data);

pDati = (alt_u8*)&data; //Point the first byte of my structure

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

{

buffer[i] = *(pDati+i);

}

void* tx_data = (void*) &buffer[0];//data;//&buffer[0];

printf("Hello from Nios II!\n");

printf("size:%u\r",size);

alt_dma_txchan tx;

if ((tx = alt_dma_txchan_open("/dev/dma_0")) == NULL)

{

printf("Failed to open device!\n");

exit(1);

}

alt_dma_txchan_ioctl(tx, ALT_DMA_SET_MODE_8, NULL);

alt_dma_txchan_ioctl(tx, ALT_DMA_RX_STREAM_ON, (void*) UART_0_BASE+1);

dma_complete = 0;

if ((rc = alt_dma_txchan_send (tx, tx_data, 16, dma_done, NULL)) < 0 )

{

printf("Failed to post transmit request!, reason = %i\n", rc);

exit(1);

}

while (!dma_complete);

alt_dma_txchan_close (tx);

printf("Transaction Complete!\n");

printf(" :%u,%u,%u,%u,%u,%u,%u,%u\r",buffer[0],buffer[1],buffer[2],buffer[3],buffer[4],buffer[5],buffer[6],buff

er[7]);

return 0;

}

The last printf i use prints the correct value of 16 bytes buffer .

But the pc receive totally differents datas.

Printf shows to me correct data in buffer :

buffer[0]=10

buffer[1]=0

buffer[2]=20

buffer[3]=0

............

in the pc i recevice

58-58-10-30-58-58-10-30-58-58-10-30-58-58-10-30

Do you have some idea?

ciao

walter