scfor123456 发表于 2019-8-27 18:46
这个到底是怎么回事？

楼主那个SPI每次发送1个字节的无符号整数，如何发送有符号的数呢？

wenyangzeng 发表于 2019-8-27 19:09
楼主那个SPI每次发送1个字节的无符号整数，如何发送有符号的数呢？

我发的是16位数据

做过一次SPI从设备。当时是配置从设备使用NSS，和DMA。两者都要使用，才能正常工作。

uwyciw100 发表于 2019-8-28 11:27
做过一次SPI从设备。当时是配置从设备使用NSS，和DMA。两者都要使用，才能正常工作。 ...

#define FUNCTION_TO_MOTOR_NUM_MAX 10
#define MOTOR_TO_FUNCTION_NUM_MAX 10

uint8_t gSendToMotorDataBuff1[FUNCTION_TO_MOTOR_NUM_MAX];
uint8_t gSendToFunctionDataBuff1[MOTOR_TO_FUNCTION_NUM_MAX]={0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff};

/**
  * @brief  GPIO的初始化配置函数
  * @param  无
  * @retval 无
  */
void spi2_Init(void)
{
        spi2_dma1_init();
       
   /* Enable the peripheral clock SPI2 */
  RCC->APB1ENR |= RCC_APB1ENR_SPI2EN;

  /* Configure SPI2 in slave */
  /* nSS hard, slave, CPOL and CPHA at zero (rising first edge) */
  /* (1) TX and RX with DMA, RXNE IT, 8-bit Rx fifo */
  /* (2) Enable SPI2 */
  SPI2->CR2 = SPI_CR2_TXDMAEN | SPI_CR2_RXDMAEN | SPI_CR2_RXNEIE | SPI_CR2_FRXTH | SPI_CR2_DS_2 | SPI_CR2_DS_1 | SPI_CR2_DS_0|SPI_CR2_FRF; /* (1) */
  SPI2->CR1 |= SPI_CR1_SPE; /* (2) */       
               
}

void spi2_dma1_init(void)
{
  /* Enable the peripheral clock DMA11 */
  RCC->AHBENR |= RCC_AHBENR_DMA1EN;
  
  /* DMA1 Channel4 SPI2_RX config */
  /* (1) Peripheral address */
  /* (2) Memory address */
  /* (3) Data size */
  /* (4) Memory increment */
  /*     Peripheral to memory */
  /*     8-bit transfer */
  /*     Transfer complete IT */
  DMA1_Channel4->CPAR = (uint32_t)&(SPI2->DR); /* (1) */
  DMA1_Channel4->CMAR = (uint32_t)gSendToMotorDataBuff1; /* (2) */
  DMA1_Channel4->CNDTR = FUNCTION_TO_MOTOR_NUM_MAX; /* (3) */
  DMA1_Channel4->CCR |= DMA_CCR_MINC | DMA_CCR_TCIE  | DMA_CCR_EN; /* (4) */
  
  /* DMA1 Channel5 SPI2_TX config */
  /* (5) Peripheral address */
  /* (6) Memory address */
  /* (7) Memory increment */
  /*     Memory to peripheral*/
  /*     8-bit transfer */
  DMA1_Channel5->CPAR = (uint32_t)&(SPI2->DR); /* (5) */
  DMA1_Channel5->CMAR = (uint32_t)gSendToFunctionDataBuff1; /* (6) */
  DMA1_Channel5->CCR |= DMA_CCR_MINC | DMA_CCR_DIR; /* (7) */
  DMA1_Channel5->CNDTR = MOTOR_TO_FUNCTION_NUM_MAX; /* Data size */
  DMA1_Channel5->CCR |= DMA_CCR_EN;       
       
  /* Configure IT */
  /* (8) Set priority for DMA1_Channel4_IRQn */
  /* (9) Enable DMA1_Channel4_IRQn */
  NVIC_SetPriority(DMA1_Channel4_IRQn, 0); /* (8) */
  NVIC_EnableIRQ(DMA1_Channel4_IRQn); /* (9) */
       
}

/**
  * @brief  This function handles DMA1 channel 4 TC interrupt request.
  * @param  None
  * @retval None
  */
void DMA1_Channel4_IRQHandler(void)
{
  if((DMA1->ISR & DMA_ISR_TCIF4) == DMA_ISR_TCIF4)
  {
    DMA1->IFCR |= DMA_IFCR_CTCIF4; /* Clear TC flag */
   
    DMA1_Channel4->CCR &=~ DMA_CCR_EN;
        DMA1_Channel4->CMAR = (uint32_t)gSendToMotorDataBuff1; /* (2) */
    DMA1_Channel4->CNDTR = FUNCTION_TO_MOTOR_NUM_MAX; /* Data size */
    DMA1_Channel4->CCR |= DMA_CCR_EN;
               
        spi2_send_data();
  }
}



void spi2_send_data(void)
{
        uint8_t i;
        gSendToFunctionDataBuff1[0]=gSendToMotorDataBuff1[0];
        for(i=1;i<MOTOR_TO_FUNCTION_NUM_MAX;i++)
        {
                gSendToFunctionDataBuff1=gSendToMotorDataBuff1;
        }
  /* start 16-bit transmission with DMA*/
  /* Prepare Slave */
  DMA1_Channel5->CCR &=~ DMA_CCR_EN;
  DMA1_Channel5->CMAR = (uint32_t)gSendToFunctionDataBuff1; /* (6) */
  DMA1_Channel5->CNDTR = MOTOR_TO_FUNCTION_NUM_MAX; /* Data size */
  DMA1_Channel5->CCR |= DMA_CCR_EN;       

}
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
请帮我看看从机的处理，DMA接收中断中更新下次需发送的数据，主机是定时发送10个数据，从机接收后元数据返回给主机。