第七講：嵌入式實(shí)時(shí)操作系統(tǒng)FreeRTOS

21天學(xué)嵌入式開(kāi)發(fā)第七講：嵌入式實(shí)時(shí)操作系統(tǒng)FreeRTOS

課程安排嵌入式實(shí)時(shí)操作系統(tǒng)FreeRTOS簡(jiǎn)介

嵌入式操作系統(tǒng)基本概念

FreeRTOS的API模塊嵌入式實(shí)時(shí)操作系統(tǒng)FreeRTOS簡(jiǎn)介FreeRTOS是一個(gè)可移植的、開(kāi)源的小型實(shí)時(shí)內(nèi)核。FreeRTOS支持的處理器架構(gòu)有如下幾種：

ARM7,ARM9,Cortex-M3AtmelAVR32AtmelAVRMicrochipPICMicroPIC18,PIC24,dsPICandPIC32MSP430ColdFireHCS12NEC16and32bitprocessorsXilinxVirtex4FPGA嵌入式實(shí)時(shí)操作系統(tǒng)FreeRTOS簡(jiǎn)介FreeRTOS的主要功能：優(yōu)先級(jí)調(diào)度、相同優(yōu)先級(jí)任務(wù)的輪轉(zhuǎn)調(diào)度，同時(shí)可設(shè)成可剝奪內(nèi)核或不可剝奪內(nèi)核任務(wù)可選擇是否共享堆棧，并且沒(méi)有任務(wù)數(shù)限制消息隊(duì)列，二值信號(hào)量，計(jì)數(shù)信號(hào)量，遞歸互斥體時(shí)間管理內(nèi)存管理

嵌入式操作系統(tǒng)基本概念

多任務(wù)

調(diào)度

上下文切換

實(shí)時(shí)應(yīng)用和調(diào)度

FreeRTOS的API模塊定制

FreeRTOSConfig.h

#ifndefFREERTOS_CONFIG_H#defineFREERTOS_CONFIG_H#include"something.h"#defineconfigUSE_PREEMPTION1#defineconfigUSE_IDLE_HOOK0#defineconfigUSE_TICK_HOOK0#defineconfigCPU_CLOCK_HZ58982400#defineconfigTICK_RATE_HZ250#defineconfigMAX_PRIORITIES5#defineconfigMINIMAL_STACK_SIZE128#defineconfigTOTAL_HEAP_SIZE10240#defineconfigMAX_TASK_NAME_LEN16#defineconfigUSE_TRACE_FACILITY0#defineconfigUSE_16_BIT_TICKS0#defineconfigIDLE_SHOULD_YIELD1#defineconfigUSE_MUTEXES0#defineconfigUSE_RECURSIVE_MUTEXES0#defineconfigUSE_COUNTING_SEMAPHORES0#defineconfigUSE_ALTERNATIVE_API0#defineconfigCHECK_FOR_STACK_OVERFLOW0#defineconfigQUEUE_REGISTRY_SIZE10#defineINCLUDE_vTaskPrioritySet1#defineINCLUDE_uxTaskPriorityGet1#defineINCLUDE_vTaskDelete1#defineINCLUDE_vTaskCleanUpResources0#defineINCLUDE_vTaskSuspend1#defineINCLUDE_vResumeFromISR1#defineINCLUDE_vTaskDelayUntil1#defineINCLUDE_vTaskDelay1#defineINCLUDE_xTaskGetSchedulerState1#defineINCLUDE_xTaskGetCurrentTaskHandle1#defineINCLUDE_uxTaskGetStackHighWaterMark0#defineconfigUSE_CO_ROUTINES0#defineconfigMAX_CO_ROUTINE_PRIORITIES1#defineconfigKERNEL_INTERRUPT_PRIORITY [dependentofprocessor]#defineconfigMAX_SYSCALL_INTERRUPT_PRIORITY [dependentonprocessor andapplication]#endif/*FREERTOS_CONFIG_H*/FreeRTOS的API模塊任務(wù)創(chuàng)建和刪除

portBASE_TYPExTaskCreate(pdTASK_CODEpvTaskCode,constportCHAR*constpcName,unsignedportSHORTusStackDepth,void*pvParameters,unsignedportBASE_TYPEuxPriority,xTaskHandle*pvCreatedTask);FreeRTOS的API模塊任務(wù)控制vTaskDelay

vTaskDelayUntil

uxTaskPriorityGet

vTaskPrioritySet

vTaskSuspend

vTaskResume

vTaskResumeFromISR

vTaskSetApplicationTag

vxTaskCal