Issue with CAN in loopback mode

[Erwan03]

Hello, i am using f446re nucleo board and have been facing a problem for a while now. I need to establish a loopback CAN transmission and the debug mode allows me to find a bug in the CAN Start function: HAL_ERROR 0x1 returned everytime i attempt.

here is the while loop i am talking about:

while((hcan->Instance->MSR & CAN_MSR_INAK) != 0)

{

  if((HAL_GetTick() -tickstart) > CAN_TIMEOUT_VALUE)

  {

    hcan->ErrorCode |= HAL_CAN_ERROR_TIMEOUT;

    hcan->State = HAL_CAN_STATE_ERROR;

    return HAL_ERROR;

  }

}

[SofLit]

Hello,

Could you please share your code or your ioc file if you're using CubeMx?

Share the GPIO pin configurations.

[Erwan03]

Thank you for your quick answer!

Here is the GPIO config from the .ioc

[SofLit]

I need your ioc file. please attach it.

[Erwan03]

here is the file. Sorry i clicked on the Accept as Solution but did not wanted to. Missclick.

[SofLit · Accepted solution]

Configure CAN_Rx pin (PA11) in pullup mode:

[Erwan03]

Thank you for your help. I don,t know how come this worked but it did.

Another problem i am facing is i am trying to display the frame using the picoscope. I Wrote a function that initialise the Header Struct, and send the data, but nothing on the screen, can you help me one more time? he re is the function i wrote: 

void CAN_send(void)

{

char msg[50];

CAN_TxHeaderTypeDef TxHeader;

uint8_t TxData[4] = {'T','E','S','T'};

TxHeader.DLC = 4; // 4 data byte

TxHeader.ExtId = 0; // Not used so far

TxHeader.IDE = CAN_ID_STD; // Standard ID

TxHeader.RTR = CAN_RTR_DATA; // Data and not remote frame

TxHeader.StdId = 0x103; // Data ID

TxHeader.TransmitGlobalTime = DISABLE;

if(HAL_CAN_AddTxMessage(&hcan1, &TxHeader, TxData, &TxMailbox)!=HAL_OK)

{

Error_Handler();

}

while( HAL_CAN_IsTxMessagePending(&hcan1, TxMailbox));

sprintf(msg, "Message transmitted\r\n");

HAL_UART_Transmit(&huart2, (uint8_t*)msg, strlen(msg), HAL_MAX_DELAY);

}

[SofLit]

Hello,

Since the original question was answered, I invite you to open a new thread and tag me there, I will gladly help you on this new question .