新聞中心

EEPW首頁(yè) > 嵌入式系統(tǒng) > 設(shè)計(jì)應(yīng)用 > s3c6410 DMA 實(shí)現(xiàn)(入門級(jí))

s3c6410 DMA 實(shí)現(xiàn)(入門級(jí))

作者: 時(shí)間:2016-11-11 來(lái)源:網(wǎng)絡(luò) 收藏
char src[200] = "abcdefghigklmn123456n";

char dest[200] = "kkkkn";

本文引用地址:http://m.butianyuan.cn/article/201611/316682.htm

void dma_init(void)
{
DMACConfiguration = 1; //開(kāi)總的DMA 使能
DMACC7SrcAddr = (int)src; //給源地址寄存器賦源地址
DMACC7DestAddr = (int)dest;//給目標(biāo)地址寄存器賦目的地址
DMACC7Control0 = 0x0c000000; //【26】【27】位置1,使源地址和目標(biāo)地址在發(fā)送后遞增
DMACC7Control1 = 0x64; //寫入拷貝的size;
DMACC7Configuration |= 1<<0; //開(kāi)channel7 DMA
}

main()

{

dma_init();
delay();
my_puts("----------------n");
my_puts(src);
my_puts(dest);

}

之后打印出的src和dest內(nèi)容相同

6410手冊(cè)中操作DMA的編程步驟:

Steps to program a DMA channel:

1. Decide whether use secure DMAC(SDMAC) or general DMAC(DMAC). In order to use general DMAC,

disable secure DMA control register(SDMA_SEL) of system controller. (Reset value is SDMAC)

2. Select a free DMA channel with the priority needed. Where DMA channel 0 has the highest priority and DMA

channel 7 the lowest priority.

DMACCXCONFIGURATION

DMACC7Configuration 【0】位值1

3. Clear any pending interrupts on the channel to be used by writing to the DMACIntTCClr and DMACIntErrClr

registers. The previous channel operation might have left interrupts active.

4. Write the source address into the DMACCxSrcAddr register.

5. Write the destination address into the DMACCxDestAddr register.

6. Write the address of the next LLI into the DMACCxLLI register. If the transfer comprises of a single packet of

data then must be written into this register.

Offset Contents

Next LLI address Source Address for next transfer

Next LLI address + 0x04 Destination Address for next transfer

Next LLI address + 0x08 Next LLI address for next transfer

Next LLI address + 0x0C DMACCxControl0 data for next transfer

Next LLI address + 0x10 DMACCxControl1 data for next transfer

7. Write the control information into theDMACCxControlregister.

DMACCxControl0

DMACCxControl1 transfer size

8. Write the channel configuration information into the DMACCxConfiguration register. If the Enable bit is set

then the DMA channel is automatically enabled.



關(guān)鍵詞: s3c6410DM

評(píng)論


技術(shù)專區(qū)

關(guān)閉