How can fix CAN Receive problem in Normal Mode

[Suat Berkant Gulen]

Posted on October 02, 2017 at 20:28

Hi,

I try to communicate via CAN. I can transmit data to PCAN but i can't receive in Normal Mode. When i use Loopback, i can receive data. Please Help me.. My configuration is here

/* CAN1 init function */

static void MX_CAN1_Init(void){

CAN_FilterConfTypeDef sFilterConfig;

static CanTxMsgTypeDef TxMessage; static CanRxMsgTypeDef RxMessage;

/*♯♯-1- Configure the CAN peripheral ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

hcan1.Instance = CANx; hcan1.pTxMsg = &TxMessage; hcan1.pRxMsg = &RxMessage;

hcan1.Init.TTCM = DISABLE;

hcan1.Init.ABOM = DISABLE; hcan1.Init.AWUM = DISABLE; hcan1.Init.NART = DISABLE; hcan1.Init.RFLM = DISABLE; hcan1.Init.TXFP = DISABLE; hcan1.Init.Mode = CAN_MODE_NORMAL; hcan1.Init.SJW = CAN_SJW_1TQ; hcan1.Init.BS1 = CAN_BS1_6TQ; hcan1.Init.BS2 = CAN_BS2_7TQ; hcan1.Init.Prescaler = 4;

if (HAL_CAN_Init(&hcan1) != HAL_OK)

{ /* Initialization Error */ Error_Handler(); }

/*♯♯-2- Configure the CAN Filter ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

sFilterConfig.FilterNumber = 0; sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK; sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT; sFilterConfig.FilterIdHigh = 0x0000; sFilterConfig.FilterIdLow = 0x0000; sFilterConfig.FilterMaskIdHigh = 0x0000; sFilterConfig.FilterMaskIdLow = 0x0000; sFilterConfig.FilterFIFOAssignment = CAN_FIFO0; sFilterConfig.FilterActivation = ENABLE; sFilterConfig.BankNumber = 0;

if (HAL_CAN_ConfigFilter(&hcan1, &sFilterConfig) != HAL_OK)

{ /* Filter configuration Error */ Error_Handler(); }

/*♯♯-3- Configure Transmission process ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

hcan1.pTxMsg->StdId = 0x321; hcan1.pTxMsg->ExtId = 0x01; hcan1.pTxMsg->RTR = CAN_RTR_DATA; hcan1.pTxMsg->IDE = CAN_ID_STD; hcan1.pTxMsg->DLC = 2;

}

And i use these functions to enable them:

if (HAL_CAN_Receive_IT(&hcan1, CAN_FIFO0) != HAL_OK)

{ /* Reception Error */ Error_Handler(); }

//////////////////////////////////////////////////////////////////////////////////////////////////

if (HAL_CAN_Transmit(&hcan1, 10) != HAL_OK)

{ /* Transmission Error */ Error_Handler(); }

My MspDeInit functions :

void HAL_CAN_MspInit(CAN_HandleTypeDef *hcan)

{    GPIO_InitTypeDef GPIO_InitStruct;

   *♯♯-1- Enable peripherals and GPIO Clocks ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

   /* CAN1 Periph clock enable */    CANx_CLK_ENABLE();    /   * Enable GPIO clock ****************************************/    CANx_GPIO_CLK_ENABLE();

   /*♯♯-2- Configure peripheral GPIO ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

   /* CAN1 TX GPIO pin configuration */    GPIO_InitStruct.Pin = CANx_TX_PIN;    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;    GPIO_InitStruct.Pull = GPIO_PULLUP;    GPIO_InitStruct.Alternate = CANx_TX_AF;

   HAL_GPIO_Init(CANx_TX_GPIO_PORT, &GPIO_InitStruct);

   /* CAN1 RX GPIO pin configuration */

   GPIO_InitStruct.Pin = CANx_RX_PIN;    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;    GPIO_InitStruct.Pull = GPIO_PULLUP;    GPIO_InitStruct.Alternate = CANx_RX_AF;

   HAL_GPIO_Init(CANx_RX_GPIO_PORT, &GPIO_InitStruct);

   /*♯♯-3- Configure the NVIC ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

   /* NVIC configuration for CAN1 Reception complete interrupt */    HAL_NVIC_SetPriority(CANx_RX_IRQn, 2, 0);    HAL_NVIC_EnableIRQ(CANx_RX_IRQn);}void HAL_CAN_MspDeInit(CAN_HandleTypeDef *hcan){    /*♯♯-1- Reset peripherals ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/    CANx_FORCE_RESET();    CANx_RELEASE_RESET();

   /*♯♯-2- Disable peripherals and GPIO Clocks ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

   /* De-initialize the CAN1 TX GPIO pin */    HAL_GPIO_DeInit(CANx_TX_GPIO_PORT, CANx_TX_PIN);    /* De-initialize the CAN1 RX GPIO pin */    HAL_GPIO_DeInit(CANx_RX_GPIO_PORT, CANx_RX_PIN);

   /*♯♯-4- Disable the NVIC for CAN reception ♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯♯*/

   HAL_NVIC_DisableIRQ(CANx_RX_IRQn);}#stm32f7

[fabio frasi]

Posted on October 05, 2017 at 14:03

If using interrupt must to use interrupt sender

// MUST USE THIS LINE OF CODE

while(CAN_busy_check(&hcan1) == 1)HAL_Delay(1);      

hcan1.pTxMsg->StdId = 12345;

hcan1.pTxMsg->DLC = 2;hcan1.pTxMsg->Data[0]=1;

hcan1.pTxMsg->Data[0]=2;

if(HAL_CAN_Transmit_IT(&hcan1) != HAL_OK)

[fabio frasi]

Posted on October 05, 2017 at 14:06

Can init for you 500kbit

static void MX_CAN1_Init(void)

{  hcan1.pTxMsg = &TxMessage1;  hcan1.pRxMsg = &RxMessage1;      hcan1.Instance = CAN1;  hcan1.Init.Prescaler = 5;  hcan1.Init.Mode = CAN_MODE_NORMAL;  hcan1.Init.SJW = CAN_SJW_1TQ;  hcan1.Init.BS1 = CAN_BS1_12TQ;  hcan1.Init.BS2 = CAN_BS2_5TQ;  hcan1.Init.TTCM = DISABLE;  hcan1.Init.ABOM = DISABLE;  hcan1.Init.AWUM = DISABLE;  hcan1.Init.NART = DISABLE;  hcan1.Init.RFLM = DISABLE;  hcan1.Init.TXFP = DISABLE;      if (HAL_CAN_Init(&hcan1) != HAL_OK)  {    Error_Handler();  }      sFilterConfig1.FilterNumber = 1;  sFilterConfig1.FilterMode = CAN_FILTERMODE_IDMASK;  sFilterConfig1.FilterScale = CAN_FILTERSCALE_32BIT;  sFilterConfig1.FilterIdHigh = 0x0000;  sFilterConfig1.FilterIdLow = 0x0000;  sFilterConfig1.FilterMaskIdHigh = 0x0000;  sFilterConfig1.FilterMaskIdLow = 0x0000;  sFilterConfig1.FilterFIFOAssignment = 0;  sFilterConfig1.FilterActivation = ENABLE;  sFilterConfig1.BankNumber = 14;  if(HAL_CAN_ConfigFilter(&hcan1, &sFilterConfig1) != HAL_OK)while(1);

if(HAL_CAN_Receive_IT(&hcan1, CAN_FIFO0) != HAL_OK) while(1);

            hcan1.pTxMsg->StdId = 0x00;    hcan1.pTxMsg->ExtId = 0x00;    hcan1.pTxMsg->RTR = CAN_RTR_DATA;    hcan1.pTxMsg->IDE = CAN_ID_STD;    hcan1.pTxMsg->DLC = 8;

}

[Tesla DeLorean]

Posted on October 05, 2017 at 16:51

Probably NOT 500k in this case.

[Tesla DeLorean]

Posted on October 05, 2017 at 16:52

Your settings are almost certainly NOT 1Mbit/s

What is the APB clock for the CAN peripheral?

[T J]

Posted on October 06, 2017 at 01:19

You wont be able to receive anything if ABOM is not set.

to enable automatic bus-off management, set the hcan1.Init.ABOM= ENABLE

to be sure, you should disable the filters too:   sFilterConfig1.FilterActivation = DISABLE

to check the final baud rate, transmit something and check the Scope.

I used CubeMx to calculate the baud settings.

I used CanDo hardware to transmit every 10mSec, then I made the receiver work first.

[Tesla DeLorean]

Posted on October 06, 2017 at 01:35

>>I used CanDo hardware to transmit every 10mSec, then I made the receiver work first.

Very good advice

>>I used CubeMx to calculate the baud settings.

It's not complicated, and easier than scoping

CAN Rate = ((APBClock / Prescaler) / (x + y + z))   where the sum is of the bit quanta widths

[T J]

Posted on October 06, 2017 at 01:39

its so nice to see the scope running.

You can see if the data is clean, you can check the leading edges, its well recommended.

a 4 channel Color Scope like TDS2024 is a minimum level of scope for a professional engineer.