基于STM32 HAL 单IO口设计实现支持DS18B20多设备的热插拔（皆可应用在毕设/课设/大作业/实训/竞赛/项目开发）

Documentation and download available at http://www.FreeRTOS.org/ Changes between FreeRTOS V10.3.0 and FreeRTOS V10.3.1 released February 18 2020 See http://www.FreeRTOS.org/FreeRTOS-V10.3.x.html ./FreeRTOS-Labs directory was removed from this file. The libraries it contained are now available as a separate download. Changes between FreeRTOS V10.2.1 and FreeRTOS V10.3.0 released February 7 2020 See http://www.FreeRTOS.org/FreeRTOS-V10.3.x.html New and updated kernel ports: + Added RISC-V port for the IAR compiler. + Update the Windows simulator port to use a synchronous object to prevent a user reported error whereby a task continues to run for a short time after being moved to the Blocked state. Note we were not able to replicate the reported issue and it likely depends on your CPU model. + Correct alignment of stack top in RISC-V port when configISR_STACK_SIZE_WORDS is defined to a non zero value, which causes the interrupt stack to be statically allocated. + The RISC-V machine timer compare register can now be for any HART, whereas previously it was always assumed FreeRTOS was running on HART 0. + Update the sequence used to update the 64-bit machine timer compare register on 32-bit cores to match that suggested in RISC-V documentation. + Added tickless low power modes into the ARM, IAR and GCC Cortex-M0 compiler ports. + Updated the behaviour of the ARMv7-M MPU (Memory Protection Unit) ports to match that of the ARMv8-M ports whereby privilege escalations can only originate from within the kernel's own memory segment. Added configENFORCE_SYSTEM_CALLS_FROM_KERNEL_ONLY configuration constant. + Update existing MPU ports to correctly disable the MPU before it is updated. + Added contributed port and demo application for a T-Head (formally C-SKY) microcontroller. New API functions: + Added the vPortGetHeapStats() API function which returns information on the heap_4 and heap_5 state. + Added xTaskCatchUpTicks(), which corrects the tick count value after the application code has held interrupts disabled for an extended period. + Added xTaskNotifyValueClear() API function. + Added uxTimerGetReloadMode() API function. Other miscellaneous changes: + Change type of uxPendedTicks from UBaseType_t to TickType_t to ensure it has the same type as variables with which it is compared to, and therefore also renamed the variable xPendingTicks. + Update Keil projects that use the MPU so memory regions come from linker script (scatter file) variables instead of being hard coded. + Added LPC51U68 Cortex-M0+ demos for GCC (MCUXpresso), Keil and IAR compilers. + Added CORTEX_MPU_STM32L4_Discovery_Keil_STM32Cube demo. + Added LPC54018 MPU demo. + Rename xTaskGetIdleRunTimeCounter() to ulTaskGetIdleRunTimeCounter(). Changes between FreeRTOS V10.2.1 and FreeRTOS V10.2.0 released May 13 2019: + Added ARM Cortex-M23 port layer to complement the pre-existing ARM Cortex-M33 port layer. + The RISC-V port now automatically switches between 32-bit and 64-bit cores. + Introduced the portMEMORY_BARRIER macro to prevent instruction re-ordering when GCC link time optimisation is used. + Introduced the portDONT_DISCARD macro to the ARMv8-M ports to try and prevent the secure side builds from removing symbols required by the non secure side build. + Introduced the portARCH_NAME to provide additional data to select semi- automated build environments. + Cortex-M33 and Cortex-M23 ports now correctly disable the MPU before updating the MPU registers. + Added Nuvoton NuMaker-PFM-M2351 ARM Cortex-M23 demo. + Added LPC55S69 ARM Cortex-M33 demo. + Added an STM32 dual core AMP stress test demo. Changes between FreeRTOS V10.1.1 and FreeRTOS V10.2.0 released February 25 2019: + Added GCC RISC-V MCU port with three separate demo applications. + Included pre-existing ARM Cortex-M33 (ARMv8-M) GCC/ARMclang and IAR ports with Keil simulator demo. + Update the method used to detect if a timer is active. Previously the timer was deemed to be inactive if it was not referenced from a list. However, when a timer is updated it is temporarily removed from, then re-added to a list, so now the timer's active status is stored separately. + Add vTimerSetReloadMode(), xTaskGetIdleRunTimeCounter(), and xTaskGetApplicationTaskTagFromISR() API functions. + Updated third party Xtensa port so it is MIT licensed. + Added configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H to the Renesas compiler RX600v2 port to enable switching between platform.h and iodefine.h includes within that port's port.c file. + Removed the 'FromISR' functions from the MPU ports as ISRs run privileged anyway. + Added uxTaskGetStackHighWaterMark2() function to enable the return type to be changed without breaking backward compatibility. uxTaskGetStackHighWaterMark() returns a UBaseType_t as always, uxTaskGetStackHighWaterMark2() returns configSTACK_DEPTH_TYPE to allow the user to determine the return type. + Fixed issues in memory protected ports related to different combinations of static memory only and dynamic memory only builds. As a result the definition of tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE became more complex and was moved to FreeRTOS.h with a table explaining its definition. + Added a 'get task tag from ISR' function. + Change the method used to determine if a timer is active or not from just seeing if it is referenced from the active timer list to storing its active state explicitly. The change prevents the timer reporting that it is inactive while it is being moved from one list to another. + The pcName parameter passed into the task create functions can be NULL, previously a name had to be provided. + When using tickless idle, prvResetNextTaskUnblockTime() is now only called in xTaskRemoveFromEventList() if the scheduler is not suspended. + Introduced portHAS_STACK_OVERFLOW_CHECKING, which should be set to 1 for FreeRTOS ports that run on architectures that have stack limit registers. Changes between FreeRTOS V10.1.0 and FreeRTOS V10.1.1 released 7 September 2018 + Reverted a few structure name changes that broke several kernel aware debugger plug-ins. + Updated to the latest trace recorder code. + Fixed some formatting in the FreeRTOS+TCP TCP/IP stack code. + Reverted moving some variables from file to function scope as doing so broke debug scenarios that require the static qualifier to be removed. Changes between FreeRTOS V10.0.1 and FreeRTOS V10.1.0 released 22 August 2018 FreeRTOS Kernel Changes: + Update lint checked MISRA compliance to use the latest MISRA standard, was previously using the original MISRA standard. + Updated all object handles (TaskHandle_t, QueueHandle_t, etc.) to be unique types instead of void pointers, improving type safety. (this was attempted some years back but had to be backed out due to bugs in some debuggers). Note this required the pvContainer member of a ListItem_t struct to be renamed - set configENABLE_BACKWARD_COMPATIBILITY to 1 if this causes an issue. + Added configUSE_POSIX_ERRNO to enable per task POSIX style errno functionality in a more user friendly way - previously the generic thread local storage feature was used for this purpose. + Added Xtensa port and demo application for the XCC compiler. + Changed the implementation of vPortEndScheduler() for the Win32 port to simply call exit( 0 ). + Bug fix in vPortEnableInterrupt() for the GCC Microblaze port to protect the read modify write access to an internal Microblaze register. + Fix minor niggles when the MPU is used with regards to prototype differences, static struct size differences, etc. + The usStackHighWaterMark member of the TaskStatus_t structure now has type configSTACK_DEPTH_TYPE in place of uint16_t - that change should have been made when the config