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STM32F4X CPU halts after CAN Bus connector unplug

Question asked by Mohajer on Aug 9, 2015
Latest reply on Aug 9, 2015 by Mohajer

Hi,

I am using CAN bus on STM32F407 using standard peripheral library.

When I unplug CAN bus connector, the CPU halts. After reconnecting CAN bus connector, the CPU is still freezing and needs hardware restart.

I want to microcontroller continues running after the bus disconnected.

 

I have used debugger and I see the CPU stuck in assert line:

 

uint8_t CAN_TransmitStatus(CAN_TypeDef* CANx, uint8_t TransmitMailbox)

{

  uint32_t state = 0;

 

  /* Check the parameters */

  assert_param(IS_CAN_ALL_PERIPH(CANx));

  assert_param(IS_CAN_TRANSMITMAILBOX(TransmitMailbox)); sticks here!!!!

 

// ===================================================

 

CAN_InitTypeDef        CAN_InitStructure;
CAN_FilterInitTypeDef  CAN_FilterInitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
 
CanTxMsg TxMessage;
volatile uint8_t StatusCAN = 0;
 
volatile uint16_t CanBusTxFailureCounter = 0x0000;
volatile uint16_t CanBusTxFailureCounterMax = 0xFFFF;

 

 

void CAN_Config(void)
{
  GPIO_InitTypeDef  GPIO_InitStructure;
  
  /* CAN GPIOs configuration **************************************************/
 
  /* Enable GPIO clock */
  RCC_AHB1PeriphClockCmd(CAN_GPIO_CLK, ENABLE);
 
  /* Connect CAN pins to AF9 */
  GPIO_PinAFConfig(CAN_GPIO_PORT, CAN_RX_SOURCE, CAN_AF_PORT);
  GPIO_PinAFConfig(CAN_GPIO_PORT, CAN_TX_SOURCE, CAN_AF_PORT); 
  
  /* Configure CAN RX and TX pins */
  GPIO_InitStructure.GPIO_Pin = CAN_RX_PIN | CAN_TX_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
  GPIO_Init(CAN_GPIO_PORT, &GPIO_InitStructure);
 
  /* CAN configuration ********************************************************/  
  /* Enable CAN clock */
  RCC_APB1PeriphClockCmd(CAN_CLK, ENABLE);
  
  /* CAN register init */
  CAN_DeInit(CANx);
 
  /* CAN cell init */
  CAN_InitStructure.CAN_TTCM = DISABLE;
  CAN_InitStructure.CAN_ABOM = DISABLE;
  CAN_InitStructure.CAN_AWUM = DISABLE;
  CAN_InitStructure.CAN_NART = DISABLE;
  CAN_InitStructure.CAN_RFLM = DISABLE;
  CAN_InitStructure.CAN_TXFP = DISABLE;
  CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;
  CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;
    
  /* CAN Baudrate = 500 Kbit/s (CAN clocked at 42 MHz) */ 
    // CAN_BitRate = CAN_CLK / (CAN_Prescaler * (CAN_SJW + CAN_BS1 + CAN_BS2)) - 500Kbit/s = 42MHz/(4 * (1 + 12 + 8))
  CAN_InitStructure.CAN_BS1 = CAN_BS1_12tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_8tq;
  CAN_InitStructure.CAN_Prescaler = 4;
  CAN_Init(CANx, &CAN_InitStructure);
 
  /* CAN filter init */
  CAN_FilterInitStructure.CAN_FilterNumber = 0;
  CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterIdHigh = 0x0000;
  CAN_FilterInitStructure.CAN_FilterIdLow = 0x0000;
  CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0x0000;
  CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0x0000;
  CAN_FilterInitStructure.CAN_FilterFIFOAssignment = 0;
  CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;
  CAN_FilterInit(&CAN_FilterInitStructure);
  
  /* Transmit Structure preparation */
//  TxMessage.StdId = 0x300;
  TxMessage.ExtId = 0x01;
  TxMessage.RTR = CAN_RTR_DATA;
  TxMessage.IDE = CAN_ID_STD;
  TxMessage.DLC = 8;
//  TxMessage.Data[0] = 0x00;
  
  /* Enable FIFO 0 message pending Interrupt */
  CAN_ITConfig(CANx, CAN_IT_FMP0, ENABLE);
    
    NVIC_InitStructure.NVIC_IRQChannel = CAN1_RX0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x1;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
 
}

 

 

void CANBusTaskID3FFh(void){
 
    TxMessage.StdId = 0x3FF;
 
    TxMessage.Data[0] = 0x00;
    TxMessage.Data[1] = 0x00;
    TxMessage.Data[2] = 0x00;
    TxMessage.Data[3] = 0x00;
    TxMessage.Data[4] = (((uint16_t)(CC*80)) & 0xFF00) >> 8; //MSB
    TxMessage.Data[5] = ((uint16_t)(CC*80)) & 0x00FF; //LSB
    TxMessage.Data[6] = (((uint16_t)(DC*50))& 0xFF00) >> 8; //MSB;
    TxMessage.Data[7] = ((uint16_t)(DC*50)) & 0x00FF; //LSB;
 
 
    StatusCAN = CAN_Transmit(CAN1,&TxMessage);
 
    CanBusTxFailureCounter = 0;
    while((CAN_TransmitStatus(CAN1, StatusCAN) != CANTXOK) && (CanBusTxFailureCounter != CanBusTxFailureCounterMax) ) // Wait on Transmit
  {
        CanBusTxFailureCounter++;
    }
}

 

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