I am trying to get CAN working on the stm32f0discovery. I have hooked up a transceiver on PB8 and PB9. I have written some basic code with the STM32Cube help. But I cant get transmitting or receiving working. I have probed the pins and I can see that there are messages being received on the RX pin (PB8). I cant see anything on PB9 so I am sure it is not the transceiver.
Please look over my code and see what I am missing.
Here is my main.c:
#include "main.h"
CAN_HandleTypeDef hcan;
CAN_FilterTypeDef filter;
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_CAN_Init(void);
void CAN_Tx(void);
void CAN_Tx(void){
CAN_TxHeaderTypeDef TxHeader;
uint8_t msg[8] = {'M','E','S', 'S', 'A', 'G', 'E'};
uint32_t TxMailBox;
TxHeader.DLC= 7;
TxHeader.StdId=0x65D;
TxHeader.IDE= CAN_ID_STD;
TxHeader.RTR= CAN_RTR_DATA;
if(HAL_CAN_AddTxMessage(&hcan, &TxHeader, msg , &TxMailBox)!= HAL_OK)
{
Error_Handler();
}
while(HAL_CAN_IsTxMessagePending(&hcan, TxMailBox));
}
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_CAN_Init();
/* USER CODE BEGIN 2 */
HAL_CAN_Start(&hcan);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
//CAN_Tx();
if(HAL_CAN_GetRxFifoFillLevel(&hcan, CAN_RX_FIFO0)){
CAN_RxHeaderTypeDef rx_msg;
uint8_t aData[8];
HAL_CAN_GetRxMessage(&hcan, CAN_RX_FIFO0, &rx_msg, aData);
}
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Initializes the CPU, AHB and APB busses clocks
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48;
RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB busses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI48;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
{
Error_Handler();
}
HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);
HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}
/**
* @brief CAN Initialization Function
* @param None
* @retval None
*/
static void MX_CAN_Init(void)
{
/* USER CODE BEGIN CAN_Init 0 */
/* USER CODE END CAN_Init 0 */
/* USER CODE BEGIN CAN_Init 1 */
/* USER CODE END CAN_Init 1 */
hcan.Instance = CAN;
hcan.State = HAL_CAN_STATE_RESET;
hcan.Init.Prescaler = 16;
hcan.Init.Mode = CAN_MODE_NORMAL;
hcan.Init.SyncJumpWidth = CAN_SJW_2TQ;
hcan.Init.TimeSeg1 = CAN_BS1_4TQ;
hcan.Init.TimeSeg2 = CAN_BS2_2TQ;
hcan.Init.TimeTriggeredMode = DISABLE;
hcan.Init.AutoBusOff = DISABLE;
hcan.Init.AutoWakeUp = DISABLE;
hcan.Init.AutoRetransmission = ENABLE;
hcan.Init.ReceiveFifoLocked = DISABLE;
hcan.Init.TransmitFifoPriority = DISABLE;
if (HAL_CAN_Init(&hcan) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN CAN_Init 2 */
filter.FilterIdHigh = 0;
filter.FilterIdLow = 0;
filter.FilterMaskIdHigh = 0;
filter.FilterMaskIdLow = 0;
filter.FilterMode = CAN_FILTERMODE_IDMASK;
filter.FilterScale = CAN_FILTERSCALE_32BIT;
filter.FilterBank = 0;
filter.FilterFIFOAssignment = CAN_RX_FIFO0;
filter.FilterActivation = ENABLE;
HAL_CAN_ConfigFilter(&hcan, &filter);
/* USER CODE END CAN_Init 2 */
}
/**
* @brief GPIO Initialization Function
* @param None
* @retval None
*/
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOC_CLK_ENABLE();
__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOC, NCS_MEMS_SPI_Pin|EXT_RESET_Pin|LD3_Pin|LD6_Pin
|LD4_Pin|LD5_Pin, GPIO_PIN_RESET);
/*Configure GPIO pins : NCS_MEMS_SPI_Pin EXT_RESET_Pin LD3_Pin LD6_Pin
LD4_Pin LD5_Pin */
GPIO_InitStruct.Pin = NCS_MEMS_SPI_Pin|EXT_RESET_Pin|LD3_Pin|LD6_Pin
|LD4_Pin|LD5_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
/*Configure GPIO pins : MEMS_INT1_Pin MEMS_INT2_Pin */
GPIO_InitStruct.Pin = MEMS_INT1_Pin|MEMS_INT2_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_EVT_RISING;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
/*Configure GPIO pin : B1_Pin */
GPIO_InitStruct.Pin = B1_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_EVT_RISING;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(B1_GPIO_Port, &GPIO_InitStruct);
/*Configure GPIO pins : PA2 PA3 PA6 PA7 */
GPIO_InitStruct.Pin = GPIO_PIN_2|GPIO_PIN_3|GPIO_PIN_6|GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF3_TSC;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/*Configure GPIO pins : PB0 PB1 */
GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF3_TSC;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/*Configure GPIO pins : I2C2_SCL_Pin I2C2_SDA_Pin */
GPIO_InitStruct.Pin = I2C2_SCL_Pin|I2C2_SDA_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_AF_OD;
GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF1_I2C2;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/*Configure GPIO pins : SPI2_SCK_Pin SPI2_MISO_Pin SPI2_MOSI_Pin */
GPIO_InitStruct.Pin = SPI2_SCK_Pin|SPI2_MISO_Pin|SPI2_MOSI_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF0_SPI2;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
}
/* USER CODE BEGIN 4 */
/* USER CODE END 4 */
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
and my stm32f0xx_hal_msp.c
void HAL_MspInit(void)
{
/* USER CODE BEGIN MspInit 0 */
/* USER CODE END MspInit 0 */
__HAL_RCC_SYSCFG_CLK_ENABLE();
__HAL_RCC_PWR_CLK_ENABLE();
/* System interrupt init*/
HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
/* USER CODE BEGIN MspInit 1 */
/* USER CODE END MspInit 1 */
}
/**
* @brief CAN MSP Initialization
* This function configures the hardware resources used in this example
* @param hcan: CAN handle pointer
* @retval None
*/
void HAL_CAN_MspInit(CAN_HandleTypeDef* hcan)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(hcan->Instance==CAN)
{
/* USER CODE BEGIN CAN_MspInit 0 */
/* USER CODE END CAN_MspInit 0 */
/* Peripheral clock enable */
__HAL_RCC_CAN1_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
/**CAN GPIO Configuration
PB8 ------> CAN_RX
PB9 ------> CAN_TX
*/
GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF4_CAN;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* USER CODE BEGIN CAN_MspInit 1 */
/* USER CODE END CAN_MspInit 1 */
}
}
