1定义时钟
2定义按键
按键上拉电阻
3开启串口
4打开CAN（具体什么意思上一篇讲了）
5生成代码
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* Copyright (c) 2024 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 "main.h"
#include "can.h"
#include "usart.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "stdio.h"
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/**
* CAN 发送一组数据
* 数据 长度
*/
uint8_t can_send_msg( uint8_t *data, uint8_t len )
{
//发的结构体
CAN_TxHeaderTypeDef can_tx;
can_tx.DLC=len; // 数据长度代码
can_tx.ExtId=0x00;// 扩展标识符
can_tx.IDE=CAN_ID_EXT;// 标识符类型为扩展帧 //标识符的长度
can_tx.RTR=CAN_RTR_DATA;// 远程传输请求为数据帧
can_tx.StdId=0x12;// 标准标识符 //can的ID
//can_tx.TransmitGlobalTime=ENABLE;// 使用全局时间 ENABLE开启 DISABLE关闭 时间戳
uint32_t as=CAN_TX_MAILBOX0;
if(HAL_CAN_AddTxMessage(&hcan,&can_tx,data,&as)==HAL_OK){
int as1=HAL_CAN_GetTxMailboxesFreeLevel(&hcan);
char aa[28];
sprintf(aa,"数据发送成功,邮箱个数为：%d\n",as1);
HAL_UART_Transmit(&huart1,(uint8_t*)aa,27,50);
}
while (HAL_CAN_GetTxMailboxesFreeLevel(&hcan) != 3); /* 等待发送完成,所有邮箱为空 */
return 0;
}
/**
* CAN 接收数据查询
// 数据
*/
void can_receive_msg( uint8_t *data )
{
//接收的结构体
// 声明一个变量来存储接收到的消息的头部信息
CAN_RxHeaderTypeDef can_rx;
//can_rx.DLC // 数据长度
//can_rx.ExtId //扩展标识符
//can_rx.FilterMatchIndex// 过滤器匹配索引
//can_rx.IDE // 标识符类型为扩展帧
//can_rx.RTR // 远程传输请求为数据帧
//can_rx.StdId; // 标准标识符
//can_rx.Timestamp ; // 时间戳
if(HAL_CAN_GetRxMessage(&hcan, CAN_RX_FIFO0, &can_rx, data)== HAL_OK)
{
char aa[28]={"接收成功\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)aa,9,50);
}else{
char aa[28]={"接收失败\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)aa,9,50);
}
}
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
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();
MX_USART1_UART_Init();
/* USER CODE BEGIN 2 */
CAN_FilterTypeDef sFilterConfig;
//配置CAN过滤器
sFilterConfig.FilterBank = 0; /* 过滤器0 */
sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK;
sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT;
sFilterConfig.FilterIdHigh = 0x0000; /* 32位ID */
sFilterConfig.FilterIdLow = 0x0000;
sFilterConfig.FilterMaskIdHigh = 0x0000; /* 32位MASK */
sFilterConfig.FilterMaskIdLow = 0x0000;
sFilterConfig.FilterFIFOAssignment = CAN_FILTER_FIFO0; /* 过滤器0关联到FIFO0 */
sFilterConfig.FilterActivation = CAN_FILTER_ENABLE; /* 激活滤波器0 */
sFilterConfig.SlaveStartFilterBank = 14;
// 过滤器配置
if ( HAL_CAN_ConfigFilter( &hcan, &sFilterConfig ) != HAL_OK )
{
return 2;
}
// 启动CAN外围设备
if ( HAL_CAN_Start( &hcan ) != HAL_OK )
{
return 3;
}
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_4)== GPIO_PIN_SET){
HAL_Delay(20);
if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_4)==HAL_OK){
char a[]={"按键按下了\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)a,11,50);
uint8_t tx_data[8] = {"ABCDEFGH"}; // 消息数据
uint8_t rx_data[8]; // 接收数据缓冲区
can_send_msg( tx_data, 8 );
if(HAL_CAN_GetRxFifoFillLevel(&hcan ,CAN_RX_FIFO0)){
can_receive_msg( rx_data );
}else{
char aa[28]={"无数据\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)aa,9,50);
}
HAL_Delay(500);
HAL_UART_Transmit(&huart1,rx_data,8,500);
}
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* 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 RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
}
/* 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 */
__disable_irq();
while (1)
{
}
/* 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,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
6编写过程
1编写接收函数
**
* CAN 接收数据查询
// 数据
*/
void can_receive_msg( uint8_t *data )
{
//接收的结构体
// 声明一个变量来存储接收到的消息的头部信息
CAN_RxHeaderTypeDef can_rx;
//can_rx.DLC // 数据长度
//can_rx.ExtId //扩展标识符
//can_rx.FilterMatchIndex// 过滤器匹配索引
//can_rx.IDE // 标识符类型为扩展帧
//can_rx.RTR // 远程传输请求为数据帧
//can_rx.StdId; // 标准标识符
//can_rx.Timestamp ; // 时间戳
if(HAL_CAN_GetRxMessage(&hcan, CAN_RX_FIFO0, &can_rx, data)== HAL_OK)
{
char aa[28]={"接收成功\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)aa,9,50);
}else{
char aa[28]={"接收失败\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)aa,9,50);
}
}2编写发送函数
/**
* CAN 发送一组数据
* 数据 长度
*/
uint8_t can_send_msg( uint8_t *data, uint8_t len )
{
//发的结构体
CAN_TxHeaderTypeDef can_tx;
can_tx.DLC=len; // 数据长度代码
can_tx.ExtId=0x00;// 扩展标识符
can_tx.IDE=CAN_ID_EXT;// 标识符类型为扩展帧 //标识符的长度
can_tx.RTR=CAN_RTR_DATA;// 远程传输请求为数据帧
can_tx.StdId=0x12;// 标准标识符 //can的ID
//can_tx.TransmitGlobalTime=ENABLE;// 使用全局时间 ENABLE开启 DISABLE关闭 时间戳
uint32_t as=CAN_TX_MAILBOX0;
if(HAL_CAN_AddTxMessage(&hcan,&can_tx,data,&as)==HAL_OK){
int as1=HAL_CAN_GetTxMailboxesFreeLevel(&hcan);
char aa[28];
sprintf(aa,"数据发送成功,邮箱个数为：%d\n",as1);
HAL_UART_Transmit(&huart1,(uint8_t*)aa,27,50);
}
while (HAL_CAN_GetTxMailboxesFreeLevel(&hcan) != 3); /* 等待发送完成,所有邮箱为空 */
return 0;
}
3配置过滤器（不配置不可接收数据）
CAN_FilterTypeDef sFilterConfig;
//配置CAN过滤器
sFilterConfig.FilterBank = 0; /* 过滤器0 */
sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK;
sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT;
sFilterConfig.FilterIdHigh = 0x0000; /* 32位ID */
sFilterConfig.FilterIdLow = 0x0000;
sFilterConfig.FilterMaskIdHigh = 0x0000; /* 32位MASK */
sFilterConfig.FilterMaskIdLow = 0x0000;
sFilterConfig.FilterFIFOAssignment = CAN_FILTER_FIFO0; /* 过滤器0关联到FIFO0 */
sFilterConfig.FilterActivation = CAN_FILTER_ENABLE; /* 激活滤波器0 */
sFilterConfig.SlaveStartFilterBank = 14;
// 过滤器配置
if ( HAL_CAN_ConfigFilter( &hcan, &sFilterConfig ) != HAL_OK )
{
return 2;
}
// 启动CAN外围设备
if ( HAL_CAN_Start( &hcan ) != HAL_OK )
{
return 3;
}4编写按键实现收发数据
while (1)
{
if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_4)== GPIO_PIN_SET){
HAL_Delay(20);
if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_4)==HAL_OK){
char a[]={"按键按下了\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)a,11,50);
uint8_t tx_data[8] = {"ABCDEFGH"}; // 消息数据
uint8_t rx_data[8]; // 接收数据缓冲区
can_send_msg( tx_data, 8 );
if(HAL_CAN_GetRxFifoFillLevel(&hcan ,CAN_RX_FIFO0)){
can_receive_msg( rx_data );
}else{
char aa[28]={"无数据\n"};
HAL_UART_Transmit(&huart1,(uint8_t*)aa,9,50);
}
HAL_Delay(500);
HAL_UART_Transmit(&huart1,rx_data,8,500);
}
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}效果
注意
1过滤器
主页中有免费的CAN资料和项目文件
