SPI获取的数据不符合SCK

时间:2017-11-10 11:46:58

标签: c spi stm32f4discovery hal

我一直在尝试在DMA模式下在STM32F407发现模式上实现spi。我得到了数据,但问题是,我通过脉冲位置调制得到112位数据,数据频率为1MHz。由于这个信息信号是任意的,我已经将我的电路板配置为从机(虽然没有真正的主机),我通过PWM从电路板本身制作SCK。问题是,我正在接收数据,但我在42个脉冲中得到了整个112位。我不确定SCK是如何触发SPI的,因为这种情况不匹配。 有我的SPI配置:

static void MX_SPI1_Init(void)
{
/* SPI1 parameter configuration*/
hspi1.Instance = SPI1;
hspi1.Init.Mode = SPI_MODE_SLAVE;
hspi1.Init.Direction = SPI_DIRECTION_2LINES;
hspi1.Init.DataSize = SPI_DATASIZE_8BIT;
hspi1.Init.CLKPolarity = SPI_POLARITY_HIGH;
hspi1.Init.CLKPhase = SPI_PHASE_1EDGE;
hspi1.Init.NSS = SPI_NSS_HARD_INPUT;
hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi1.Init.BaudRatePrescaler=SPI_BAUDRATEPRESCALER_4;
hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspi1.Init.CRCPolynomial = 7;
if (HAL_SPI_Init(&hspi1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}}

我的msp.c文件

void HAL_SPI_MspInit(SPI_HandleTypeDef* hspi)
{
GPIO_InitTypeDef GPIO_InitStruct;
if(hspi->Instance==SPI1)
{
/* USER CODE BEGIN SPI1_MspInit 0 */
    __HAL_RCC_GPIOA_CLK_ENABLE();
    __HAL_RCC_GPIOB_CLK_ENABLE();
/* USER CODE END SPI1_MspInit 0 */
/* Peripheral clock enable */
__HAL_RCC_SPI1_CLK_ENABLE();

/**SPI1 GPIO Configuration    
PA4     ------> SPI1_NSS
PA6     ------> SPI1_MISO
PA7     ------> SPI1_MOSI
PB3     ------> SPI1_SCK 
*/
GPIO_InitStruct.Pin = GPIO_PIN_4|GPIO_PIN_6|GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF5_SPI1;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

GPIO_InitStruct.Pin = GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF5_SPI1;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

/* SPI1 DMA Init */
/* SPI1_RX Init */
hdma_spi1_rx.Instance = DMA2_Stream0;
hdma_spi1_rx.Init.Channel = DMA_CHANNEL_3;
hdma_spi1_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;
hdma_spi1_rx.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_spi1_rx.Init.MemInc = DMA_MINC_ENABLE;
hdma_spi1_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
hdma_spi1_rx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
hdma_spi1_rx.Init.Mode = DMA_NORMAL;
hdma_spi1_rx.Init.Priority = DMA_PRIORITY_LOW;
hdma_spi1_rx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
if (HAL_DMA_Init(&hdma_spi1_rx) != HAL_OK)
{
  _Error_Handler(__FILE__, __LINE__);
}

__HAL_LINKDMA(hspi,hdmarx,hdma_spi1_rx);

/* SPI1 interrupt Init */
HAL_NVIC_SetPriority(SPI1_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(SPI1_IRQn);
/* USER CODE BEGIN SPI1_MspInit 1 */
/* USER CODE END SPI1_MspInit 1 */
}}

我通过以下方式启动SPI:

HAL_SPI_Receive_DMA(&hspi1, data, 14); //data is array uint8_t
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_RESET); //NSS out which is shortened with real NSS of Slave
HAL_TIM_PWM_Start(&htim3, TIM_CHANNEL_1); /clock

获得数据后,我在SPI处理程序中使用它:

HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_SET);
HAL_TIM_PWM_Stop(&htim3, TIM_CHANNEL_1);

在内存中我得到了所有的112(14个字节)     Data

还有振动图     Oscilogram

有什么想法吗? 我使用CubeMX作为我的代码的基础

0 个答案:

没有答案