STM32F098 CAN works in loopback mode but not in normal mode

[SOsen.1]

Hello, for my personnal project I use a stm32F98 with the CAN peripheral activated.

First of all I have an issue with the configuraiton gave in the stm32f0_firmware example but if I set the GPIO_InitStruct.Pull to GPIO_NOPULL, I cannot have the INAK bit reset when going from initialization mode to Normal mode.

The solution to have it reset was to set GPIO_InitStruct.Pull to PullUp.

But then I had another issue : The peripheral do not receive/transmit any message.

When configured in LoopBack mode, it receives what it has just transmitted, so I assume that I have configured it well.

I've followed stm32f0_firmware example to configure bit timing and I have a 120ohm termination resistor right after the transceiver.

At this stage I really don't know what could cause this behaviour and I'm pretty lost..

[Tesla DeLorean]

In loop-back mode the speed settings are going to match, and you don't need a responding device on the bus.

No real data here to validate speed, clock, settings, or anything.

[SOsen.1]

I'm using a CAN232 dongle ( http://www.can232.com/?page_id=72 ) to read/write message on the bus from the ocmputer. I've configured the dongle speed to 1Mbit/s.

My STM32f0 settings are :

 /* USER CODE END CAN_Init 1 */

 hcan.Instance = CAN;

 hcan.Init.Prescaler = 4;

 hcan.Init.Mode = CAN_MODE_NORMAL;

 hcan.Init.SyncJumpWidth = CAN_SJW_1TQ;

 hcan.Init.TimeSeg1 = CAN_BS1_5TQ;

 hcan.Init.TimeSeg2 = CAN_BS2_6TQ;

 hcan.Init.TimeTriggeredMode = DISABLE;

 hcan.Init.AutoBusOff = DISABLE;

 hcan.Init.AutoWakeUp = DISABLE;

 hcan.Init.AutoRetransmission = DISABLE;

 hcan.Init.ReceiveFifoLocked = DISABLE;

 hcan.Init.TransmitFifoPriority = DISABLE;

 if (HAL_CAN_Init(&hcan) != HAL_OK)

 {

  Error_Handler();

 }

GPIO settings :

 GPIO_InitTypeDef GPIO_InitStruct = {0};

 if(canHandle->Instance==CAN)

 {

 /* USER CODE BEGIN CAN_MspInit 0 */

 /* USER CODE END CAN_MspInit 0 */

  /* CAN clock enable */

  __HAL_RCC_CAN1_CLK_ENABLE();

  __HAL_RCC_GPIOA_CLK_ENABLE();

  /**CAN GPIO Configuration

  PA11   ------> CAN_RX

  PA12   ------> CAN_TX

  */

  GPIO_InitStruct.Pin = GPIO_PIN_11|GPIO_PIN_12;

  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;

  GPIO_InitStruct.Pull = GPIO_PULLUP;//GPIO_NOPULL;

  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;

  GPIO_InitStruct.Alternate = GPIO_AF4_CAN;

  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

/* CAN interrupt Init */

HAL_NVIC_SetPriority(CEC_CAN_IRQn, 2, 0);

HAL_NVIC_EnableIRQ(CEC_CAN_IRQn);

 /* USER CODE BEGIN CAN_MspInit 1 */

By the way I've tried to catch frames with an oscilloscope but nothing comes out of the MCU.. Even if the timing was not good, I should see frames coming out of the TX pin don't I?