一、什么是任务通知
FreeRTOS 从版本 V8.2.0 开始提供任务通知这个功能,每个任务都有一个 32 位的通知值。按照 FreeRTOS 官方的说法,使用消息通知比通过二进制信号量方式解除阻塞任务快 45%, 并且更加省内存(无需创建队 列)。
在大多数情况下,任务通知可以替代二值信号量、计数信号量、事件标志组,可以替代长度为 1 的队列(可 以保存一个 32 位整数或指针值),并且任务通知速度更快、使用的RAM更少!
二、任务通知的更新方式
FreeRTOS 提供以下几种方式发送通知给任务 :
发送消息给任务,如果有通知未读, 不覆盖通知值
发送消息给任务,直接覆盖通知值
发送消息给任务,设置通知值的一个或者多个位
发送消息给任务,递增通知值
通过对以上方式的合理使用,可以在一定场合下替代原本的队列、信号量、事件标志组等。
三、任务通知的优势和劣势
3.1、任务通知的优势
1. 使用任务通知向任务发送事件或数据,比使用队列、事件标志组或信号量快得多。
2. 使用其他方法时都要先创建对应的结构体,使用任务通知时无需额外创建结构体。
3.2、任务通知的劣势
1. 只有任务可以等待通知,中断服务函数中不可以,因为中断没有 TCB 。
2. 通知只能一对一,因为通知必须指定任务。
3. 等待通知的任务可以被阻塞, 但是发送消息的任务,任何情况下都不会被阻塞等待。
4. 任务通知是通过更新任务通知值来发送数据的,任务结构体中只有一个任务通知值,只能保持一个数据。
四、相关函数
4.1、发送通知
BaseType_t xTaskNotify( TaskHandle_t xTaskToNotify,uint32_t ulValue,eNotifyAction eAction
);
参数:
xTaskToNotify:需要接收通知的任务句柄;
ulValue:用于更新接收任务通知值, 具体如何更新由形参 eAction 决定;
eAction:一个枚举,代表如何使用任务通知的值;
返回值:
如果被通知任务还没取走上一个通知,又接收了一个通知,则这次通知值未能更新并返回 pdFALSE, 而其他情况均返回pdPASS。
BaseType_t xTaskNotifyAndQuery( TaskHandle_t xTaskToNotify,uint32_t ulValue,eNotifyAction eAction,uint32_t * pulPreviousNotifyValue
);
参数:
xTaskToNotify:需要接收通知的任务句柄;
ulValue:用于更新接收任务通知值, 具体如何更新由形参 eAction 决定;
eAction:一个枚举,代表如何使用任务通知的值;
pulPreviousNotifyValue:对象任务的上一个任务通知值,如果为 NULL, 则不需要回传, 这个时候就等价于函数 xTaskNotify()。
返回值:
如果被通知任务还没取走上一个通知,又接收了一个通知,则这次通知值未能更新并返回 pdFALSE, 而其他 情况均返回pdPASS。
BaseType_t xTaskNotifyGive( TaskHandle_t xTaskToNotify );
参数:
xTaskToNotify:接收通知的任务句柄, 并让其自身的任务通知值加 1。
返回值:
总是返回 pdPASS。
4.2、等待通知
注意:等待通知API函数只能用在任务,不可应用于中断中!
uint32_t ulTaskNotifyTake( BaseType_t xClearCountOnExit,TickType_t xTicksToWait
);
参数:
xClearCountOnExit:指定在成功接收通知后,将通知值清零或减 1,pdTRUE:把通知值清零(二值信号量);pdFALSE:把通知值减一(计数型信号量);
xTicksToWait:阻塞等待任务通知值的最大时间;
返回值:
0:接收失败
非0:接收成功,返回任务通知的通知值
BaseType_t xTaskNotifyWait( uint32_t ulBitsToClearOnEntry,uint32_t ulBitsToClearOnExit,uint32_t * pulNotificationValue,TickType_t xTicksToWait
);
ulBitsToClearOnEntry:函数执行前清零任务通知值那些位 。
ulBitsToClearOnExit:表示在函数退出前,清零任务通知值那些位(最大值:0xFFFFFFFF),在清 0 前,接收到的任务通知值会先被 保存到形参*pulNotificationValue 中。
pulNotificationValue:用于保存接收到的任务通知值。 如果不需要使用,则设置为 NULL 即可 。 xTicksToWait:等待消息通知的最大等待时间。
五、实操
5.1、模拟二值信号量
按下 KEY1 则释放信号量,按下 KEY2 获取信号量。
/* USER CODE BEGIN Header */
/********************************************************************************* File Name : freertos.c* Description : Code for freertos applications******************************************************************************* @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 "FreeRTOS.h"
#include "task.h"
#include "main.h"
#include "cmsis_os.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 Variables *//* USER CODE END Variables */
osThreadId TaskKEY1Handle;
osThreadId TaskKEY2Handle;/* Private function prototypes -----------------------------------------------*/
/* USER CODE BEGIN FunctionPrototypes *//* USER CODE END FunctionPrototypes */void StartTaskKEY1(void const * argument);
void StartTaskKEY2(void const * argument);void MX_FREERTOS_Init(void); /* (MISRA C 2004 rule 8.1) *//* GetIdleTaskMemory prototype (linked to static allocation support) */
void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize );/* USER CODE BEGIN GET_IDLE_TASK_MEMORY */
static StaticTask_t xIdleTaskTCBBuffer;
static StackType_t xIdleStack[configMINIMAL_STACK_SIZE];void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize )
{*ppxIdleTaskTCBBuffer = &xIdleTaskTCBBuffer;*ppxIdleTaskStackBuffer = &xIdleStack[0];*pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;/* place for user code */
}
/* USER CODE END GET_IDLE_TASK_MEMORY *//*** @brief FreeRTOS initialization* @param None* @retval None*/
void MX_FREERTOS_Init(void) {/* USER CODE BEGIN Init *//* USER CODE END Init *//* USER CODE BEGIN RTOS_MUTEX *//* add mutexes, ... *//* USER CODE END RTOS_MUTEX *//* USER CODE BEGIN RTOS_SEMAPHORES *//* add semaphores, ... *//* USER CODE END RTOS_SEMAPHORES *//* USER CODE BEGIN RTOS_TIMERS *//* start timers, add new ones, ... *//* USER CODE END RTOS_TIMERS *//* USER CODE BEGIN RTOS_QUEUES *//* add queues, ... *//* USER CODE END RTOS_QUEUES *//* Create the thread(s) *//* definition and creation of TaskKEY1 */osThreadDef(TaskKEY1, StartTaskKEY1, osPriorityNormal, 0, 128);TaskKEY1Handle = osThreadCreate(osThread(TaskKEY1), NULL);/* definition and creation of TaskKEY2 */osThreadDef(TaskKEY2, StartTaskKEY2, osPriorityNormal, 0, 128);TaskKEY2Handle = osThreadCreate(osThread(TaskKEY2), NULL);/* USER CODE BEGIN RTOS_THREADS *//* add threads, ... *//* USER CODE END RTOS_THREADS */}/* USER CODE BEGIN Header_StartTaskKEY1 */
/*** @brief Function implementing the TaskKEY1 thread.* @param argument: Not used* @retval None*/
/* USER CODE END Header_StartTaskKEY1 */
void StartTaskKEY1(void const * argument)
{/* USER CODE BEGIN StartTaskKEY1 */BaseType_t mark = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){mark = xTaskNotifyGive( TaskKEY2Handle );if(mark == pdPASS)printf("任务通知模拟二值信号量发送成功!\r\n");elseprintf("任务通知模拟二值信号量发送失败!\r\n");}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskKEY1 */
}/* USER CODE BEGIN Header_StartTaskKEY2 */
/**
* @brief Function implementing the TaskKEY2 thread.
* @param argument: Not used
* @retval None
*/
/* USER CODE END Header_StartTaskKEY2 */
void StartTaskKEY2(void const * argument)
{/* USER CODE BEGIN StartTaskKEY2 */uint32_t flag = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){flag = ulTaskNotifyTake(pdTRUE ,0);if(flag != 0)printf("接收成功!任务的通知值为:%d\r\n",flag);elseprintf("接收失败!\r\n");}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskKEY2 */
}/* Private application code --------------------------------------------------*/
/* USER CODE BEGIN Application *//* USER CODE END Application */
5.2、模拟计数型信号量
按下 KEY1 则释放信号量,按下 KEY2 获取信号量。
/* USER CODE BEGIN Header */
/********************************************************************************* File Name : freertos.c* Description : Code for freertos applications******************************************************************************* @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 "FreeRTOS.h"
#include "task.h"
#include "main.h"
#include "cmsis_os.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 Variables *//* USER CODE END Variables */
osThreadId TaskKEY1Handle;
osThreadId TaskKEY2Handle;/* Private function prototypes -----------------------------------------------*/
/* USER CODE BEGIN FunctionPrototypes *//* USER CODE END FunctionPrototypes */void StartTaskKEY1(void const * argument);
void StartTaskKEY2(void const * argument);void MX_FREERTOS_Init(void); /* (MISRA C 2004 rule 8.1) *//* GetIdleTaskMemory prototype (linked to static allocation support) */
void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize );/* USER CODE BEGIN GET_IDLE_TASK_MEMORY */
static StaticTask_t xIdleTaskTCBBuffer;
static StackType_t xIdleStack[configMINIMAL_STACK_SIZE];void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize )
{*ppxIdleTaskTCBBuffer = &xIdleTaskTCBBuffer;*ppxIdleTaskStackBuffer = &xIdleStack[0];*pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;/* place for user code */
}
/* USER CODE END GET_IDLE_TASK_MEMORY *//*** @brief FreeRTOS initialization* @param None* @retval None*/
void MX_FREERTOS_Init(void) {/* USER CODE BEGIN Init *//* USER CODE END Init *//* USER CODE BEGIN RTOS_MUTEX *//* add mutexes, ... *//* USER CODE END RTOS_MUTEX *//* USER CODE BEGIN RTOS_SEMAPHORES *//* add semaphores, ... *//* USER CODE END RTOS_SEMAPHORES *//* USER CODE BEGIN RTOS_TIMERS *//* start timers, add new ones, ... *//* USER CODE END RTOS_TIMERS *//* USER CODE BEGIN RTOS_QUEUES *//* add queues, ... *//* USER CODE END RTOS_QUEUES *//* Create the thread(s) *//* definition and creation of TaskKEY1 */osThreadDef(TaskKEY1, StartTaskKEY1, osPriorityNormal, 0, 128);TaskKEY1Handle = osThreadCreate(osThread(TaskKEY1), NULL);/* definition and creation of TaskKEY2 */osThreadDef(TaskKEY2, StartTaskKEY2, osPriorityNormal, 0, 128);TaskKEY2Handle = osThreadCreate(osThread(TaskKEY2), NULL);/* USER CODE BEGIN RTOS_THREADS *//* add threads, ... *//* USER CODE END RTOS_THREADS */}/* USER CODE BEGIN Header_StartTaskKEY1 */
/*** @brief Function implementing the TaskKEY1 thread.* @param argument: Not used* @retval None*/
/* USER CODE END Header_StartTaskKEY1 */
void StartTaskKEY1(void const * argument)
{/* USER CODE BEGIN StartTaskKEY1 */BaseType_t mark = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){mark = xTaskNotifyGive( TaskKEY2Handle );if(mark == pdPASS)printf("任务通知模拟计数型信号量发送成功!\r\n");elseprintf("任务通知模拟计数型信号量发送失败!\r\n");}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskKEY1 */
}/* USER CODE BEGIN Header_StartTaskKEY2 */
/**
* @brief Function implementing the TaskKEY2 thread.
* @param argument: Not used
* @retval None
*/
/* USER CODE END Header_StartTaskKEY2 */
void StartTaskKEY2(void const * argument)
{/* USER CODE BEGIN StartTaskKEY2 */uint32_t flag = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){flag = ulTaskNotifyTake(pdFALSE ,0);if(flag != 0)printf("接收成功!任务的通知值为:%d\r\n",flag);elseprintf("接收失败!\r\n");}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskKEY2 */
}/* Private application code --------------------------------------------------*/
/* USER CODE BEGIN Application *//* USER CODE END Application */
5.3、模拟事件标志组
两个任务( task1 和 task2),task1 检测按键,如果检测到 KEY1 和 KEY2 都按过, 则执行 task2 。
/* USER CODE BEGIN Header */
/********************************************************************************* File Name : freertos.c* Description : Code for freertos applications******************************************************************************* @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 "FreeRTOS.h"
#include "task.h"
#include "main.h"
#include "cmsis_os.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 Variables *//* USER CODE END Variables */
osThreadId Task1Handle;
osThreadId Task2Handle;/* Private function prototypes -----------------------------------------------*/
/* USER CODE BEGIN FunctionPrototypes *//* USER CODE END FunctionPrototypes */void StartTask1(void const * argument);
void StartTask2(void const * argument);void MX_FREERTOS_Init(void); /* (MISRA C 2004 rule 8.1) *//* GetIdleTaskMemory prototype (linked to static allocation support) */
void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize );/* USER CODE BEGIN GET_IDLE_TASK_MEMORY */
static StaticTask_t xIdleTaskTCBBuffer;
static StackType_t xIdleStack[configMINIMAL_STACK_SIZE];void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize )
{*ppxIdleTaskTCBBuffer = &xIdleTaskTCBBuffer;*ppxIdleTaskStackBuffer = &xIdleStack[0];*pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;/* place for user code */
}
/* USER CODE END GET_IDLE_TASK_MEMORY *//*** @brief FreeRTOS initialization* @param None* @retval None*/
void MX_FREERTOS_Init(void) {/* USER CODE BEGIN Init *//* USER CODE END Init *//* USER CODE BEGIN RTOS_MUTEX *//* add mutexes, ... *//* USER CODE END RTOS_MUTEX *//* USER CODE BEGIN RTOS_SEMAPHORES *//* add semaphores, ... *//* USER CODE END RTOS_SEMAPHORES *//* USER CODE BEGIN RTOS_TIMERS *//* start timers, add new ones, ... *//* USER CODE END RTOS_TIMERS *//* USER CODE BEGIN RTOS_QUEUES *//* add queues, ... *//* USER CODE END RTOS_QUEUES *//* Create the thread(s) *//* definition and creation of Task1 */osThreadDef(Task1, StartTask1, osPriorityNormal, 0, 128);Task1Handle = osThreadCreate(osThread(Task1), NULL);/* definition and creation of Task2 */osThreadDef(Task2, StartTask2, osPriorityNormal, 0, 128);Task2Handle = osThreadCreate(osThread(Task2), NULL);/* USER CODE BEGIN RTOS_THREADS *//* add threads, ... *//* USER CODE END RTOS_THREADS */}/* USER CODE BEGIN Header_StartTask1 */
/*** @brief Function implementing the Task1 thread.* @param argument: Not used* @retval None*/
/* USER CODE END Header_StartTask1 */
void StartTask1(void const * argument)
{/* USER CODE BEGIN StartTask1 *//* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){printf("bit23位置1\r\n");xTaskNotifyAndQuery(Task2Handle ,0x800000 ,eSetBits ,NULL);}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET);}if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){printf("bit1与bit0位置1\r\n");xTaskNotifyAndQuery(Task2Handle ,0x3 ,eSetBits ,NULL); /*0011*/}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTask1 */
}/* USER CODE BEGIN Header_StartTask2 */
/**
* @brief Function implementing the Task2 thread.
* @param argument: Not used
* @retval None
*/
/* USER CODE END Header_StartTask2 */
void StartTask2(void const * argument)
{/* USER CODE BEGIN StartTask2 */uint32_t events = 0,result_bit = 0;/* Infinite loop */for(;;){xTaskNotifyWait(0 ,0xFFFFFFFF ,&events ,portMAX_DELAY);if(events & 0x800000)result_bit |= 0x800000;if(events & 0x3)result_bit |= 0x3;if(result_bit == (0x800000 | 0x3)){printf("请假成功,任务通知模拟事件标志组成功!\r\n");result_bit = 0;}osDelay(10);}/* USER CODE END StartTask2 */
}/* Private application code --------------------------------------------------*/
/* USER CODE BEGIN Application *//* USER CODE END Application */
5.4、模拟邮箱
邮箱是长度为1的队列
5.4.1、覆盖
/* USER CODE BEGIN Header */
/********************************************************************************* File Name : freertos.c* Description : Code for freertos applications******************************************************************************* @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 "FreeRTOS.h"
#include "task.h"
#include "main.h"
#include "cmsis_os.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 Variables *//* USER CODE END Variables */
osThreadId TaskSendHandle;
osThreadId TaskReceiveHandle;/* Private function prototypes -----------------------------------------------*/
/* USER CODE BEGIN FunctionPrototypes *//* USER CODE END FunctionPrototypes */void StartTaskSend(void const * argument);
void StartTaskReceive(void const * argument);void MX_FREERTOS_Init(void); /* (MISRA C 2004 rule 8.1) *//* GetIdleTaskMemory prototype (linked to static allocation support) */
void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize );/* USER CODE BEGIN GET_IDLE_TASK_MEMORY */
static StaticTask_t xIdleTaskTCBBuffer;
static StackType_t xIdleStack[configMINIMAL_STACK_SIZE];void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize )
{*ppxIdleTaskTCBBuffer = &xIdleTaskTCBBuffer;*ppxIdleTaskStackBuffer = &xIdleStack[0];*pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;/* place for user code */
}
/* USER CODE END GET_IDLE_TASK_MEMORY *//*** @brief FreeRTOS initialization* @param None* @retval None*/
void MX_FREERTOS_Init(void) {/* USER CODE BEGIN Init *//* USER CODE END Init *//* USER CODE BEGIN RTOS_MUTEX *//* add mutexes, ... *//* USER CODE END RTOS_MUTEX *//* USER CODE BEGIN RTOS_SEMAPHORES *//* add semaphores, ... *//* USER CODE END RTOS_SEMAPHORES *//* USER CODE BEGIN RTOS_TIMERS *//* start timers, add new ones, ... *//* USER CODE END RTOS_TIMERS *//* USER CODE BEGIN RTOS_QUEUES *//* add queues, ... *//* USER CODE END RTOS_QUEUES *//* Create the thread(s) *//* definition and creation of TaskSend */osThreadDef(TaskSend, StartTaskSend, osPriorityNormal, 0, 128);TaskSendHandle = osThreadCreate(osThread(TaskSend), NULL);/* definition and creation of TaskReceive */osThreadDef(TaskReceive, StartTaskReceive, osPriorityNormal, 0, 128);TaskReceiveHandle = osThreadCreate(osThread(TaskReceive), NULL);/* USER CODE BEGIN RTOS_THREADS *//* add threads, ... *//* USER CODE END RTOS_THREADS */}/* USER CODE BEGIN Header_StartTaskSend */
/*** @brief Function implementing the TaskSend thread.* @param argument: Not used* @retval None*/
/* USER CODE END Header_StartTaskSend */
void StartTaskSend(void const * argument)
{/* USER CODE BEGIN StartTaskSend */static uint32_t cnt = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){if(cnt == 0){xTaskNotify(TaskReceiveHandle ,1 ,eSetValueWithOverwrite); /*覆盖*/cnt++;printf("任务通知模拟邮箱(长度为1的队列)写入值:1\r\n");}else{xTaskNotify(TaskReceiveHandle ,5 ,eSetValueWithOverwrite);printf("任务通知模拟邮箱(长度为1的队列)写入值:5\r\n");cnt = 0;}}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskSend */
}/* USER CODE BEGIN Header_StartTaskReceive */
/**
* @brief Function implementing the TaskReceive thread.
* @param argument: Not used
* @retval None
*/
/* USER CODE END Header_StartTaskReceive */
void StartTaskReceive(void const * argument)
{/* USER CODE BEGIN StartTaskReceive */uint32_t notify_queue = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){xTaskNotifyWait(0 ,0xFFFFFF ,¬ify_queue ,portMAX_DELAY);printf("任务通知模拟邮箱接收值为:%d\r\n",notify_queue);}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskReceive */
}/* Private application code --------------------------------------------------*/
/* USER CODE BEGIN Application *//* USER CODE END Application */
结果:
5.4.2、不覆盖
/* USER CODE BEGIN Header */
/********************************************************************************* File Name : freertos.c* Description : Code for freertos applications******************************************************************************* @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 "FreeRTOS.h"
#include "task.h"
#include "main.h"
#include "cmsis_os.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 Variables *//* USER CODE END Variables */
osThreadId TaskSendHandle;
osThreadId TaskReceiveHandle;/* Private function prototypes -----------------------------------------------*/
/* USER CODE BEGIN FunctionPrototypes *//* USER CODE END FunctionPrototypes */void StartTaskSend(void const * argument);
void StartTaskReceive(void const * argument);void MX_FREERTOS_Init(void); /* (MISRA C 2004 rule 8.1) *//* GetIdleTaskMemory prototype (linked to static allocation support) */
void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize );/* USER CODE BEGIN GET_IDLE_TASK_MEMORY */
static StaticTask_t xIdleTaskTCBBuffer;
static StackType_t xIdleStack[configMINIMAL_STACK_SIZE];void vApplicationGetIdleTaskMemory( StaticTask_t **ppxIdleTaskTCBBuffer, StackType_t **ppxIdleTaskStackBuffer, uint32_t *pulIdleTaskStackSize )
{*ppxIdleTaskTCBBuffer = &xIdleTaskTCBBuffer;*ppxIdleTaskStackBuffer = &xIdleStack[0];*pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;/* place for user code */
}
/* USER CODE END GET_IDLE_TASK_MEMORY *//*** @brief FreeRTOS initialization* @param None* @retval None*/
void MX_FREERTOS_Init(void) {/* USER CODE BEGIN Init *//* USER CODE END Init *//* USER CODE BEGIN RTOS_MUTEX *//* add mutexes, ... *//* USER CODE END RTOS_MUTEX *//* USER CODE BEGIN RTOS_SEMAPHORES *//* add semaphores, ... *//* USER CODE END RTOS_SEMAPHORES *//* USER CODE BEGIN RTOS_TIMERS *//* start timers, add new ones, ... *//* USER CODE END RTOS_TIMERS *//* USER CODE BEGIN RTOS_QUEUES *//* add queues, ... *//* USER CODE END RTOS_QUEUES *//* Create the thread(s) *//* definition and creation of TaskSend */osThreadDef(TaskSend, StartTaskSend, osPriorityNormal, 0, 128);TaskSendHandle = osThreadCreate(osThread(TaskSend), NULL);/* definition and creation of TaskReceive */osThreadDef(TaskReceive, StartTaskReceive, osPriorityNormal, 0, 128);TaskReceiveHandle = osThreadCreate(osThread(TaskReceive), NULL);/* USER CODE BEGIN RTOS_THREADS *//* add threads, ... *//* USER CODE END RTOS_THREADS */}/* USER CODE BEGIN Header_StartTaskSend */
/*** @brief Function implementing the TaskSend thread.* @param argument: Not used* @retval None*/
/* USER CODE END Header_StartTaskSend */
void StartTaskSend(void const * argument)
{/* USER CODE BEGIN StartTaskSend */static uint32_t cnt = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET){if(cnt == 0){xTaskNotify(TaskReceiveHandle ,1 ,eSetValueWithoutOverwrite); /*不覆盖*/cnt++;printf("任务通知模拟邮箱(长度为1的队列)写入值:1\r\n");}else{xTaskNotify(TaskReceiveHandle ,5 ,eSetValueWithoutOverwrite);printf("任务通知模拟邮箱(长度为1的队列)写入值:5\r\n");cnt = 0;}}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_0) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskSend */
}/* USER CODE BEGIN Header_StartTaskReceive */
/**
* @brief Function implementing the TaskReceive thread.
* @param argument: Not used
* @retval None
*/
/* USER CODE END Header_StartTaskReceive */
void StartTaskReceive(void const * argument)
{/* USER CODE BEGIN StartTaskReceive */uint32_t notify_queue = 0;/* Infinite loop */for(;;){if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){osDelay(20);if(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET){xTaskNotifyWait(0 ,0xFFFFFF ,¬ify_queue ,portMAX_DELAY);printf("任务通知模拟邮箱接收值为:%d\r\n",notify_queue);}while(HAL_GPIO_ReadPin(GPIOA ,GPIO_PIN_1) == GPIO_PIN_RESET);}osDelay(10);}/* USER CODE END StartTaskReceive */
}/* Private application code --------------------------------------------------*/
/* USER CODE BEGIN Application *//* USER CODE END Application */
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