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LPC3250 DMA Help

eswar g

Hi all

i posted before this problem. now im posting with some improvement.

My Source is Memory and Destination is peripheral. I have configured the DMA as
- 32bit wide Source and 32bit Destination.
- 8-byts source burst
- 8-byte Destination burst
- Transfer size as 8 bytes

GPDMA_CH0_CTRL     =0x85492008;    // 32 bit wide 8byte


I’m filling the memory with bytes and sending to the Peripheral (HSUART2TX).

Tx_Buffer_485[0]=0x37;
        Tx_Buffer_485[1]=0x36;
        Tx_Buffer_485[2]=0x35;
        Tx_Buffer_485[3]=0x34;
        Tx_Buffer_485[4]=0x33;
        Tx_Buffer_485[5]=0x32;
        Tx_Buffer_485[6]=0x31;
        Tx_Buffer_485[7]=0x30;


I’m getting data as 4spaces and 4 characters. ( 3210)
I tried all the way but unable to get the bytes.
My aim is to transfer t 8 bytes when I enable DMA Channel. (76543210).

here i'm attaching my main file also

int main(void)
{
        unsigned long pt;
        init_HSUART2();
        Init_DMA0();
   while(1)
      {
        Tx_Buffer_485[0]=0x37;
        Tx_Buffer_485[1]=0x36;
        Tx_Buffer_485[2]=0x35;
        Tx_Buffer_485[3]=0x34;
        Tx_Buffer_485[4]=0x33;
        Tx_Buffer_485[5]=0x32;
        Tx_Buffer_485[6]=0x31;
        Tx_Buffer_485[7]=0x30;

/************************* arranged key to enable dma after filled the busser*************/
/**************************for testing only***********************************************/
P2_MUX_SET=P2_MUX_SET|0x08;
        P2_DIR_CLR=0x00000040;  // Making GPIO_05 as input pin
         while((P2_INP_STATE&0x00000040)==0x00000040);
                while((P2_INP_STATE&0xFFFFFFBF)==0xFFFFFFBF);
/*****************************************************************************************/
        GPDMA_SOFT_BREQ |=0x00000080;           // HSUART 2 TX  Selected

         }


}

Here is the DMA Initialization

void Init_DMA0(void)
{
        DMACLK_CTRL             |=0x00000001;           // enable all DMA Clocks
        GPDMA_CH0_SRC    =(unsigned long)&Tx_Buffer_485[0];
        GPDMA_CH0_DEST   =0x40018000;
        GPDMA_CH0_LLI    =0x00000000;
        GPDMA_CH0_CTRL  =0x85492008;            // 32 bit wide 8byte
        GPDMA_CONFIG     |=0x00000001;          // Enable DMA Controller
        GPDMA_CH0_CFG    |=0x000009C1;          // memory  to Peripheraltrnasaction


}

Please help me with this. Its very urgent

Thanks
Eswar

0