[嵌入式]STM32F4 读取ADC128S022

因为有项目需求，需要用到模拟量采集，但是又考虑到抗干扰，故采用专用ADC芯片，用ADUM1411将控制电路和采集电路隔离，并且考虑到IIC的方案采用软件模拟比较占用系统资源，因此确定方案，采用带有SPI功能的ADC128S022;采用DMA的模式自动采集8路adc信号。

硬件方案

100欧姆电阻必须要有

?软件方案

读1路adc数据，只需要发送两个字节?

第一个字节只需要改变第3-第5位的值，确定要采样的通道，其他都可以填0；

第二个字节直接填0就好了；

在接收的数据中只取后12位就可以了；

?实测读取adc通道时，会滞后，比如读0通道，实际读到的通道7；

#ifdef SPIU16
uint16_t aTxBuffer[8] = {0X0000,0X0800,0X1000,0X1800,0X2000,0X2800,0X3000,0X3800};//发送数组
uint16_t aRxBuffer[8];//接收数组
#else
uint8_t aTxBuffer[16] = {0X00,0x00,0X08,0x00,0X10,0x00,0X18,0x00,0X20,0x00,0X28,0x00,0X30,0x00,0X38,0x00};//发送数组
uint8_t aRxBuffer[16];//接收数组
#endif
  GPIO_InitTypeDef  GPIO_InitStructure;
  SPI_InitTypeDef   SPI_InitStructure;
  DMA_InitTypeDef 	DMA_InitStructure;
	NVIC_InitTypeDef  NVIC_InitStructure;
  RCC_AHB1PeriphClockCmd(SPIx_SCK_GPIO_CLK | SPIx_MISO_GPIO_CLK | SPIx_MOSI_GPIO_CLK, ENABLE);//使能SPI时钟
	RCC_AHB1PeriphClockCmd(SPIx_CS_GPIO_CLK, ENABLE);//使能片选时钟
#ifdef	SPI_3
  RCC_APB1PeriphClockCmd(SPIx_CLK, ENABLE);//使能SPI3时钟	
#else
	 RCC_APB2PeriphClockCmd(SPIx_CLK, ENABLE);//使能SPI4时钟
#endif
	RCC_AHB1PeriphClockCmd(SPIx_DMA_CLK, ENABLE); //开启DMA
	
  //SPI外设初始化
  GPIO_InitStructure.GPIO_Pin = SPIx_SCK_PIN;// SCK配置
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//上拉
  GPIO_Init(SPIx_SCK_GPIO_PORT, &GPIO_InitStructure);//初始化	

  GPIO_InitStructure.GPIO_Pin = SPIx_MISO_PIN;//MISO配置
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//上拉
  GPIO_Init(SPIx_MISO_GPIO_PORT, &GPIO_InitStructure);//初始化	
	
	GPIO_InitStructure.GPIO_Pin = SPIx_MOSI_PIN;//MOSI配置
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//上拉
  GPIO_Init(SPIx_MOSI_GPIO_PORT, &GPIO_InitStructure);//初始化	
	
	GPIO_InitStructure.GPIO_Pin = SPIx_CS_PIN;//片选配置
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;//输出功能
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//上拉
  GPIO_Init(SPIx_CS_GPIO_PORT, &GPIO_InitStructure);//初始化
	CS_HIGH;  //片选拉高
	GPIO_PinAFConfig(SPIx_SCK_GPIO_PORT,SPIx_SCK_SOURCE,SPIx_SCK_AF); //SCK复用
	GPIO_PinAFConfig(SPIx_MISO_GPIO_PORT,SPIx_MISO_SOURCE,SPIx_MISO_AF); //MISO复用
	GPIO_PinAFConfig(SPIx_MOSI_GPIO_PORT,SPIx_MOSI_SOURCE,SPIx_MOSI_AF); //MOSI复用

#ifdef SPIU16
	#ifdef	SPI_3
	RCC_APB1PeriphResetCmd(SPIx_CLK,ENABLE);//复位SPI3
	RCC_APB1PeriphResetCmd(SPIx_CLK,DISABLE);//停止复位SPI3
	#else
	RCC_APB2PeriphResetCmd(SPIx_CLK,ENABLE);//复位SPI4
	RCC_APB2PeriphResetCmd(SPIx_CLK,DISABLE);//停止复位SPI4
	#endif
	SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;  //设置SPI单向或者双向的数据模式:SPI设置为双线双向全双工
	SPI_InitStructure.SPI_Mode = SPI_Mode_Master;		//设置SPI工作模式:设置为主SPI
	SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;		//设置SPI的数据大小:SPI发送接收16位帧结构
	SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;		//串行同步时钟的空闲状态为高电平
	SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;	//串行同步时钟的第一个跳变沿（上升或下降）数据被采样-----------
	SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;		//NSS信号由硬件（NSS管脚）还是软件（使用SSI位）管理:内部NSS信号有SSI位控制	
	SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_128;		//定义波特率预分频的值:波特率预分频值为64
	SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;	//指定数据传输从MSB位还是LSB位开始:数据传输从MSB位开始
	SPI_InitStructure.SPI_CRCPolynomial = 0;	//CRC值计算的多项式
	SPI_Init(SPIx, &SPI_InitStructure);  //根据SPI_InitStruct中指定的参数初始化外设SPIx寄存器  
	SPI_Cmd(SPIx, ENABLE); //使能SPI外设

  DMA_DeInit(SPIx_TX_DMA_STREAM);
  DMA_DeInit(SPIx_RX_DMA_STREAM);
	while (DMA_GetCmdStatus(SPIx_TX_DMA_STREAM) != DISABLE) 
	{		
	}
	while (DMA_GetCmdStatus(SPIx_RX_DMA_STREAM) != DISABLE) 
	{		
	}
  /* Configure DMA Initialization Structure */
  DMA_InitStructure.DMA_BufferSize = BUFFERSIZE ; //数据传输量
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable ;//
  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull ;//
  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single ;//
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;//存储器数据长度
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //存储器增量模式
  DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;//普通模式
  DMA_InitStructure.DMA_PeripheralBaseAddr =(uint32_t) (&(SPIx->DR)) ;//外设地址
  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//外设突发单次传输
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;//外设数据长度
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设非增量模式
  DMA_InitStructure.DMA_Priority = DMA_Priority_High;//
  /* Configure TX DMA */
  DMA_InitStructure.DMA_Channel = SPIx_TX_DMA_CHANNEL ;//
  DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral ;//
  DMA_InitStructure.DMA_Memory0BaseAddr =(uint32_t)aTxBuffer ;//
  DMA_Init(SPIx_TX_DMA_STREAM, &DMA_InitStructure);//
  /* Configure RX DMA */
  DMA_InitStructure.DMA_Channel = SPIx_RX_DMA_CHANNEL ;//
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;//
  DMA_InitStructure.DMA_Memory0BaseAddr =(uint32_t)aRxBuffer ; //
  DMA_Init(SPIx_RX_DMA_STREAM, &DMA_InitStructure);	
	//DMA_ITConfig(SPIx_TX_DMA_STREAM, DMA_IT_TC, ENABLE);
	DMA_ITConfig(SPIx_RX_DMA_STREAM, DMA_IT_TC, ENABLE);
	SPI_Init(SPIx, &SPI_InitStructure);
	NVIC_InitStructure.NVIC_IRQChannel = SPIx_RX_DMA_IRQ; //接收完成
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 4;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);  
	DMA_ClearFlag(SPIx_TX_DMA_STREAM,SPIx_TX_DMA_FLAG_TCIF);
	DMA_ClearFlag(SPIx_RX_DMA_STREAM,SPIx_RX_DMA_FLAG_TCIF); 	
	CS_LOW;	
	DMA_Cmd(SPIx_TX_DMA_STREAM,ENABLE);
  DMA_Cmd(SPIx_RX_DMA_STREAM,ENABLE);
  SPI_I2S_DMACmd(SPIx, SPI_I2S_DMAReq_Tx, ENABLE);
	SPI_I2S_DMACmd(SPIx, SPI_I2S_DMAReq_Rx, ENABLE);	

#else
	RCC_APB1PeriphResetCmd(RCC_APB1Periph_SPI3,ENABLE);//复位SPI3
	RCC_APB1PeriphResetCmd(RCC_APB1Periph_SPI3,DISABLE);//停止复位SPI3
	SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;  //设置SPI单向或者双向的数据模式:SPI设置为双线双向全双工
	SPI_InitStructure.SPI_Mode = SPI_Mode_Master;		//设置SPI工作模式:设置为主SPI
	SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;		//设置SPI的数据大小:SPI发送接收16位帧结构
	SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;		//串行同步时钟的空闲状态为高电平
	SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;	//串行同步时钟的第一个跳变沿（上升或下降）数据被采样-----------
	SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;		//NSS信号由硬件（NSS管脚）还是软件（使用SSI位）管理:内部NSS信号有SSI位控制
	SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_256;		//定义波特率预分频的值:波特率预分频值为64
	SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;	//指定数据传输从MSB位还是LSB位开始:数据传输从MSB位开始
	SPI_InitStructure.SPI_CRCPolynomial = 7;	//CRC值计算的多项式
	SPI_Init(SPI3, &SPI_InitStructure);  //根据SPI_InitStruct中指定的参数初始化外设SPIx寄存器  
	SPI_Cmd(SPI3, ENABLE); //使能SPI外设

  DMA_DeInit(SPIx_TX_DMA_STREAM);
  DMA_DeInit(SPIx_RX_DMA_STREAM);

  /* Configure DMA Initialization Structure */
  DMA_InitStructure.DMA_BufferSize = BUFFERSIZE ; //数据传输量
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable ;//
  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull ;//
  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single ;//
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;//存储器数据长度
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //存储器增量模式
  DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;//普通模式
  DMA_InitStructure.DMA_PeripheralBaseAddr =(uint32_t) (&(SPIx->DR)) ;//外设地址
  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//外设突发单次传输
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;//外设数据长度
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设非增量模式
  DMA_InitStructure.DMA_Priority = DMA_Priority_High;//
  /* Configure TX DMA */
  DMA_InitStructure.DMA_Channel = SPIx_TX_DMA_CHANNEL ;//
  DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral ;//
  DMA_InitStructure.DMA_Memory0BaseAddr =(uint32_t)aTxBuffer ;//
  DMA_Init(SPIx_TX_DMA_STREAM, &DMA_InitStructure);//
  /* Configure RX DMA */
  DMA_InitStructure.DMA_Channel = SPIx_RX_DMA_CHANNEL ;//
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;//
  DMA_InitStructure.DMA_Memory0BaseAddr =(uint32_t)aRxBuffer ; //
  DMA_Init(SPIx_RX_DMA_STREAM, &DMA_InitStructure);
	
	//DMA_ITConfig(SPIx_TX_DMA_STREAM, DMA_IT_TC, ENABLE);
	DMA_ITConfig(SPIx_RX_DMA_STREAM, DMA_IT_TC, ENABLE);
	SPI_Init(SPIx, &SPI_InitStructure);

	NVIC_InitStructure.NVIC_IRQChannel = SPIx_RX_DMA_IRQ;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure); 	
 	
	CS_LOW;	
	DMA_Cmd(SPIx_TX_DMA_STREAM,ENABLE);
  DMA_Cmd(SPIx_RX_DMA_STREAM,ENABLE);
  SPI_I2S_DMACmd(SPIx, SPI_I2S_DMAReq_Tx, ENABLE);
	SPI_I2S_DMACmd(SPIx, SPI_I2S_DMAReq_Rx, ENABLE);	
#endif
}
//------------------------------------------------------------------------------------------------------
// 功能描述  ：DMA数据接收完成中断
// 输入  ：无
// 输出  : 无
// 调用  ：中断调用
//------------------------------------------------------------------------------------------------------

void DMA1_Stream0_IRQHandler(void)  //SPI3 DMA接收中断
{         
	if((DMA_GetFlagStatus(SPIx_RX_DMA_STREAM,SPIx_RX_DMA_FLAG_TCIF)==SET) && (DMA_GetFlagStatus(SPIx_TX_DMA_STREAM,SPIx_TX_DMA_FLAG_TCIF)==SET))	
	{  
		DMA_ClearFlag(SPIx_TX_DMA_STREAM,SPIx_TX_DMA_FLAG_TCIF);
		DMA_ClearFlag(SPIx_RX_DMA_STREAM,SPIx_RX_DMA_FLAG_TCIF);
		CS_HIGH;
		
		SPIx_TX_DMA_STREAM->CR &= ~(uint32_t)DMA_SxCR_EN; //DMA发送禁止
		SPIx_RX_DMA_STREAM->CR &= ~(uint32_t)DMA_SxCR_EN;//DMA接收禁止

		SPIx->CR2 &= (uint16_t)~SPI_I2S_DMAReq_Tx;    //SPI DMA发送禁止
		SPIx->CR2 &= (uint16_t)~SPI_I2S_DMAReq_Rx;    //SPI DMA接收禁止

		CS_LOW;

		SPIx_TX_DMA_STREAM->CR |= (uint32_t)DMA_SxCR_EN;//DMA发送使能

		SPIx_RX_DMA_STREAM->CR |= (uint32_t)DMA_SxCR_EN;//DMA发送使能

		SPIx->CR2 |= SPI_I2S_DMAReq_Tx;//SPI DMA发送使能

		SPIx->CR2 |= SPI_I2S_DMAReq_Rx;//SPI DMA发送使能
	}    

}