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 */
}

[Karl Yamashita]

You haven't mentioned what you're trying to send a CAN message to? If you haven't connect your CAN wires to any other CAN bus, then you'll get transmit error.

[SofLit]

Hello, 

Three things to check:

• Is there a second node connected on the other side of the bus? As the sender needs an acknowledgement from at least one node on the bus.
• If yes, are you using HSE or HSI as system clock source?
• Did you set the same bitrate at both sides (the two nodes)?

[JDOG]

I have a Pcan Dongle hooked up and it is configured to 250Kbits per second and I have verified that it is working with hardware that is transmitting messages.

The bit rate is set at both places at 250 Kbits per second

Yes I am using the HSE as clock source.

The 1 ms clock tick is being generated from a PLL clock so I know the clocks are working off of the 8 Mhz clock

When I send the transmit message I  get the CAN error on channel 6 Blue Trace.

[Karl Yamashita]

upload your ioc file

[SofLit]

Check also your connections and wiring by doing continuity tests.

What about the termination resistors? Is there a termination resistor inside the PCAN? I don't seen one on the schematics above! You need only two termination resistors of 120ohm on each side of the bus .

Could you please also provide a diagram of your connections including the perceivers and the termination resistors to have a clear view of your HW?

[JDOG]

I Attached the *.ioc file as requested.

[SofLit]

---

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)

[Karl Yamashita]

Based off your ABP1 clock, you'll need these settings for 250kbs

[JDOG]

The 120 ohm terminator at the CANH and CANL side of the Transceiver is attached with soldering the wires to the (greeen and yellow wires).

There is a terminator in the PCan dongle as well.