CAN Communication issue with STM32F4

[JDOG]

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    can.c
  * @brief   This file provides code for the configuration
  *          of the CAN instances.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "can.h"
#include "main.h"
 
#include "usart.h"
 
CAN_HandleTypeDef hcan2;
 
static CAN_TxHeaderTypeDef   TxHeader;
static CAN_RxHeaderTypeDef   RxHeader;
static uint8_t               TxData[8];
static uint8_t               RxData[8];
static uint32_t              TxMailbox;
 
static char           Print_buffer[200];
 
#define CAN_BAUD_250K 8 // Prescaler for 250 Kbits per second
#define CAN_BAUD_500K 4 // Prescaler for 500 Kbits per second
 
 
/* CAN2 init function */
void MX_CAN2_Init(void)
{
HAL_StatusTypeDef HAL_error;
CAN_FilterTypeDef  sFilterConfig;
 
  /*##-1- Configure the CAN peripheral #######################################*/
hcan2.Instance = CAN2;
hcan2.Init.Prescaler = CAN_BAUD_250K;
hcan2.Init.Mode = CAN_MODE_LOOPBACK; //CAN_MODE_NORMAL;
hcan2.Init.SyncJumpWidth = CAN_SJW_1TQ;
hcan2.Init.TimeSeg1 = CAN_BS1_16TQ;
hcan2.Init.TimeSeg2 = CAN_BS2_8TQ;
hcan2.Init.TimeTriggeredMode = DISABLE;
hcan2.Init.AutoBusOff = DISABLE;
hcan2.Init.AutoWakeUp = ENABLE;
hcan2.Init.AutoRetransmission = ENABLE;
hcan2.Init.ReceiveFifoLocked = DISABLE;
hcan2.Init.TransmitFifoPriority = DISABLE;
 
  HAL_error = HAL_CAN_Init(&hcan2);
 
  if (HAL_error != HAL_OK)
  {
    Error_Handler(HAL_error);
  }
 
  /*##-2- Configure the CAN Filter ###########################################*/
  sFilterConfig.FilterBank = 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_RX_FIFO0;
  sFilterConfig.FilterActivation = ENABLE;
  sFilterConfig.SlaveStartFilterBank = 14;
 
  HAL_error = HAL_CAN_ConfigFilter(&hcan2, &sFilterConfig);
 
  if (HAL_error != HAL_OK)
  {
    Error_Handler(HAL_error);
  }
 
  /*##-3- Start the CAN peripheral ###########################################*/
  HAL_error = HAL_CAN_Start(&hcan2);
 
  if (HAL_error != HAL_OK)
  {
  Error_Handler(HAL_error);
  }
 
  /*##-4- Activate CAN RX notification #######################################*/
  HAL_error = HAL_CAN_ActivateNotification(&hcan2, CAN_IT_RX_FIFO0_MSG_PENDING);
 
  if (HAL_error != HAL_OK)
  {
  Error_Handler(HAL_error);
  }
}
 
void HAL_CAN_MspInit(CAN_HandleTypeDef* canHandle)
{
 
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(canHandle->Instance==CAN2)
  {
  /* USER CODE BEGIN CAN2_MspInit 0 */
 
  /* USER CODE END CAN2_MspInit 0 */
    /* CAN2 clock enable */
   // __HAL_RCC_CAN1_CLK_ENABLE();
    __HAL_RCC_CAN2_CLK_ENABLE();
 
    __HAL_RCC_GPIOB_CLK_ENABLE();
    /**CAN2 GPIO Configuration
    PB12     ------> CAN2_RX
    PB13     ------> CAN2_TX
    */
    GPIO_InitStruct.Pin = GPIO_PIN_13;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF9_CAN2;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
 
    GPIO_InitStruct.Pin = GPIO_PIN_12;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_PULLUP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF9_CAN2;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
 
    /* CAN2 interrupt Init */
    HAL_NVIC_SetPriority(CAN2_TX_IRQn, 5, 0);
    HAL_NVIC_EnableIRQ(CAN2_TX_IRQn);
 
    HAL_NVIC_SetPriority(CAN2_RX0_IRQn, 5, 0);
 
    //HAL_NVIC_EnableIRQ(CAN2_RX0_IRQn);
 
    HAL_NVIC_SetPriority(CAN2_RX1_IRQn, 5, 0);
    //HAL_NVIC_EnableIRQ(CAN2_RX1_IRQn);
 
    HAL_NVIC_SetPriority(CAN2_SCE_IRQn, 5, 0);
    HAL_NVIC_EnableIRQ(CAN2_SCE_IRQn);
  /* USER CODE BEGIN CAN2_MspInit 1 */
 
  /* USER CODE END CAN2_MspInit 1 */
  }
}
 
void HAL_CAN_MspDeInit(CAN_HandleTypeDef* canHandle)
{
 
  if(canHandle->Instance==CAN2)
  {
  /* USER CODE BEGIN CAN2_MspDeInit 0 */
 
  /* USER CODE END CAN2_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_CAN1_CLK_DISABLE();
    __HAL_RCC_CAN2_CLK_DISABLE();
 
    /**CAN2 GPIO Configuration
    PB12     ------> CAN2_RX
    PB13     ------> CAN2_TX
    */
    HAL_GPIO_DeInit(GPIOB, GPIO_PIN_12|GPIO_PIN_13);
 
    /* CAN2 interrupt Deinit */
    HAL_NVIC_DisableIRQ(CAN2_TX_IRQn);
    HAL_NVIC_DisableIRQ(CAN2_RX0_IRQn);
    HAL_NVIC_DisableIRQ(CAN2_RX1_IRQn);
    HAL_NVIC_DisableIRQ(CAN2_SCE_IRQn);
  /* USER CODE BEGIN CAN2_MspDeInit 1 */
 
  /* USER CODE END CAN2_MspDeInit 1 */
  }
}
 
 
/**
  * @brief  Rx Fifo 0 message pending callback
  *   hcan: pointer to a CAN_HandleTypeDef structure that contains
  *         the configuration information for the specified CAN.
  * @retval None
  */
void HAL_CAN_RxFifo0MsgPendingCallback(CAN_HandleTypeDef *hcan)
{
  HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_0);
 
  /* Get RX message */
  if (HAL_CAN_GetRxMessage(hcan, CAN_RX_FIFO0, &RxHeader, RxData) != HAL_OK)
  {
sprintf(Print_buffer, "CAN Read Error!\r\n");
uart_print(Print_buffer);
  }
  else
  {
sprintf(Print_buffer, "StdID: 0x%lX, IDE: 0x%lX , ExtId: 0x%lX, FMI: 0x%lX, RTR: 0x%lX, DLC: 0x%lX, TS: 0x%lX \r\n", RxHeader.StdId, RxHeader.IDE, RxHeader.ExtId,
RxHeader.FilterMatchIndex, RxHeader.RTR, RxHeader.DLC, RxHeader.Timestamp);
uart_print(Print_buffer);
 
sprintf(Print_buffer, "Data: 0x%X,0x%X,0x%X,0x%X,0x%X,0x%X,0x%X,0x%X \r\n", RxData[0], RxData[1], RxData[2], RxData[3],
RxData[4], RxData[5], RxData[6], RxData[7]);
uart_print(Print_buffer);
 
  }
}
 
void ReportCAN_Status(void)
{
HAL_StatusTypeDef HAL_error;
CAN_HandleTypeDef *can_handle = &hcan2;
 
uint32_t interrupts = READ_REG(can_handle->Instance->IER);
  uint32_t msrflags = READ_REG(can_handle->Instance->MSR);
  uint32_t tsrflags = READ_REG(can_handle->Instance->TSR);
  uint32_t rf0rflags = READ_REG(can_handle->Instance->RF0R);
  uint32_t rf1rflags = READ_REG(can_handle->Instance->RF1R);
  uint32_t esrflags = READ_REG(can_handle->Instance->ESR);
 
sprintf(Print_buffer, "Interrupts: 0x%lX, msr flags: 0x%lX , tsr flags: 0x%lX, rf0r flags: 0x%lX, rf1r flags: 0x%lX, esr flags: 0x%lX \r\n",
interrupts, msrflags, tsrflags, rf0rflags, rf1rflags, esrflags);
uart_print(Print_buffer);
 
CLEAR_BIT(can_handle->Instance->MSR, CAN_MSR_WKUI);
 
interrupts = READ_REG(can_handle->Instance->IER);
msrflags = READ_REG(can_handle->Instance->MSR);
tsrflags = READ_REG(can_handle->Instance->TSR);
    rf0rflags = READ_REG(can_handle->Instance->RF0R);
rf1rflags = READ_REG(can_handle->Instance->RF1R);
esrflags = READ_REG(can_handle->Instance->ESR);
 
sprintf(Print_buffer, "Interrupts: 0x%lX,msr flags: 0x%lX,tsr flags: 0x%lX,rf0r flags: 0x%lX,rf1r flags: 0x%lX,esr flags: 0x%lX \r\n",
interrupts, msrflags, tsrflags, rf0rflags, rf1rflags, esrflags);
uart_print(Print_buffer);
 
}
 
void SendCAN_Message(void)
{
HAL_StatusTypeDef HAL_error;
CAN_HandleTypeDef *can_handle = &hcan2;
 
uint32_t interrupts = READ_REG(can_handle->Instance->IER);
  uint32_t msrflags = READ_REG(can_handle->Instance->MSR);
  uint32_t tsrflags = READ_REG(can_handle->Instance->TSR);
  uint32_t rf0rflags = READ_REG(can_handle->Instance->RF0R);
  uint32_t rf1rflags = READ_REG(can_handle->Instance->RF1R);
  uint32_t esrflags = READ_REG(can_handle->Instance->ESR);
 
  TxHeader.StdId = 0;
  TxHeader.ExtId = 0x01FF0060;
  TxHeader.RTR = CAN_RTR_DATA;
  TxHeader.IDE = CAN_ID_EXT;
  TxHeader.DLC = 8;
  TxHeader.TransmitGlobalTime = ENABLE;
 
  TxData[0] = 0x01;
  TxData[1] = 0x12;
  TxData[0] = 0x28;
  TxData[0] = 0x20;
  TxData[0] = 0x16;
  TxData[0] = 0x05;
  TxData[0] = 0x00;
  TxData[0] = 0x02;
 
  HAL_error = HAL_CAN_AddTxMessage(&hcan2, &TxHeader, TxData, &TxMailbox);
 
  if (HAL_error != HAL_OK)
  {
  Error_Handler(HAL_error);
  }
}

When I set the CAN Mode to LOOP BACK the transmission works fine.

Interrupts: 0x2, msr flags: 0xC08 , tsr flags: 0x1C000003, rf0r flags: 0x0, rf1r flags: 0x0, esr flags: 0x0
Interrupts: 0x2,msr flags: 0xC08,tsr flags: 0x1C000003,rf0r flags: 0x0,rf1r flags: 0x0,esr flags: 0x0

When I run the same code in Normal Mode The same transmit message fails.

hcan2.Init.Mode = CAN_MODE_NORMAL;

Interrupts: 0x2, msr flags: 0xC08 , tsr flags: 0x19000008, rf0r flags: 0x0, rf1r flags: 0x0, esr flags: 0xF80057
Interrupts: 0x2,msr flags: 0xC08,tsr flags: 0x19000008,rf0r flags: 0x0,rf1r flags: 0x0,esr flags: 0xF80057

I have to assume that my transceiver must be the problem.

Can2 has another port pin but I think I selected the GPIO ports correctly.

void HAL_CAN_MspInit(CAN_HandleTypeDef* canHandle)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};

if(canHandle->Instance==CAN2)
{
/* USER CODE BEGIN CAN2_MspInit 0 */

/* USER CODE END CAN2_MspInit 0 */
/* CAN2 clock enable */

// __HAL_RCC_CAN1_CLK_ENABLE();

__HAL_RCC_CAN2_CLK_ENABLE();
 
__HAL_RCC_GPIOB_CLK_ENABLE();

/**CAN2 GPIO Configuration
PB12 ------> CAN2_RX

PB13 ------> CAN2_TX

*/

GPIO_InitStruct.Pin = GPIO_PIN_13;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF9_CAN2;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
 

GPIO_InitStruct.Pin = GPIO_PIN_12;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF9_CAN2;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);


/* CAN2 interrupt Init */

HAL_NVIC_SetPriority(CAN2_TX_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(CAN2_TX_IRQn);
HAL_NVIC_SetPriority(CAN2_RX0_IRQn, 5, 0);

//HAL_NVIC_EnableIRQ(CAN2_RX0_IRQn);
HAL_NVIC_SetPriority(CAN2_RX1_IRQn, 5, 0);
//HAL_NVIC_EnableIRQ(CAN2_RX1_IRQn);

HAL_NVIC_SetPriority(CAN2_SCE_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(CAN2_SCE_IRQn);

/* USER CODE BEGIN CAN2_MspInit 1 */

/* USER CODE END CAN2_MspInit 1 */
}

[SofLit]

Hello,

Not sure I can see the resistor but ok.

Now please check your bitrate and see my previous comment:

"

I have a Pcan Dongle hooked up and it is configured to 250Kbits per second and I have verified

You said you configured your PCAN at 250kb/s but from your ioc file the bitrate is set at 500kb/s!

Could you please double check? (changing the Prescaler (for time Quantom) to 8 instead of 4)"

[JDOG]

I ordered an eval board for the ATA6560 transceiver and I will connect it to  my NUCLEO-F412ZG board and test the same CAN code that I have in our current PDM target board. The CAN is the last thing I need going to finish the Power Distribution Module (PDM) firmware for the first prototype.

[Karl Yamashita]

The STM32F412 uses CAN 2.0B protocol. Not that it won't work, but you don't need a CAN FD transceiver. Since you're using a Microchip product, use the MCP2551 transceiver. 

[SofLit]

---

@JDOG wrote:

I ordered an eval board for the ATA6560 transceiver and I will connect it to  my NUCLEO-F412ZG board

---

Referring to the ATA6560 datasheet, you may face an issue regarding the VIH level:

As I assume the MCU VDD is at 3.3V, the Tx level voltage can't exceed 3.3V for a recessive bit.

VIHmin of the transceiver = 0.7xVVIO. As ATA6560 version does not have VIO pin, VIO = VDD = 5V (power supply: VVCC = 4.5V to 5.5V).

--> VIHmin = 0.7 x 5 = 3.5V > 3.3V (the IO voltage max of the MCU). So the transceiver can't see high level on its Tx pin from your MCU!

[SofLit]

From voltage levels adaptation standpoint MCP2551 is good as VIH min = 2V:

But he can use FDCAN transceivers for CAN2.0 frames but he needs to think about the cost!

[Tobe]

Please show the analog signal.

[SofLit]

Hello @JDOG 

Did you solve the issue?

If yes, you need to share the solution in order to let other community members to benefit from it.

Or Click on "Accepted as Solution" on the reply which solved your issue or answered your question.

Thank you.

[JDOG]

We installed the new ATA6561 CAN transceiver and have the 3.3V on the VIO pin and VCC is connected to the 5.0V supply. I am not seeing any activity on the TX or Rx lines when I try to transmit from the Proto PCB or when I send a CAN message to the Proto PCB using my PCAN tool.

[SofLit · Accepted solution]

Hello your the selection of ATA6561 doesn't present an issue.

But since you're not seeing any activity on CAN_Tx pin of STM32, are you sure about the GPIO config? are you sure you selected the correct alternate function that connects CAN_TX to the transceiver?

You need to start at this point ..You need at least to have an activity on CAN_Tx.

[JDOG]

SofLit,

I started looking at the GPIO port pins and it turns out that between Me and the hardware designer we swapped the TX and Rx pins on the schematic. Going back and double checking the pin assignments in the ST32CubeMX tool helped point out the mistake.

Thanks for your help.