STM32F7 SPI send/receive issue

[MSavc]

Hi!

I have an issue with SPI communication on STM32F746 MCU.

I have two MCU connected via SPI on my board in 16 bit mode, both MCU`s are STM32F746. At start point it seems normal, but after some time it starts to drop packeges cause CRC32 check(CRC32 computes on CRC module by hardware) not solved.

When i debugging dropped packets, i`ve see a repetition of pervious byte in next cell of receive buffer(for debugging, all cellc in buffer are initialize with unique value).

It not deterministically, so most part of packets are normal, but i wanna solve this "bug".

Can somebody help me?

[David Littell]

What do your SPI_HandleTypeDef and DMA_HandleTypeDef structure initializations look like?

[MSavc]

Here they are

void MX_SPI2_Init(void)
{
 
  hspi2.Instance = SPI2;
  hspi2.Init.Mode = SPI_MODE_MASTER;
  hspi2.Init.Direction = SPI_DIRECTION_2LINES;
  hspi2.Init.DataSize = SPI_DATASIZE_16BIT;
  hspi2.Init.CLKPolarity = SPI_POLARITY_HIGH;
  hspi2.Init.CLKPhase = SPI_PHASE_2EDGE;
  hspi2.Init.NSS = SPI_NSS_HARD_OUTPUT;
  hspi2.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_4;
  hspi2.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi2.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi2.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi2.Init.CRCPolynomial = 7;
  hspi2.Init.CRCLength = SPI_CRC_LENGTH_DATASIZE;
  hspi2.Init.NSSPMode = SPI_NSS_PULSE_DISABLE;
  if (HAL_SPI_Init(&hspi2) != HAL_OK)
  {
    Error_Handler();
  }
 
}
 
 /* Peripheral DMA init*/
  
    hdma_spi2_rx.Instance = DMA1_Stream3;
    hdma_spi2_rx.Init.Channel = DMA_CHANNEL_0;
    hdma_spi2_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;
    hdma_spi2_rx.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_spi2_rx.Init.MemInc = DMA_MINC_ENABLE;
    hdma_spi2_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
    hdma_spi2_rx.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
    hdma_spi2_rx.Init.Mode = DMA_NORMAL;
    hdma_spi2_rx.Init.Priority = DMA_PRIORITY_LOW;
    hdma_spi2_rx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
    if (HAL_DMA_Init(&hdma_spi2_rx) != HAL_OK)
    {
      Error_Handler();
    }
 
    __HAL_LINKDMA(spiHandle,hdmarx,hdma_spi2_rx);
 
    hdma_spi2_tx.Instance = DMA1_Stream4;
    hdma_spi2_tx.Init.Channel = DMA_CHANNEL_0;
    hdma_spi2_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;
    hdma_spi2_tx.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_spi2_tx.Init.MemInc = DMA_MINC_ENABLE;
    hdma_spi2_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
    hdma_spi2_tx.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
    hdma_spi2_tx.Init.Mode = DMA_NORMAL;
    hdma_spi2_tx.Init.Priority = DMA_PRIORITY_LOW;
    hdma_spi2_tx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
    if (HAL_DMA_Init(&hdma_spi2_tx) != HAL_OK)
    {
      Error_Handler();
    }
 
    __HAL_LINKDMA(spiHandle,hdmatx,hdma_spi2_tx);
 
    /* Peripheral interrupt init */
    HAL_NVIC_SetPriority(SPI2_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(SPI2_IRQn);

[David Littell]

Hm. The only significant differences I see between us are CLKPhase, NSS (I always control NSS via software), and the DMA FIFO (not all the active SPI's have the FIFO enabled).

One thing I do is read the SPI receive fifo twice (to ensure it's empty) before the HAL call. You could try that.