求助，我STM32F205采用DMA方式法的SPI发送数据，为什么始终不成功呢？我问题出在哪儿

丝带机 · 发表于 2014-12-31 15:09:39

以下是我的代码：
SPI初始化部分：

[mw_shl_code=c,true]void BSP_SPI_GPIO_Cfg(void) { SPI_InitTypeDef SPI_InitStruct; GPIO_InitTypeDef GPIO_InitStructure_SPI2_MISO; GPIO_InitTypeDef GPIO_InitStructure_SPI2_MOSI; GPIO_InitTypeDef GPIO_InitStructure_SPI2_SCK; GPIO_InitTypeDef GPIO_InitStructure_SPI2_SELN; /*********SPI IO口时钟配置************/ RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE); RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);////SCK RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);////MOSI/MISO GPIO /**********配置SPI 口的IO口功能************/ GPIO_PinAFConfig(GPIOC,GPIO_PinSource3,GPIO_AF_SPI2); //Port C Pin 3 is SPI2 MOSI GPIO_PinAFConfig(GPIOC,GPIO_PinSource2,GPIO_AF_SPI2); //Port C Pin 2 is SPI2 MISO GPIO_PinAFConfig(GPIOB,GPIO_PinSource10,GPIO_AF_SPI2); //Port B Pin 10 is SPI2 SCK GPIO_PinAFConfig(GPIOC,GPIO_PinSource7,GPIO_AF_SPI2); //Port A Pin 2 is SPI2 SELN /* Configure SPI SELN */ GPIO_InitStructure_SPI2_SELN.GPIO_Pin = GPIO_Pin_7; GPIO_InitStructure_SPI2_SELN.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure_SPI2_SELN.GPIO_Mode = GPIO_Mode_OUT; //GPIO_Mode_AF GPIO_InitStructure_SPI2_SELN.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure_SPI2_SELN.GPIO_PuPd = GPIO_PuPd_NOPULL; GPIO_Init(GPIOC, &GPIO_InitStructure_SPI2_SELN); /* Configure SPI MISO */ GPIO_InitStructure_SPI2_MISO.GPIO_Pin = GPIO_Pin_2; GPIO_InitStructure_SPI2_MISO.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure_SPI2_MISO.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure_SPI2_MISO.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure_SPI2_MISO.GPIO_PuPd = GPIO_PuPd_NOPULL; GPIO_Init(GPIOC, &GPIO_InitStructure_SPI2_MISO); /* Configure SPI MOSI */ GPIO_InitStructure_SPI2_MOSI.GPIO_Pin = GPIO_Pin_3; GPIO_InitStructure_SPI2_MOSI.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure_SPI2_MOSI.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure_SPI2_MOSI.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure_SPI2_MOSI.GPIO_PuPd = GPIO_PuPd_NOPULL; GPIO_Init(GPIOC, &GPIO_InitStructure_SPI2_MOSI); /* Configure SPI SCK */ GPIO_InitStructure_SPI2_SCK.GPIO_Pin = GPIO_Pin_10; GPIO_InitStructure_SPI2_SCK.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure_SPI2_SCK.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure_SPI2_SCK.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure_SPI2_SCK.GPIO_PuPd = GPIO_PuPd_NOPULL; GPIO_Init(GPIOB, &GPIO_InitStructure_SPI2_SCK); /* Configure SPI*/ SPI_InitStruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex; SPI_InitStruct.SPI_Mode = SPI_Mode_Master;// ((uint16_t)0x0004) SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b; SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low; SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge; //SPI_CPHA_1Edge SPI_InitStruct.SPI_NSS = SPI_NSS_Soft; SPI_InitStruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_2; //SPI_BaudRatePrescaler_8 //设置波特率预分频值是8 SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB; SPI_InitStruct.SPI_CRCPolynomial = 7; SPI_Init(SPI2,&SPI_InitStruct); SPI_Cmd( SPI2,ENABLE); BSP_SET_SELN; }[/mw_shl_code]

DMA初始化部分：

[mw_shl_code=c,true]void DMA_Configuration(void) { DMA_InitTypeDef DMA_InitStructure; /* Enable DMA clock */ RCC_AHB1PeriphClockCmd(DMA_STREAM_CLOCK, ENABLE); //SPI发送DMA设置 DMA_DeInit(DMA_WR_STREAM); DMA_InitStructure.DMA_Channel = DMA_CHANNEL; DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(SPI2->DR); DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)dma_tx_buf; DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; DMA_InitStructure.DMA_BufferSize = 30400; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Enable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word; DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; DMA_InitStructure.DMA_Priority = DMA_Priority_Medium; DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full; DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; DMA_Init(DMA_WR_STREAM, &DMA_InitStructure); //SPI接收DMA设置 DMA_DeInit(DMA_RX_STREAM); DMA_InitStructure.DMA_Channel = DMA_CHANNEL; DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(SPI2->DR); DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)img_buf; DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory; DMA_InitStructure.DMA_BufferSize = 30400; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Enable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word; DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full; DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; DMA_Init(DMA_RX_STREAM, &DMA_InitStructure); } void SPI2_DMA_Cmd(void) { //使能SPI DMA操作 SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, ENABLE); SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Rx, ENABLE); } void SPI2_DMA_WR_Data( void ) { uint32_t i; //DMA_SetCurrDataCounter(DMA_WR_STREAM, num); //DMA_SetCurrDataCounter(DMA_RX_STREAM, num); DMA_ClearFlag(DMA_WR_STREAM, DMA_FLAG_TCIF4); DMA_ClearFlag(DMA_RX_STREAM, DMA_FLAG_TCIF3); dma_tx_buf[0] = READ_SPI_DATA; for(i = 1; i < 30400; i ++) dma_tx_buf = 0x53; BSP_CLEAR_SELN; //SPI2->DR ; //接送前读一次SPI1->DR，保证接收缓冲区为空 //while((SPI2->SR&1<<1)==0); DMA_Cmd(DMA_WR_STREAM, ENABLE); DMA_Cmd(DMA_RX_STREAM, ENABLE); //while( !DMA_GetFlagStatus(DMA_RX_STREAM, DMA_FLAG_TCIF3)); //DMA_Cmd(DMA_WR_STREAM, DISABLE); //DMA_Cmd(DMA_RX_STREAM, DISABLE); BSP_SET_SELN; }[/mw_shl_code]

然后我采用一下方式不停的发送：

[mw_shl_code=c,true] SPI2_DMA_Cmd(); SPI2_DMA_WR_Data(); while(1) { if(DMA_GetFlagStatus(DMA_WR_STREAM, DMA_FLAG_TCIF4)!=RESET) //判断通道4传输完成 { DMA_ClearFlag(DMA_WR_STREAM, DMA_FLAG_TCIF4);//清除通道4传输完成标志 break; } }[/mw_shl_code]
我现在除了我自己手动拉高和拉低的片选信号，没有其他任何信号出现，这是怎么回事呢