【求助】SPI(DMA方式)，代码分析！

f56007

【求助】SPI(DMA方式)，代码分析！ [复制链接]

void SPI_Init()
{
//----------- IMPORTANT: By default, the internal clock is disabled. To configure the controller ------
// we must first enable it.
StartSPIClock();
// ----------------------Configure the GPIO pins for SPI mode -------------------------------
//
// nSPICS0 (chip select) = GPG2
// SPICLK0 (SPI clock) = GPE13
// SPIMOSI0 (SPI output data) = GPE12
// SPIMISO0 (SPI input data) = GPE11
s2440IOP->rGPGCON &=~(0x3<<4);
s2440IOP->rGPGCON |=(0x1<<4); //GPG2 [OUTPUT]
s2440IOP->rGPGUP &=~(0x1<<2); //enable pullup
s2440IOP->rGPECON &= ~((3<<26) | (3<<24)|(3<<22));
s2440IOP->rGPECON |= ((0x2<<26)|(0x2<<24)|(0x2<<22));
s2440IOP->rGPEUP |= (0x7<<11);
//SPI register init
s2440SPIreg->rSPCON0=(0<<5)| //(SMOD) ; 10 = DMA mode ; 01 = interrupt mode
(1<<4)| //clock enable
(1<<3)| //(MSTR) :1 = master mode
(SPI_CLOCK_POLARITY<<2)| //(CPOL) Determine an active high or active low clock;
(1<<1)| //(CPHA) format B
(0); //TAGD
s2440SPIreg->rSPPIN0=(0<<2)|(1<<1)|(0);
// RETAILMSG(DEBUG_ZONE,(TEXT("SPI_Init__rSPSTA0={0x%x}\r\n"),s2440SPIreg->rSPSTA0));
SetSPIClockRate(CLK_RATE_SIXTY4);
}

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void DmaWriteData(/*const unsigned char *buffer,*/DWORD dwNumBytes)
{
RETAILMSG(1,(TEXT(">>>>DmaWriteData \r\n")));
RETAILMSG(DEBUG_ZONE,(TEXT("dwNumBytes=%d\r\n"),dwNumBytes));
unsigned int ct=0;
int delay_count=0,i=0,waitCount=0;
for(ct=0;ct<(dwNumBytes);ct+=2)
RETAILMSG(DEBUG_ZONE,(TEXT("%dth:{0x%x,0x%x}\r\n"),ct/2 ,*(pDmaBuffer+ct),*(pDmaBuffer+ct+1)));
RETAILMSG(DEBUG_ZONE,(TEXT("DMA__Current source address before tx ={0x%x}\r\n"),s2440DMA->rDCSRC1));
//------------------------------ wait for DMA to complete.-------------------------------
while((s2440DMA->rDSTAT1 & 0xfffff)!=0)
{
RETAILMSG(1,(TEXT("DMA is busy now! 1th\r\n")));
};
if((s2440DMA->rDSTAT1 & 0x300000)==0)
{
RETAILMSG(1,(TEXT("DMA is ready now! 1th\r\n")));
}
//-------------------------------- Configure the DMA SPI mode -------------------------
SpiInitDma();
//nss0 low
s2440IOP->rGPGCON &=~(0x3<<4);
s2440IOP->rGPGCON |=(0x3<<4);
//s2440IOP->rGPGUP &=~(0x1<<2); //enable pullup
s2440IOP->rGPGDAT &=~(1<<2);
SPI_CS_High();
SPI_CS_Low();
s2440DMA->rDISRC1 =(int)(SPI_BUF_PHYS_BASE); //源地址 :DMA对应物理地址
s2440DMA->rDISRCC1 &= ~(0x3);
// Source is system bus（内存块中）, increment addr（每次数据传送之后地址递增）
//---------------- Initialize the DMA channel to send data over the SPI bus --------------------
s2440DMA->rDIDST1 = (int)D_ADDR; // 要传送的目的地址，这里应该是SPI的数据数据地址（SPTDAT0）
s2440DMA->rDIDSTC1 = //(CHK_INT<<2)| //中断触发模式
(1<<1)| // (1); // fixed addr ，
//-------- Configure the DMA channel's transfer characteristics: handshake, sync PCLK, ----------
// single tx, single service, no auto-reload, byte, tx count
s2440DMA->rDCON1 = (1<<31)| //Handshake mode ,
(0<<30) | //while for those attached to APB system, it should be set to 0
//(1<<30) | //while for those attached to APB system, it should be set to 0
(0<<29) | // 决定DMA中断何时产生(i.e.CURR_TC becomes 0).
(0<<28) | // a unit transfer is performed. 数据一直传送直到TC为0
(1<<27) | //Whole service mode
#if HARD_TRIGGER
(0x3<<24) | //DMA request source is SPI
(1<<23) | //H/W request mode
#else
(0<<23) | //S/W request mode ,triggered by setting SW_TRIG
#endif
(1<<22) | //NO_DMA_AUTO_RELOAD
(0<<20) | //Data size to be transferred. ;BYTE
(dwNumBytes) ; //
RETAILMSG(1, (TEXT(" 1TH CURR_TC =%x.\r\n"),s2440DMA->rDSTAT1));
//------------------------------ wait for DMA to complete.-------------------------------
while((s2440DMA->rDSTAT1 & 0xfffff)!=0)
{
RETAILMSG(1, (TEXT(" ... CURR_TC =%x.\r\n"),s2440DMA->rDSTAT1));
RETAILMSG(1,(TEXT("DMA is busy now! 2th\r\n")));
};
//RETAILMSG(1, (TEXT(" CURR_TC =%d.\r\n"),s2440DMA->rDSTAT1));
//---------------------------------Trigger DMA---------------------------------------
//Note. This bit should not be changed manually during DMA operations
s2440DMA->rDMASKTRIG1 &= ~(1<<2);
// s2440DMA->rDMASKTRIG1 |= (1<<1); //0110
s2440DMA->rDMASKTRIG1 = 0x006; //0110
while((s2440DMA->rDSTAT1 & 0xfffff)!=0)
{
RETAILMSG(1, (TEXT(" DMA_CURR_TC =%x.\r\n"),s2440DMA->rDSTAT1));
};
#if 1
RETAILMSG(DEBUG_ZONE,(TEXT("DMA__rDSTAT1.={0x%x}\r\n"),s2440DMA->rDSTAT1));
//[21:20] 0:ready,1:busy [19:0] Current value of transfer count
RETAILMSG(DEBUG_ZONE,(TEXT("SPI__rSPTDAT0={0x%x}\r\n"),s2440SPIreg->rSPTDAT0));//输出为0x8，说明数据是传递到SPTDAT端了
RETAILMSG(DEBUG_ZONE,(TEXT("SPI__rSPSTA0={0x%x}\r\n"),s2440SPIreg->rSPSTA0));
//[0] 0 = not ready ;1 = data Tx/Rx ready;
//[1] 0 = not detect 1 = multi master error detect
//[2] This flag is set if the SPTDATn is written or SPRDATn is read whilea transfer is in progress and cleared by reading the SPSTAn. 0 = not detect 1 = collision error detect
RETAILMSG(DEBUG_ZONE,(TEXT("DMA__Current source address ={0x%x}\r\n"),s2440DMA->rDCSRC1));
RETAILMSG(DEBUG_ZONE,(TEXT("DMA__Current destination address={0x%x}\r\n"),s2440DMA->rDCDST1));
#endif
delay_count = 0;
while((s2440DMA->rDSTAT1 & 0xfffff)==0)
{
if( delay_count++ > DELAY_COUNT )
{
RETAILMSG(1, (TEXT(" timeout occurred while waiting to start DMA.\r\n")));
break;
}
}
SPI_CS_High();
RETAILMSG(1,(TEXT("<<<<<
}

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帮我分析下！
情况是：我用SPI（dma mode）来将数据传递到外设，
但现在我抓 SPIMISO 、SPIMOSI 、SPICLK的波形抓不到！
SPLCLK有时候会出来

不知道是什么没有配置好；

源地址：SPI_BUF_PHYS_BASE 是我在对应的是我在config.bib中的地址
目的地址：D_ADDR 是SPTDAT0 0x59000010
[code]

我打打印信息：
DMA__rDSTAT1.={0x0}
SPI__rSPTDAT0={0x8}
SPI__rSPSTA0={0x1}
DMA__Current source address ={0x3005004c}
DMA__Current destination address={0x59000010}
  timeout occurred while waiting to start DMA.

我通过for循环，连续写5组数据进去,进行测试的

tiantiantian

jinwancai

如果我改变数据的末尾的值，那么SPI的数据输出端SPI__rSPTDAT0={0x8} 得值也会变，
而且输出TC的值，也是预定值，
-------说明DMA收到了SPI的请求，并已经装载TC值，而且，所有的数据都已传到SPI的输出端

但现在用示波器却抓不到波形？

thelastzen

量过电路是通的吗？通常这种错误是由最简单的问题引起的，先确认电路没问题再说

trueve

同意楼上的，如果电路通，看看波形是否正确等

5ilxt

电路通？这个不存在问题！
我直接测试的是GPIO口，所以只要IO复用配置好，就OK了！

liukaiyue

wait ....

jhqianyuping

SPI
一、如果采用中断方式，那么中断时在什么情况下被触发的？
二、如果采用查询方式，应该怎么实现，
1、配置SPI为查询方式
2、检测什么信号？
3、写数据？

ivanband

一、如果采用中断方式，那么中断时在什么情况下被触发的？SPI接收或发送都可以产生中断的

二、如果采用查询方式，应该怎么实现，
? ? 1、配置SPI为查询方式
? ? 2、检测什么信号？读相应的寄存器
? ? 3、写数据？就直接写，然后确定发送完毕

0211liucheng

看下,mark

【求助】SPI(DMA方式)，代码分析！ [复制链接]

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