STM32H753 Unable to transmit CAN frames

Ivo · ‎2021-07-21

I'm trying standard CAN communication from a STM32H743 Nucleo board, with an MCP2551 CAN transceiver connected to PA11/PA12. However, I'm not able to transmit anything.

With this same transceiver circuit, I am able to transmit CAN frames when connected to the CAN-FD interface of a NUCLEO-G474RE board, and with the CAN interface of a NUCLEO-F429ZI board.

- After HAL_FDCAN_Start, HAL_FDCAN_GetProtocolStatus returns:

Activity: 0x0

BusOff: 0x0

LastErrorCode: 0x7

ProtocolException: 0x0

TDCvalue: 0x0

- Starting with the second HAL_FDCAN_AddMessageToTxFifoQ() invocation, HAL_ERROR is returned, with HAL_FDCAN_GetProtocolStatus returning

Activity: 0x0

BusOff: 0x1

LastErrorCode: 0x5

ProtocolException: 0x0

TDCvalue: 0x0

- No errors reported by HAL_FDCAN_AddMessageToTxFifoQ() when testing with internal or external loopback mode.

- During all of these, no activity is seen on PA11/PA12 - both pins stay high

It seems like I'm missing a step to enable the CAN interface on PA11/12, but I'm not sure what to try next.

stm32h7xx_hal_map.c:

void HAL_MspInit(void)
{
  __HAL_RCC_SYSCFG_CLK_ENABLE();
}
void HAL_FDCAN_MspInit(FDCAN_HandleTypeDef* hfdcan)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
  if(hfdcan->Instance==FDCAN1)
  {
    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_FDCAN;
    PeriphClkInitStruct.FdcanClockSelection = RCC_FDCANCLKSOURCE_PLL;
    if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
    {
      Error_Handler();
    }
    __HAL_RCC_FDCAN_CLK_ENABLE();
    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**FDCAN1 GPIO Configuration
    PA11     ------> FDCAN1_RX
    PA12     ------> FDCAN1_TX
    */
    GPIO_InitStruct.Pin = GPIO_PIN_11|GPIO_PIN_12;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF9_FDCAN1;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
  }
}

main.c:

FDCAN_HandleTypeDef hfdcan1;
UART_HandleTypeDef huart3;
FDCAN_TxHeaderTypeDef TxHeader;
uint8_t TxData[] = {0x10, 0x32, 0x54, 0x76, 0x98, 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0x00};
:
int main(void)
{
  SCB_EnableICache();
  SCB_EnableDCache();
 
  HAL_Init();
  SystemClock_Config();
 
  MX_GPIO_Init();
  MX_FDCAN1_Init();
  MX_USART3_UART_Init();
 
  HAL_StatusTypeDef rc;
 
  TxHeader.Identifier = 0x111;
  TxHeader.IdType = FDCAN_STANDARD_ID;
  TxHeader.TxFrameType = FDCAN_DATA_FRAME;
  TxHeader.DataLength = FDCAN_DLC_BYTES_8;
  TxHeader.ErrorStateIndicator = FDCAN_ESI_ACTIVE;
  TxHeader.BitRateSwitch = FDCAN_BRS_OFF;
  TxHeader.FDFormat = FDCAN_CLASSIC_CAN;
  TxHeader.TxEventFifoControl = FDCAN_NO_TX_EVENTS;
  TxHeader.MessageMarker = 0;
 
  FDCAN_ClkCalUnitTypeDef ClkCalUnit_FDCAN1;
  ClkCalUnit_FDCAN1.ClockCalibration = FDCAN_CLOCK_CALIBRATION_DISABLE;
  ClkCalUnit_FDCAN1.ClockDivider = FDCAN_CLOCK_DIV10;
  HAL_FDCAN_ConfigClockCalibration(&hfdcan1, &ClkCalUnit_FDCAN1);
 
  HAL_FDCAN_Start(&hfdcan1);
 
  while (1)
  {
      HAL_FDCAN_AddMessageToTxFifoQ(&hfdcan1, &TxHeader, &TxData[0]);
      HAL_Delay(1000);
  }
}
 
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);
  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}
  __HAL_RCC_PLL_PLLSOURCE_CONFIG(RCC_PLLSOURCE_HSE);
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 1;
  RCC_OscInitStruct.PLL.PLLN = 24;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 4;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_3;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 0;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2
                              |RCC_CLOCKTYPE_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV1;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV1;
 
  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}
 
static void MX_FDCAN1_Init(void)
{
  hfdcan1.Instance = FDCAN1;
  hfdcan1.Init.FrameFormat = FDCAN_FRAME_CLASSIC;
  hfdcan1.Init.Mode = FDCAN_MODE_NORMAL;
  hfdcan1.Init.AutoRetransmission = ENABLE;
  hfdcan1.Init.TransmitPause = DISABLE;
  hfdcan1.Init.ProtocolException = ENABLE;
  hfdcan1.Init.NominalPrescaler = 6;
  hfdcan1.Init.NominalSyncJumpWidth = 1;
  hfdcan1.Init.NominalTimeSeg1 = 55;
  hfdcan1.Init.NominalTimeSeg2 = 8;
  hfdcan1.Init.DataPrescaler = 1;
  hfdcan1.Init.DataSyncJumpWidth = 1;
  hfdcan1.Init.DataTimeSeg1 = 1;
  hfdcan1.Init.DataTimeSeg2 = 1;
  hfdcan1.Init.MessageRAMOffset = 0;
  hfdcan1.Init.StdFiltersNbr = 0;
  hfdcan1.Init.ExtFiltersNbr = 0;
  hfdcan1.Init.RxFifo0ElmtsNbr = 0;
  hfdcan1.Init.RxFifo0ElmtSize = FDCAN_DATA_BYTES_8;
  hfdcan1.Init.RxFifo1ElmtsNbr = 0;
  hfdcan1.Init.RxFifo1ElmtSize = FDCAN_DATA_BYTES_8;
  hfdcan1.Init.RxBuffersNbr = 0;
  hfdcan1.Init.RxBufferSize = FDCAN_DATA_BYTES_8;
  hfdcan1.Init.TxEventsNbr = 0;
  hfdcan1.Init.TxBuffersNbr = 0;
  hfdcan1.Init.TxFifoQueueElmtsNbr = 2;
  hfdcan1.Init.TxFifoQueueMode = FDCAN_TX_FIFO_OPERATION;
  hfdcan1.Init.TxElmtSize = FDCAN_DATA_BYTES_8;
  if (HAL_FDCAN_Init(&hfdcan1) != HAL_OK)
  {
    Error_Handler();
  }
}

SKacp.1 · ‎2021-07-21

Hi,

Please see my example for STM32 NUCLEO H743ZI2. Maybe it help You.

Best regards,

Slawek

Ivo · ‎2021-07-22

Thanks Slawek. Unfortunately with your project I'm also getting transmission failures.

I assume it works for you; would you mind telling me which CAN transceiver you're using ?

Best regards,

Ivo.

SKacp.1 · ‎2021-07-22

Hi Ivo,

I used CAN module waveshare with SN65hvd230 transceiver https://www.waveshare.com/sn65hvd230-can-board.htm

Please see this post: https://community.st.com/s/question/0D53W00000ku2u2SAA/hello-i-am-trying-to-communicate-between-2-stm32g4-using-fdcan-using-test-modes-it-works-without-a-problem-when-i-change-to-normal-mode-tx-and-rx-dont-work

Best Regards,

Slawek