1 Documentation and download available at https://www.FreeRTOS.org/
3 Changes between FreeRTOS V11.1.0 and FreeRTOS V11.2.0 released March 04, 2025
5 + Add CC-RH port for Renesas F1Kx devices. We thank @TrongNguyenR for their
7 + Add Pointer Authentication (PAC) and Branch Target Identification (BTI)
8 support to the ARMv8-M ports. We thank @AhmedIsmail02 for their
10 + Add Floating Point Unit (FPU) support to the ARM_AARCH64 port. We thank
11 @StefanBalt for their contribution.
12 + Add FPU Safe Application IRQ Handler suport to the ARM_AARCH64_SRE port.
13 We thank @GhMarwen for their contribution.
14 + Add Privileged eXecute Never MPU attribute support to the ARMv8-M ports.
15 We thank @AhmedIsmail02 for their contribution.
16 + Update XMOS xcore.ai port to be compatible with FreeRTOS Kernel version
17 11. We thank @ACascarino for their contribution.
18 + ARM_CRx_No_GIC port updates:
19 - Remove inline assembly and move assembly code to separate portASM.S
21 - Add support for Floating Point Unit (FPU).
22 - Add support to allow the application writer to handle SVC calls raised
23 from the application code.
24 - Add support for vApplicationFPUSafeIRQHandler.
26 - Set PTHREAD_MUTEX_ROBUST attribute on the mutex to prevent application
27 hangs when a thread dies while holding a mutex.
28 - Avoid calling pthread_sigmask on non-FreeROS threads when
29 vPortEndScheduler is called from a non-FreeRTOS thread. We thank
30 @johnboiles for their contribution.
31 - Remove unnecessary call to pthread_attr_setstacksize. We thank
32 @hollinsky for their contribution.
33 - Add an assert to catch if vPortYield is called from a non-FreeRTOS
34 thread. We thank @johnboiles for their contribution.
35 - Fix Posix port compilation on FreeBSD. We thank @tymmej for their
37 + Update the Xtensa port and move it to the Partner-Supported-Ports
38 repository. We thank @ianstcdns for their contribution.
39 + Add vPortGenerateSimulatedInterruptFromWindowsThread API in the MSVC-MingW
40 port to enable native windows thread to synchronize with FreeRTOS task
41 through simulated interrupt.
42 + Update Windows port to use Waitable Timer instead of Sleep to improve tick
43 accuracy. We thank @bknicholls and @leegeth for their contribution.
44 + Update the value of queueQUEUE_TYPE_SET to a unique value (5) to allow
45 tracers to differentiate between queues and queue sets. We thank @schilkp
46 for their contribution.
47 + Add traceSTARTING_SCHEDULER tracing hook to enable tracers to run code on
48 startup. We thank @schilkp for their contribution.
49 + Define vApplicationGetTimerTaskMemory only when configUSE_TIMERS is set to
50 1. We thank @HazardyKnusperkeks for their contribution.
51 + Reset xNextTaskUnblockTime in task notify FromISR APIs to allow the core
52 to enter sleep mode at the earliest possible time when using tickless
54 + Optimize xTaskIncrementTick for SMP by removing xYieldRequiredForCore. We
55 thank @cymizer for their contribution.
56 + Update the SMP scheduler to re-select a core to yield when the core
57 affinity of a ready task is changed.
58 + Update xEventGroupSetBits to read the event bits value to be returned to
59 the caller while the scheduler is suspended. This fixes dereference after
60 the event group is deleted by higher priority task. We thank @skotopes for
62 + Optimize certain getter APIs by removing unnecessary calls to
63 task{ENTER|EXIT}_CRITICAL() when the data access is atomic. We thank
64 @GuilhermeGiacomoSimoes for their contribution.
65 + Optimize xTaskNotifyWait and ulTaskNotifyTake APIs to suspend the
66 scheduler only if the task is not already notified, and the caller is
67 willing to wait for the notification. We thank @jefftenney for
69 + Fix error checking of prvCreateIdleTasks. We thank @kakkoko for their
71 + Update SMP lock macros and critical nesting macros to pass core ID as an
72 argument. This reduces the number of accesses to a peripheral register to
73 query core ID. We thank @felixvanoost for their contribution.
74 + Add stack pointer bounds check when configCHECK_FOR_STACK_OVERFLOW is set
75 to 2 to improve reliability of stack overflow detection. We thank
76 @jiladahe1997 for their contribution.
77 + Update run-time stats to include time elapsed since the last context
78 switch for the currently running task.
79 + Add xQueueCreateSetStatic API for static creation of Queue Sets. We thank
80 @kzorer for their contribution.
81 + Update the traceMALLOC() macro to pass the actual size of the allocated
82 block for secure_heap, heap_2, heap_4 and heap_5. We thank @DazzlingOkami
83 for their contribution.
84 + Update heap_1 to use heapADD_WILL_OVERFLOW macro to improve readability.
85 We thank @wdfk-prog for their contribution.
86 + Add pointer protection to the pxNextFreeBlock member of the allocated
87 block's metadata in heap_4 and heap_5 when configENABLE_HEAP_PROTECTOR is
88 set to 1. We thank @Saiiijchan for their contribution.
89 + Allow the application writer to override pointer validation for heap_5
90 when configENABLE_HEAP_PROTECTOR is used. We thank @Saiiijchan for their
92 + Add xPortResetHeapMinimumEverFreeHeapSize to heap_4.c and heap_5.c.
93 We thank @TomasGalbickaNXP for their contribution.
94 + Add NULL check in the event_create function in the POSIX port. We thank
95 @laroche for their contribution.
96 + Use _GNU_SOURCE macro instead of __USE_GNU in the Posix port. We thank
97 @maxiaogood for their contribution.
98 + Use the new __ARM_FP macro instead of the deprectred __VFP_FP__ macro in
99 GCC/ARM_CM7, GCC/ARM_CM4_MPU, and GCC/ARM_CM4F ports. We thank @haydenridd
100 for their contribution.
101 + Add portMEMORY_BARRIER definition to the Xtensa port. We thank @superroc
102 for their contribution.
103 + Move the hardware include msp430.h to port.c from portmacro.h. We thank
104 @mayl for their contribution.
105 + Update ARM assembly syntax for Cortex-M ports. We thank @laroche for their
107 + Update the Windows port to records a pending yield in
108 vPortCloseRunningThread to ensure that the next tick interrupt schedules
109 the next task regardless of the value of configUSE_PREEMPTION.
110 + Fix the context switch issue in the RL78 port. We thank @KeitaKashima for
112 + Fix compilation issue in ARM CM0 port when using Keil MDK. We thank
113 @TomasGalbickaNXP for their contribution.
114 + Fix IA32 port compilation when configUSE_COMMON_INTERRUPT_ENTRY_POINT is
115 set to 0. We thank @Ryzee119 for their contribution.
116 + Store configMTIMECMP_BASE_ADDRESS in a 64-bit integer for the RISC-V port.
117 We thank @vishwamartur for their contribution.
118 + Fix nested interrupt handling and optimize FPU related context switching
119 for the F1Kx port. We thank @TrongNguyenR for their contribution.
120 + Update the RP2040 port to add support for Raspberry Pi Pico SDK 2.0.0.
121 We thank @kilograham for their contribution.
122 + Fix the return value of portYIELD_FROM_ISR macro for the MSVC-MingW port.
123 We thank @wwhheerree for their contribution.
124 + Optimize vApplicationFPUSafeIRQHandler for the Coretex-A9 port by
125 removing the unnecessarily preserved callee saved registers. We thank
126 @Saiiijchan for their contribution.
127 + Fix the context array size for MPU ports to ensure the saved context
128 location falls within the reserved context area rather than overlapping
129 with the next MPU_SETTINGS structure member.
130 + Update CMake files for RP2040 port to fetch the port from the
131 Community-Supported-Ports repo. We thank @kilograham for their
133 + Fix CMake file for the GCC ARM_CM0 port to include MPU files. We thank
134 @0mhu for their contribution.
135 + Add an example of human readable table generated by vTaskListTasks() in
136 the function documentation. We thank @wwhheerree for their contribution.
138 Changes between FreeRTOS V11.0.1 and FreeRTOS V11.1.0 released April 22, 2024
140 + Add ARMv7-R port with Memory Protection Unit (MPU) support.
141 + Add Memory Protection Unit (MPU) support to the Cortex-M0 port.
142 + Add stream batching buffer. A stream batching buffer differs from a stream
143 buffer when a task reads from a non-empty buffer:
144 - The task reading from a non-empty stream buffer returns immediately
145 regardless of the amount of data in the buffer.
146 - The task reading from a non-empty steam batching buffer blocks until the
147 amount of data in the buffer exceeds the trigger level or the block time
149 We thank @cperkulator for their contribution.
150 + Add the ability to change task notification index for stream buffers. We
151 thank @glemco for their contribution.
152 + Add xStreamBufferResetFromISR and xMessageBufferResetFromISR APIs to reset
153 stream buffer and message buffer from an Interrupt Service Routine (ISR).
154 We thank @HagaiMoshe for their contribution.
155 + Update all the FreeRTOS APIs to use configSTACK_DEPTH_TYPE for stack type.
156 We thank @feilipu for their contribution.
157 + Update vTaskEndScheduler to delete the timer and idle tasks,
158 once the scheduler is stopped.
159 + Make xTaskGetCurrentTaskHandleForCore() available to the single core
160 scheduler. We thank @Dazza0 for their contribution.
161 + Update uxTaskGetSystemState to not use the pxIndex member of the List_t
162 structure while iterating ready tasks list. The reason is that pxIndex
163 member must only used to select next ready task to run. We thank
164 @gemarcano for their inputs.
165 + Add a config option to the FreeRTOS SMP Kernel to set the default core
166 affinity mask for tasks created without an affinity mask. We thank @go2sh
167 for their contribution.
168 + Add configUSE_EVENT_GROUPS and configUSE_STREAM_BUFFERS configuration
169 constants to control the inclusion of event group and stream buffer
171 + Code changes to comply with MISRA C 2012.
172 + Add 64-bit support to the FreeRTOS Windows Simulator port. We thank @watsk
173 and @josesimoes for their contributions.
174 + Add support for 64-bit Microblaze processor to the MicroblazeV9 port. We
175 thank @mubinsyed for their contribution.
176 + Add support for MSP430 Embedded Application Binary Interface (EABI) to
177 the MSP430F449 port to make it work with both MSP430 GCC and MSPGCC
178 compilers. We thank @Forty-Bot for their contribution.
179 + Update xPortIsAuthorizedToAccessBuffer() on FreeRTOS ports with MPU
180 support to grant an unprivileged task access to all the memory before the
181 scheduler is started.
182 + Update the POSIX port to pass the FreeRTOS task name to pthread for
183 readable output in debuggers. We thank @Mixaill for their contribution.
184 + Update the POSIX port to ignore the user specified stack memory and only
185 pass the stack size to the pthread API to avoid errors caused when stack size
186 is smaller than the minimum. We thank @cmorgnaBE for their
188 + Update the POSIX port to use a timer thread for tick interrupts instead of
189 POSIX timers to address issues with signal handling in non-FreeRTOS
190 pthreads. We thank @cmorgnaBE for their contribution.
191 + Update ARM_TFM port to support TF-Mv2.0.0 release of trusted-firmware-m.
192 We thanks @urutva for their contribution.
193 + Remove redundant constant pools in ARMv8 ports. We thank @urutva for their
195 + Add APIs to reset the internal state of kernel modules. These APIs are
196 primarily intended to be used in the testing frameworks that restart the
198 + Use kernel provided implementations of vApplicationGetIdleTaskMemory() and
199 vApplicationGetTimerTaskMemory() in the RP2040 port. We thank @dpslwk for
201 + Fix atomic enter/exit critical section macro definitions in atomic.h for
202 ports that support nested interrupts. We thank @sebunger for their
204 + Fix compiler warnings in the MSP430F449 port when compiled with the
205 MSP430 GCC compiler. We thank @Forty-Bot for their contribution.
206 + Update the scheduler suspension usage in ulTaskGenericNotifyTake and
207 xTaskGenericNotifyWait() to enhance code readability. We thank @Dazza0 for
209 + Add support for latest version of MPU wrappers( mpu_wrappers_v2) in CMake.
210 We thank @IsaacDynamo for their contribution.
211 + Update CMake support to create only one static library containing both the
212 kernel common code and the kernel port code. We thank @barnatahmed for
215 Changes between FreeRTOS V11.0.0 and FreeRTOS V11.0.1 released December 21, 2023
217 + Updated the SBOM file.
219 Changes between FreeRTOS V10.6.2 and FreeRTOS V11.0.0 released December 18, 2023
221 + SMP merged into the mainline: While FreeRTOS introduced Asymmetric
222 Multiprocessing (AMP) support in 2017, FreeRTOS Version 11.0.0 is the
223 first to merge Symmetric Multiprocessing (SMP) support into the mainline
224 release. SMP enables one instance of the FreeRTOS Kernel to schedule tasks
225 across multiple identical processor cores. We thank Mike Bruno and Jerry
226 McCarthy of XMOS and, Darian Liang, Sudeep Mohanty and Zim Kalinowski of
227 Espressif Systems for their contributions.
228 + Switch MISRA compliance checking from PC Lint to Coverity, and update from
229 MISRA C:2004 to MISRA C:2012.
230 + Add a template FreeRTOSConfig.h, inclusive of an abbreviated explanation of
231 each configuration item. Application writers can use this template as a
232 starting point to create the FreeRTOSConfig.h file for their application.
233 + Add a template FreeRTOS port which can be used as a starting point for
234 developing a new FreeRTOS port.
235 + Add bounds checking and obfuscation to internal heap block pointers in
236 heap_4.c and heap_5.c to help catch pointer corruptions. The application can
237 enable these checks by setting configENABLE_HEAP_PROTECTOR to 1 in their
238 FreeRTOSConfig.h. We thank @oliverlavery for their contribution.
239 + Update vTaskList and vTaskGetRunTimeStats APIs to replace the use of sprintf
241 + Add trace macros to ports that enable tracing the interaction of ISRs with
242 scheduler events. We thank @conara for their contribution.
243 + Add trace macros that enable tracing of entering and exiting all APIs. We
244 thank @Techcore123 for their contribution.
245 + Add uxTaskBasePriorityGet and uxTaskBasePriorityGetFromISR APIs to get the
246 base priority of a task. The base priority of a task is the priority that
247 was last assigned to the task - which due to priority inheritance, may not
248 be the current priority of the task.
249 + Add pdTICKS_TO_MS macro to convert time in FreeRTOS ticks to time in
250 milliseconds. We thank @Dazza0 for their contribution.
251 + Add default implementations of vApplicationGetIdleTaskMemory and
252 vApplicationGetTimerTaskMemory. The application can enable these default
253 implementations by setting configKERNEL_PROVIDED_STATIC_MEMORY to 1 in their
254 FreeRTOSConfig.h. We thank @mdnr-g for their contribution.
255 + Update vTaskGetInfo to include start and end of the stack whenever both
256 values are available. We thank @vinceburns for their contribution.
257 + Prevent tasks waiting for a notification from being resumed by calls to
258 vTaskResume or vTaskResumeFromISR. We thank @Moral-Hao for their
260 + Add asserts to validate that the application has correctly installed
261 FreeRTOS handlers for PendSV and SVCall interrupts on Cortex-M devices.
262 We thank @jefftenney for their contribution.
263 + Rename ARM_CA53_64_BIT and ARM_CA53_64_BIT_SRE ports to Arm_AARCH64 and
264 Arm_AARCH64_SRE respectively as these ports are applicable to all AArch64
265 architecture. We thank @urutva for their contribution.
266 + Add CMake support to allow the application writer to select the RISC-V
267 chip extension. We thank @JoeBenczarski for their contribution.
268 + Add CMake support to allow the application writer to build an application
269 with static allocation only. We thank @conara for their contribution.
270 + Make taskYIELD available to unprivileged tasks for ARMv8-M ports.
271 + Update Cortex-M23 ports to not use PSPLIM_NS. We thank @urutva for their
273 + Update the SysTick setup code for ARMv8-M ports to first configure the clock
274 source and then enable SysTick. This is needed to address a bug in QEMU
275 versions older than 7.0.0, which causes an emulation error if SysTick is
276 enabled without first selecting a valid clock source. We thank @jefftenney
277 for their contribution.
278 + Add the port-optimized task selection algorithm optionally available for
279 ARMv7-M ports to the ARMv8-M ports. We thank @jefftenney for their
281 + Improve the speed of pvPortMalloc in heap_4.c and heap_5.c by removing
282 unnecessary steps while splitting a large memory block into two. We thank
283 @Moral-Hao for their contribution.
284 + Shorten the critical section in pvPortMalloc in heap_2.c, heap_4.c and
285 heap_5.c by moving the size calculation out of the critical section. We thank
286 @Moral-Hao for their contribution.
287 + Update xTaskNotifyWait and ulTaskNotifyTake to remove the non-deterministic
288 operation of traversing a linked link from a critical section. We thank
289 @karver8 for their contribution.
290 + Fix stack end and stack size computation in POSIX port to meet the stack
291 alignment requirements on MacOS. We thank @tegimeki for their contribution.
292 + Update the vTaskPrioritySet implementation to use the new priority when the
293 task has inherited priority from a mutex it is holding, and the new priority
294 is bigger than the inherited priority. We thank @Moral-Hao for their
296 + Add stack alignment adjustment if stack grows upwards. We thank @ivq for
298 + Fix pxTopOfStack calculation in configINIT_TLS_BLOCK when picolib C is
299 selected as the C library implementation to ensure that
300 pxPortInitialiseStack does not overwrite the data in the TLS block portion
301 of the stack. We thank @bebebib-rs for their contribution.
302 + Fix vPortEndScheduler() for the MSVC port so that the function
303 prvProcessSimulatedInterrupts is not stuck in an infinite loop when the
304 scheduler is stopped. We thank @Ju1He1 for their contribution.
305 + Add the Pull Request (PR) Process explaining the stages a PR goes through.
307 Changes between FreeRTOS V10.6.1 and FreeRTOS V10.6.2 released November 29, 2023
309 + Add the following improvements to the new MPU wrapper (mpu_wrappers_v2.c)
310 introduced in version 10.6.0:
311 - Introduce Access Control List (ACL) feature to allow the application
312 writer to control an unprivileged task’s access to kernel objects.
313 - Update the system call entry mechanism to only require one Supervisor
314 Call (SVC) instruction.
315 - Wrap parameters for system calls with more than four parameters in a
316 struct to avoid special handling during system call entry.
317 - Fix 2 possible integer overflows.
318 - Convert some asserts to run time parameter checks.
320 Changes between FreeRTOS V10.6.0 and FreeRTOS V10.6.1 released August 17, 2023
322 + Add runtime parameter checks to functions in mpu_wrappers_v2.c file.
323 The same checks are already performed in API implementations using
325 We thank the following people for their inputs in these changes:
326 - Lan Luo, Zixia Liu of School of Computer Science and Technology,
327 Anhui University of Technology, China.
328 - Xinwen Fu of Department of Computer Science, University of
329 Massachusetts Lowell, USA.
330 - Xinhui Shao, Yumeng Wei, Huaiyu Yan, Zhen Ling of School of
331 Computer Science and Engineering, Southeast University, China.
333 Changes between FreeRTOS V10.5.1 and FreeRTOS 10.6.0 released July 13, 2023
335 + Add a new MPU wrapper that places additional restrictions on unprivileged
336 tasks. The following is the list of changes introduced with the new MPU
339 1. Opaque and indirectly verifiable integers for kernel object handles:
340 All the kernel object handles (for example, queue handles) are now
341 opaque integers. Previously object handles were raw pointers.
342 2. Save the task context in Task Control Block (TCB): When a task is
343 swapped out by the scheduler, the task's context is now saved in its
344 TCB. Previously the task's context was saved on its stack.
345 3. Execute system calls on a separate privileged only stack: FreeRTOS
346 system calls, which execute with elevated privilege, now use a
347 separate privileged only stack. Previously system calls used the
348 calling task's stack. The application writer can control the size of
349 the system call stack using new configSYSTEM_CALL_STACK_SIZE config
351 4. Memory bounds checks: FreeRTOS system calls which accept a pointer
352 and de-reference it, now verify that the calling task has required
353 permissions to access the memory location referenced by the pointer.
354 5. System calls restrictions: The following system calls are no longer
355 available to unprivileged tasks:
358 - xQueueCreateMutexStatic
359 - xQueueCreateCountingSemaphore
360 - xQueueCreateCountingSemaphoreStatic
361 - xQueueGenericCreate
362 - xQueueGenericCreateStatic
364 - xQueueRemoveFromSet
373 - xTaskCallApplicationTaskHook
375 - vTaskGetRunTimeStats
378 - xEventGroupCreateStatic
380 - xStreamBufferGenericCreate
381 - xStreamBufferGenericCreateStatic
382 - vStreamBufferDelete
384 Also, an unprivileged task can no longer use vTaskSuspend to suspend
385 any task other than itself.
387 We thank the following people for their inputs in these enhancements:
388 - David Reiss of Meta Platforms, Inc.
389 - Lan Luo, Xinhui Shao, Yumeng Wei, Zixia Liu, Huaiyu Yan and Zhen Ling
390 of School of Computer Science and Engineering, Southeast University,
392 - Xinwen Fu of Department of Computer Science, University of
393 Massachusetts Lowell, USA.
394 - Yueqi Chen, Zicheng Wang, Minghao Lin, Jiahe Wang of University of
395 Colorado Boulder, USA.
396 + Add Cortex-M35P port. Contributed by @urutva.
397 + Add embedded extension (RV32E) support to the IAR RISC-V port.
398 + Add ulTaskGetRunTimeCounter and ulTaskGetRunTimePercent APIs. Contributed by
400 + Add APIs to get the application supplied buffers from statically
401 created kernel objects. The following new APIs are added:
402 - xTaskGetStaticBuffers
403 - xQueueGetStaticBuffers
404 - xQueueGenericGetStaticBuffers
405 - xSemaphoreGetStaticBuffer
406 - xEventGroupGetStaticBuffer
407 - xStreamBufferGetStaticBuffers
408 - xMessageBufferGetStaticBuffers
409 These APIs enable the application writer to obtain static buffers from
410 the kernel object and free/reuse them at the time of deletion. Earlier
411 the application writer had to maintain the association of static buffers
412 and the kernel object in the application. Contributed by @Dazza0.
413 + Add Thread Local Storage (TLS) support using picolibc function. Contributed
415 + Add configTICK_TYPE_WIDTH_IN_BITS to configure TickType_t data type. As a result,
416 the number of bits in an event group also increases with big data type. Contributed
418 + Update eTaskGetState and uxTaskGetSystemState to return eReady for pending ready
419 tasks. Contributed by @Dazza0.
420 + Update heap_4 and heap_5 to add padding only if the resulting block is not
422 + Fix the scheduler logic in a couple of places to not preempt a task when an
423 equal priority task becomes ready.
424 + Add macros used in FreeRTOS-Plus libraries. Contributed by @Holden.
425 + Fix clang compiler warnings. Contributed by @phelter.
426 + Add assertions to ARMv8-M ports to detect when FreeRTOS APIs are called from
427 interrupts with priority higher than the configMAX_SYSCALL_INTERRUPT_PRIORITY.
428 Contributed by @urutva.
429 + Add xPortIsInsideInterrupt API to ARM_CM0 ports.
430 + Fix build warning in MSP430X port when large data model is used.
431 + Add the ability to use Cortex-R5 port on the parts without FPU.
432 + Fix build warning in heap implementations on PIC24/dsPIC.
433 + Update interrupt priority asserts for Cortex-M ports so that these do not fire
434 on QEMU which does not implement PRIO bits.
435 + Update ARMv7-M ports to ensure that kernel interrupts run at the lowest priority.
436 configKERNEL_INTERRUPT_PRIORITY is now obsolete for ARMv7-M ports and brings
437 these ports inline with the newer ARMv8-M ports. Contributed by @chrisnc.
438 + Fix build issue in POSIX GCC port on Windows Subsystem for Linux (WSL). Contributed
440 + Add portMEMORY_BARRIER to Microblaze port. Contributed by @bbain.
441 + Add portPOINTER_SIZE_TYPE definition for ATmega port. Contributed by @jputcu.
442 + Multiple improvements in the CMake support. Contributed by @phelte and @cookpate.
444 Changes between FreeRTOS V10.5.0 and FreeRTOS V10.5.1 released November 16 2022
445 + Updated the kernel version in manifest and SBOM
447 Changes between FreeRTOS V10.4.6 and FreeRTOS V10.5.0 released September 16 2022
449 + ARMv7-M and ARMv8-M MPU ports: It was possible for a third party that
450 already independently gained the ability to execute injected code to
451 read from or write to arbitrary addresses by passing a negative argument
452 as the xIndex parameter to pvTaskGetThreadLocalStoragePointer() or
453 vTaskSetThreadLocalStoragePointer respectively. A check has been added to
454 ensure that passing a negative argument as the xIndex parameter does not
455 cause arbitrary read or write.
456 We thank Certibit Consulting, LLC for reporting this issue.
457 + ARMv7-M and ARMv8-M MPU ports: It was possible for an unprivileged task
458 to invoke any function with privilege by passing it as a parameter to
459 MPU_xTaskCreate, MPU_xTaskCreateStatic, MPU_xTimerCreate,
460 MPU_xTimerCreateStatic, or MPU_xTimerPendFunctionCall. MPU_xTaskCreate
461 and MPU_xTaskCreateStatic have been updated to only allow creation of
462 unprivileged tasks. MPU_xTimerCreate, MPU_xTimerCreateStatic and
463 MPU_xTimerPendFunctionCall APIs have been removed.
464 We thank Huazhong University of Science and Technology for reporting
466 + ARMv7-M and ARMv8-M MPU ports: It was possible for a third party that
467 already independently gained the ability to execute injected code to
468 achieve further privilege escalation by branching directly inside a
469 FreeRTOS MPU API wrapper function with a manually crafted stack frame.
470 The local stack variable `xRunningPrivileged` has been removed so that
471 a manually crafted stack frame cannot be used for privilege escalation
472 by branching directly inside a FreeRTOS MPU API wrapper.
473 We thank Certibit Consulting, LLC, Huazhong University of Science and
474 Technology and the SecLab team at Northeastern University for reporting
476 + ARMv7-M MPU ports: It was possible to configure overlapping memory
477 protection unit (MPU) regions such that an unprivileged task could access
478 privileged data. The kernel now uses highest numbered MPU regions for
479 kernel protections to prevent such MPU configurations.
480 We thank the SecLab team at Northeastern University for reporting this
482 + Add support for ARM Cortex-M55.
483 + Add support for ARM Cortex-M85. Contributed by @gbrtth.
484 + Add vectored mode interrupt support to the RISC-V port.
485 + Add support for RV32E extension (Embedded Profile) in RISC-V GCC port.
486 Contributed by @Limoto.
488 - Add a check to heap_2 to track if a memory block is allocated to
489 the application or not. The MSB of the size field is used for this
490 purpose. The same check already exists in heap_4 and heap_5. This
491 check prevents double free errors.
492 - Add a new flag configHEAP_CLEAR_MEMORY_ON_FREE to heap_2, heap_4
493 and heap_5. If the flag is set in FreeRTOSConfig.h then memory freed using
494 vPortFree() is automatically cleared to zero.
495 - Add a new API pvPortCalloc to heap_2, heap_4 and heap_5 which has the same
496 signature as the standard library calloc function.
497 - Update the pointer types to portPOINTER_SIZE_TYPE. Contributed by
499 + Add the ability to override send and receive completed callbacks for each
500 instance of a stream buffer or message buffer. Earlier there could be
501 one send and one receive callback for all instances of stream and message
502 buffers. Having separate callbacks per instance allows different message
503 and stream buffers to be used differently - for example, some for inter core
504 communication and others for same core communication.
505 The feature can be controlled by setting the configuration option
506 configUSE_SB_COMPLETED_CALLBACK in FreeRTOSConfig.h. When the option is set to 1,
507 APIs xStreamBufferCreateWithCallback() or xStreamBufferCreateStaticWithCallback()
508 (and likewise APIs for message buffer) can be used to create a stream buffer
509 or message buffer instance with application provided callback overrides. When
510 the option is set to 0, then the default callbacks as defined by
511 sbSEND_COMPLETED() and sbRECEIVE_COMPLETED() macros are invoked. To maintain
512 backwards compatibility, configUSE_SB_COMPLETED_CALLBACK defaults to 0. The
513 functionality is currently not supported for MPU enabled ports.
514 + Generalize the FreeRTOS's Thread Local Storage (TLS) support so that it
515 is not tied to newlib and can be used with other c-runtime libraries also.
516 The default behavior for newlib support is kept same for backward
518 + Add support to build and link FreeRTOS using CMake build system. Contributed
520 + Add support to generate Software Bill of Materials (SBOM) for every release.
521 + Add support for 16 MPU regions to the GCC Cortex-M33 ports.
522 + Add ARM Cortex-M7 r0p0/r0p1 Errata 837070 workaround to ARM CM4 MPU ports.
523 The application writer needs to define configENABLE_ERRATA_837070_WORKAROUND
524 when using CM4 MPU ports on a Cortex-M7 r0p0/r0p1 core.
525 + Add configSYSTICK_CLOCK_HZ to Cortex-M0 ports. This is needed to support
526 the case when the SysTick timer is not clocked from the same source as the CPU.
527 + Add hardware stack protection support to MicroBlazeV9 port. This ensures that
528 the CPU immediately raises Stack Protection Violation exception as soon as any
529 task violates its stack limits. Contributed by @uecasm.
530 + Introduce the configUSE_MINI_LIST_ITEM configuration option. When this
531 option is set to 1, ListItem_t and MiniLitItem_t remain separate types.
532 However, when configUSE_MINI_LIST_ITEM == 0, MiniLitItem_t and ListItem_t
533 are both typedefs of the same struct xLIST_ITEM. This addresses some issues
534 observed when strict-aliasing and link time optimization are enabled.
535 To maintain backwards compatibility, configUSE_MINI_LIST_ITEM defaults to 1.
536 + Simplify prvInitialiseNewTask to memset newly allocated TCB structures
537 to zero, and remove code that set individual structure members to zero.
538 + Add prototype for prvPortYieldFromISR to the POSIX port so that it builds
539 without any warning with -Wmissing-prototypes compiler option.
540 + Add top of stack and end of stack to the task info report obtained using
541 vTaskGetInfo(). Contributed by @shreyasbharath.
542 + Add a cap to the cRxLock and cTxLock members of the queue data structure.
543 These locks count the number items received and sent to the queue while
544 the queue was locked. These are later used to unblock tasks waiting on
545 the queue when the queue is unlocked. This PR caps the values of the
546 cRxLock and cTxLock to the number of tasks in the system because we cannot
547 unblock more tasks than there are in the system. Note that the same assert
548 could still be triggered is the application creates more than 127 tasks.
549 + Changed uxAutoReload parameter in timer functions to xAutoReload. The
550 type is now BaseType_t. This matches the type of pdTRUE and pdFALSE.
551 The new function xTimerGetAutoReload() provides the auto-reload state as
552 a BaseType_t. The legacy function uxTimerGetAutoReload is retained with the
553 original UBaseType_t return value.
554 + Fix support for user implementations of tickless idle that call
555 vTaskStepTick() with xExpectedIdleTime ticks to step. The new code
556 ensures xTickCount reaches xNextTaskUnblockTime inside xTaskIncrementTick()
557 instead of inside vTaskStepTick(). This fixes the typical case where a task
558 wakes up one tick late and a rare case assertion failure when xTickCount\
559 rolls over. Contributed by @jefftenney.
560 + Fix deadlock in event groups when pvPortMalloc and vPortFree functions
561 are protected with a mutex. Contributed by @clemenskresser.
562 + Fix a warning in tasks.c when compiled with -Wduplicated-branches
563 GCC option. Contributed by @pierrenoel-bouteville-act.
564 + Fix compilation error in tasks.c when configSUPPORT_DYNAMIC_ALLOCATION
565 is set to zero. Contributed by @rdpoor.
566 + Fix prvWriteMessageToBuffer() function in stream_buffer.c so that it correctly
567 copies length on big endian platforms too.
568 + Remove the need for INCLUDE_vTaskSuspend to be set to 1
569 when configUSE_TICKLESS_IDLE is enabled. Contributed by @pramithkv.
570 + Update the RL78 IAR port to the latest version of IAR which uses the
571 industry standard ELF format as opposed to earlier UBROF object format.
572 Contributed by @felipe-iar.
573 + Add tick type is atomic flag when tick count is 16-bit to PIC24 port. This
574 allows the PIC24 family of 16 bit processors to read the tick count without
575 a critical section when the tick count is also 16 bits.
576 + Fix offset-out-of-range errors for GCC CM3/CM4 mpu ports when
577 Link Time Optimization is enabled. Contributed by @niniemann.
578 + Remove #error when RISC-V port is compiled on a 64-bit RISC-V platform.
579 Contributed by @cmdrf.
580 + Fix ullPortInterruptNesting alignment in Cortex-A53 port so that it is
581 8-byte aligned. This fixes the unaligned access exception. Contributed
583 + Fix Interrupt Handler Register Function and Exception Process in NiosII
584 Port. Contributed by @ghost.
585 + Change FreeRTOS IRQ Handler for Cortex-A53 SRE port to store and restore
586 interrupt acknowledge register. This ensures that the SRE port behavior
587 matches the Memory Mapped IO port. Contributed by @sviaunxp.
588 + Update the uncrustify config file to match the version of the uncrustify
589 used in the CI Action. Also, pin the version of uncrustify in CI. Contributed
592 Changes between FreeRTOS V10.4.5 and FreeRTOS V10.4.6 released November 12 2021
594 + ARMv7-M and ARMv8-M MPU ports – prevent non-kernel code from calling the
595 internal functions xPortRaisePrivilege and vPortResetPrivilege by changing
597 + Introduce a new config configALLOW_UNPRIVILEGED_CRITICAL_SECTIONS which
598 enables developers to prevent critical sections from unprivileged tasks.
599 It defaults to 1 for backward compatibility. Application should set it to
600 0 to disable critical sections from unprivileged tasks.
602 Changes between FreeRTOS V10.4.4 and FreeRTOS V10.4.5 released September 10 2021
604 See https://www.FreeRTOS.org/FreeRTOS-V10.4.5.html
606 + Introduce configRUN_TIME_COUNTER_TYPE which enables developers to define
607 the type used to hold run time statistic counters. Defaults to uint32_t
608 for backward compatibility. #define configRUN_TIME_COUNTER_TYPE to a type
609 (for example, uint64_t) in FreeRTOSConfig.h to override the default.
610 + Introduce ulTaskGetIdleRunTimePercent() to complement the pre-existing
611 ulTaskGetIdleRunTimeCounter(). Whereas the pre-existing function returns
612 the raw run time counter value, the new function returns the percentage of
613 the entire run time consumed by the idle task. Note the amount of idle
614 time is only a good measure of the slack time in a system if there are no
615 other tasks executing at the idle priority, tickless idle is not used, and
616 configIDLE_SHOULD_YIELD is set to 0.
617 + ARMv8-M secure-side port: Tasks that call secure functions from the
618 non-secure side of an ARMv8-M MCU (ARM Cortex-M23 and Cortex-M33) have two
619 contexts - one on the non-secure side and one on the secure-side. Previous
620 versions of the FreeRTOS ARMv8-M secure-side ports allocated the structures
621 that reference secure-side contexts at run time. Now the structures are
622 allocated statically at compile time. The change necessitates the
623 introduction of the secureconfigMAX_SECURE_CONTEXTS configuration constant,
624 which sets the number of statically allocated secure contexts.
625 secureconfigMAX_SECURE_CONTEXTS defaults to 8 if left undefined.
626 Applications that only use FreeRTOS code on the non-secure side, such as
627 those running third-party code on the secure side, are not affected by
630 Changes between FreeRTOS V10.4.3 and FreeRTOS V10.4.4 released May 28 2021
631 + Minor performance improvements to xTaskIncrementTick() achieved by providing
632 macro versions of uxListRemove() and vListInsertEnd().
633 + Minor refactor of timers.c that obsoletes the need for the
634 tmrCOMMAND_START_DONT_TRACE macro and removes the need for timers.c to
635 post to its own event queue. A consequence of this change is that auto-
636 reload timers that miss their intended next execution time will execute
637 again immediately rather than executing again the next time the command
638 queue is processed. (thanks Jeff Tenney).
639 + Fix a race condition in the message buffer implementation. The
640 underlying cause was that length and data bytes are written and read as
641 two distinct operations, which both modify the size of the buffer. If a
642 context switch occurs after adding or removing the length bytes, but
643 before adding or removing the data bytes, then another task may observe
644 the message buffer in an invalid state.
645 + The xTaskCreate() and xTaskCreateStatic() functions accept a task priority
646 as an input parameter. The priority has always been silently capped to
647 (configMAX_PRIORITIES - 1) should it be set to a value above that priority.
648 Now values above that priority will also trigger a configASSERT() failure.
649 + Replace configASSERT( pcQueueName ) in vQueueAddToRegistry with a NULL
651 + Introduce the configSTACK_ALLOCATION_FROM_SEPARATE_HEAP configuration
652 constant that enables the stack allocated to tasks to come from a heap other
653 than the heap used by other memory allocations. This enables stacks to be
654 placed within special regions, such as fast tightly coupled memory.
655 + If there is an attempt to add the same queue or semaphore handle to the
656 queue registry more than once then prior versions would create two separate
657 entries. Now if this is done the first entry is overwritten rather than
659 + Update the ESP32 port and TF-M (Trusted Firmware M)code to the latest from
660 their respective repositories.
661 + Correct a build error in the POSIX port.
662 + Additional minor formatting updates, including replacing tabs with spaces
664 + Other minor updates include adding additional configASSERT() checks and
665 correcting and improving code comments.
666 + Go look at the smp branch to see the progress towards the Symmetric
667 Multiprocessing Kernel. https://github.com/FreeRTOS/FreeRTOS-Kernel/tree/smp
669 Changes between FreeRTOS V10.4.2 and FreeRTOS V10.4.3 released December 14 2020
671 V10.4.3 is included in the 202012.00 LTS release. Learn more at https:/freertos.org/lts-libraries.html
673 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
675 + Changes to improve robustness and consistency for buffer allocation in
676 the heap, queue and stream buffer.
677 + The following functions can no longer be called from unprivileged code.
678 - xTaskCreateRestricted
679 - xTaskCreateRestrictedStatic
680 - vTaskAllocateMPURegions
683 Changes between FreeRTOS V10.4.1 and FreeRTOS V10.4.2 released November 10 2020
685 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
687 + Fix an issue in the ARMv8-M ports that caused BASEPRI to be masked
688 between the first task starting to execute and that task making
690 + Introduced xTaskDelayUntil(), which is functionally equivalent to
691 vTaskDelayUntil(), with the addition of returning a value to
692 indicating whether or not the function placed the calling task into
693 the Blocked state or not.
694 + Update WolfSSL to 4.5.0 and add the FIPS ready demo.
695 + Add support for ESP IDF 4.2 to ThirdParty Xtensa port.
696 + Re-introduce uxTopUsedPriority to support OpenOCD debugging.
697 + Convert most dependent libraries in FreeRTOS/FreeRTOS to submodules.
698 + Various general maintenance and improvements to MISRA compliance.
701 Changes between FreeRTOS V10.4.0 and FreeRTOS V10.4.1 released September 17 2020
703 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
705 + Fixed an incorrectly named parameter that prevented the
706 ulTaskNotifyTakeIndexed macro compiling, and the name space clash in the
707 test code that prevented this error causing test failures.
710 Changes between FreeRTOS V10.3.1 and FreeRTOS V10.4.0 released September 10 2020
712 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
716 + Task notifications: Prior to FreeRTOS V10.4.0 each created task had a
717 single direct to task notification. From FreeRTOS V10.4.0 each task has
718 an array of notifications. The direct to task notification API has been
719 extended with API functions postfixed with "Indexed" to enable the API to
720 operate on a task notification at any array index. See
721 https://www.freertos.org/RTOS-task-notifications.html for more information.
722 + Kernel ports that support memory protection units (MPUs): The ARMv7-M and
723 ARMv8-M MPU ports now support a privilege access only heap. The ARMv7-M
724 MPU ports now support devices that have 16 MPU regions, have the ability
725 to override default memory attributes for privileged code and data
726 regions, and have the ability to place the FreeRTOS kernel code outside of
727 the Flash memory. The ARMv8-M MPU ports now support tickless idle mode.
728 See https://www.freertos.org/FreeRTOS-MPU-memory-protection-unit.html
729 for more information.
731 Additional noteworthy updates:
733 + Code formatting is now automated to facilitate the increase in
734 collaborative development in Git. The auto-formated code is not identical
735 to the original formatting conventions. Most notably spaces are now used
737 + The prototypes for callback functions (those that start with "Application",
738 such as vApplicationStackOverflowHook()) are now in the FreeRTOS header
739 files, removing the need for application writers to add prototypes into
740 the C files in which they define the functions.
741 + New Renesas RXv3 port layer.
742 + Updates to the Synopsys ARC code, including support for EM and HS cores,
744 + Added new POSIX port layer that allows FreeRTOS to run on Linux hosts in
745 the same way the Windows port layer enables FreeRTOS to run on Windows
747 + Many other minor optimisations and enhancements. For full details
748 see https://github.com/FreeRTOS/FreeRTOS-Kernel/commits/main
751 Changes between FreeRTOS V10.3.0 and FreeRTOS V10.3.1 released February 18 2020
753 See https://www.FreeRTOS.org/FreeRTOS-V10.3.x.html
755 + ./FreeRTOS-Labs directory was removed from this file. The libraries it
756 contained are now available as a separate download.
758 Changes between FreeRTOS V10.2.1 and FreeRTOS V10.3.0 released February 7 2020
760 See https://www.FreeRTOS.org/FreeRTOS-V10.3.x.html
762 New and updated kernel ports:
764 + Added RISC-V port for the IAR compiler.
765 + Update the Windows simulator port to use a synchronous object to prevent
766 a user reported error whereby a task continues to run for a short time
767 after being moved to the Blocked state. Note we were not able to
768 replicate the reported issue and it likely depends on your CPU model.
769 + Correct alignment of stack top in RISC-V port when
770 configISR_STACK_SIZE_WORDS is defined to a non zero value, which causes
771 the interrupt stack to be statically allocated.
772 + The RISC-V machine timer compare register can now be for any HART, whereas
773 previously it was always assumed FreeRTOS was running on HART 0.
774 + Update the sequence used to update the 64-bit machine timer
775 compare register on 32-bit cores to match that suggested in RISC-V
777 + Added tickless low power modes into the ARM, IAR and GCC Cortex-M0 compiler
779 + Updated the behaviour of the ARMv7-M MPU (Memory Protection Unit) ports to
780 match that of the ARMv8-M ports whereby privilege escalations can only
781 originate from within the kernel's own memory segment. Added
782 configENFORCE_SYSTEM_CALLS_FROM_KERNEL_ONLY configuration constant.
783 + Update existing MPU ports to correctly disable the MPU before it is
785 + Added contributed port and demo application for a T-Head (formally C-SKY)
790 + Added the vPortGetHeapStats() API function which returns information on
791 the heap_4 and heap_5 state.
792 + Added xTaskCatchUpTicks(), which corrects the tick count value after the
793 application code has held interrupts disabled for an extended period.
794 + Added xTaskNotifyValueClear() API function.
795 + Added uxTimerGetReloadMode() API function.
797 Other miscellaneous changes:
798 + Change type of uxPendedTicks from UBaseType_t to TickType_t to ensure it
799 has the same type as variables with which it is compared to, and therefore
800 also renamed the variable xPendingTicks.
801 + Update Keil projects that use the MPU so memory regions come from linker
802 script (scatter file) variables instead of being hard coded.
803 + Added LPC51U68 Cortex-M0+ demos for GCC (MCUXpresso), Keil and IAR
805 + Added CORTEX_MPU_STM32L4_Discovery_Keil_STM32Cube demo.
806 + Added LPC54018 MPU demo.
807 + Rename xTaskGetIdleRunTimeCounter() to ulTaskGetIdleRunTimeCounter().
810 Changes between FreeRTOS V10.2.1 and FreeRTOS V10.2.0 released May 13 2019:
812 + Added ARM Cortex-M23 port layer to complement the pre-existing ARM
813 Cortex-M33 port layer.
814 + The RISC-V port now automatically switches between 32-bit and 64-bit
816 + Introduced the portMEMORY_BARRIER macro to prevent instruction re-ordering
817 when GCC link time optimisation is used.
818 + Introduced the portDONT_DISCARD macro to the ARMv8-M ports to try and
819 prevent the secure side builds from removing symbols required by the
820 non secure side build.
821 + Introduced the portARCH_NAME to provide additional data to select semi-
822 automated build environments.
823 + Cortex-M33 and Cortex-M23 ports now correctly disable the MPU before
824 updating the MPU registers.
826 + Added Nuvoton NuMaker-PFM-M2351 ARM Cortex-M23 demo.
827 + Added LPC55S69 ARM Cortex-M33 demo.
828 + Added an STM32 dual core AMP stress test demo.
831 Changes between FreeRTOS V10.1.1 and FreeRTOS V10.2.0 released February 25 2019:
833 + Added GCC RISC-V MCU port with three separate demo applications.
834 + Included pre-existing ARM Cortex-M33 (ARMv8-M) GCC/ARMclang and IAR ports
835 with Keil simulator demo.
836 + Update the method used to detect if a timer is active. Previously the
837 timer was deemed to be inactive if it was not referenced from a list.
838 However, when a timer is updated it is temporarily removed from, then
839 re-added to a list, so now the timer's active status is stored separately.
840 + Add vTimerSetReloadMode(), xTaskGetIdleRunTimeCounter(), and
841 xTaskGetApplicationTaskTagFromISR() API functions.
842 + Updated third party Xtensa port so it is MIT licensed.
843 + Added configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H to the Renesas
844 compiler RX600v2 port to enable switching between platform.h and
845 iodefine.h includes within that port's port.c file.
846 + Removed the 'FromISR' functions from the MPU ports as ISRs run privileged
848 + Added uxTaskGetStackHighWaterMark2() function to enable the return type to
849 be changed without breaking backward compatibility.
850 uxTaskGetStackHighWaterMark() returns a UBaseType_t as always,
851 uxTaskGetStackHighWaterMark2() returns configSTACK_DEPTH_TYPE to allow the
852 user to determine the return type.
853 + Fixed issues in memory protected ports related to different combinations
854 of static memory only and dynamic memory only builds. As a result the
855 definition of tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE became more
856 complex and was moved to FreeRTOS.h with a table explaining its definition.
857 + Added a 'get task tag from ISR' function.
858 + Change the method used to determine if a timer is active or not from just
859 seeing if it is referenced from the active timer list to storing its
860 active state explicitly. The change prevents the timer reporting that it
861 is inactive while it is being moved from one list to another.
862 + The pcName parameter passed into the task create functions can be NULL,
863 previously a name had to be provided.
864 + When using tickless idle, prvResetNextTaskUnblockTime() is now only called
865 in xTaskRemoveFromEventList() if the scheduler is not suspended.
866 + Introduced portHAS_STACK_OVERFLOW_CHECKING, which should be set to 1 for
867 FreeRTOS ports that run on architectures that have stack limit registers.
870 Changes between FreeRTOS V10.1.0 and FreeRTOS V10.1.1 released 7 September 2018
872 + Reverted a few structure name changes that broke several kernel aware
874 + Updated to the latest trace recorder code.
875 + Fixed some formatting in the FreeRTOS+TCP TCP/IP stack code.
876 + Reverted moving some variables from file to function scope as doing so
877 broke debug scenarios that require the static qualifier to be removed.
879 Changes between FreeRTOS V10.0.1 and FreeRTOS V10.1.0 released 22 August 2018
881 FreeRTOS Kernel Changes:
883 + Update lint checked MISRA compliance to use the latest MISRA standard, was
884 previously using the original MISRA standard.
885 + Updated all object handles (TaskHandle_t, QueueHandle_t, etc.) to be
886 unique types instead of void pointers, improving type safety. (this was
887 attempted some years back but had to be backed out due to bugs in some
888 debuggers). Note this required the pvContainer member of a ListItem_t
889 struct to be renamed - set configENABLE_BACKWARD_COMPATIBILITY to 1 if
890 this causes an issue.
891 + Added configUSE_POSIX_ERRNO to enable per task POSIX style errno
892 functionality in a more user friendly way - previously the generic thread
893 local storage feature was used for this purpose.
894 + Added Xtensa port and demo application for the XCC compiler.
895 + Changed the implementation of vPortEndScheduler() for the Win32 port to
896 simply call exit( 0 ).
897 + Bug fix in vPortEnableInterrupt() for the GCC Microblaze port to protect
898 the read modify write access to an internal Microblaze register.
899 + Fix minor niggles when the MPU is used with regards to prototype
900 differences, static struct size differences, etc.
901 + The usStackHighWaterMark member of the TaskStatus_t structure now has type
902 configSTACK_DEPTH_TYPE in place of uint16_t - that change should have been
903 made when the configSTACK_DEPTH_TYPE type (which gets around the previous
904 16-bit limit on stack size specifications) was introduced.
905 + Added the xMessageBufferNextLengthBytes() API function and likewise stream
907 + Introduce configMESSAGE_BUFFER_LENGTH_TYPE to allow the number of bytes
908 used to hold the length of a message in the message buffer to be reduced.
909 configMESSAGE_BUFFER_LENGTH_TYPE default to size_t, but if, for example,
910 messages can never be more than 255 bytes it could be set to uint8_t,
911 saving 3 bytes each time a message is written into the message buffer
912 (assuming sizeof( size_t ) is 4).
913 + Updated the StaticTimer_t structure to ensure it matches the size of the
914 Timer_t structure when the size of TaskFunction_t does not equal the size
916 + Update various Xilinx demos to use 2018.1 version of the SDK tools.
917 + Various updates to demo tasks to maintain test coverage.
918 + FreeRTOS+UDP was removed in FreeRTOS V10.1.0 as it was replaced by
919 FreeRTOS+TCP, which was brought into the main download in FreeRTOS
920 V10.0.0. FreeRTOS+TCP can be configured as a UDP only stack, and
921 FreeRTOS+UDP does not contain the patches applied to FreeRTOS+TCP.
923 FreeRTOS+TCP Changes:
925 + Multiple security improvements and fixes in packet parsing routines, DNS
926 caching, and TCP sequence number and ID generation.
927 + Disable NBNS and LLMNR by default.
928 + Add TCP hang protection by default.
930 We thank Ori Karliner of Zimperium zLabs Team for reporting these issues.
933 Changes between FreeRTOS V10.0.0 and FreeRTOS V10.0.1, released December 20 2017
935 + Fix position of "#if defined( __cplusplus )" in stream_buffer.h.
936 + Correct declarations of MPU_xQueuePeek() and MPU_xQueueSemaphoreTake() in
938 + Correct formatting in vTaskList() helper function when it prints the state
939 of the currently executing task.
940 + Introduce #error if stream_buffer.c is built without
941 configUSE_TASK_NOTIFICATIONS set to 1.
942 + Update FreeRTOS+TCP to V2.0.0
943 - Improve the formatting of text that displays the available netword
944 interfaces when FreeRTOS+TCP is used on Windows with WinPCap.
945 - Introduce ipconfigSOCKET_HAS_USER_WAKE_CALLBACK option to enable a user
946 definable callback to execute when data arrives on a socket.
948 Changes between FreeRTOS V9.0.1 and FreeRTOS V10.0.0:
950 The FreeRTOS kernel is now MIT licensed: https://www.FreeRTOS.org/license
952 New Features and components:
954 + Stream Buffers - see https://www.FreeRTOS.org/RTOS-stream-buffer-example.html
955 + Message Buffers - see https://www.FreeRTOS.org//RTOS-message-buffer-example.html
956 + Move FreeRTOS+TCP into the main repository, along with the basic Win32
957 TCP demo FreeRTOS_Plus_TCP_Minimal_Windows_Simulator.
961 + Added demo for TI SimpleLink CC3220 MCU.
962 + Added MPU and non MPU projects for Microchip CEC and MEC 17xx and 51xx
964 + Added CORTEX_MPU_Static_Simulator_Keil_GCC demo to test static allocation
967 Fixes or enhancements:
969 + Cortex-M ports push additional register prior to calling
970 vTaskSwitchContext to ensure 8-byte alignment is maintained. Only
971 important if a user defined tick hook function performs an operation that
972 requires 8-byte alignment.
973 + Optimisations to the implementation of the standard tickless idle mode on
975 + Improvements to the Win32 port including using higher priority threads.
976 + Ensure interrupt stack alignment on PIC32 ports.
977 + Updated GCC TriCore port to build with later compiler versions.
978 + Update mpu_wrappers.c to support static allocation.
979 + The uxNumberOfItems member of List_t is now volatile - solving an issue
980 when the IAR compiler was used with maximum optimization.
981 + Introduced configRECORD_STACK_HIGH_ADDRESS. When set to 1 the stack start
982 address is saved into each task's TCB (assuming stack grows down).
983 + Introduced configINCLUDE_FREERTOS_TASK_C_ADDITIONS_H to allow user defined
984 functionality, and user defined initialisation, to be added to FreeRTOS's
985 tasks.c source file. When configINCLUDE_FREERTOS_TASK_C_ADDITIONS_H is
986 set to 1 a user provided header file called freertos_task_c_additions.h
987 will be included at the bottom of tasks.c. Functions defined in that
988 header file can call freertos_tasks_c_additions_init(), which in turn
989 calls a macro called FREERTOS_TASKS_C_ADDITIONS_INIT(), if it is defined.
990 FREERTOS_TASKS_C_ADDITIONS_INIT() can be defined in FreeRTOSConfig.h.
991 + Introduced configPRE_SUPPRESS_TICKS_AND_SLEEP_PROCESSING( x ) which can be
992 defined by a user in FreeRTOSConfig.h. The macro is called before
993 assessing whether to enter tickless idle mode or not. If the macro sets
994 x to zero then tickless idle mode will not be entered. This allows users
995 to abort tickless idle mode entry before the tickless idle function is
996 even called - previously it was only possible to abort from within the
997 tickless idle function itself.
998 + Added configPRINTF(), which can be defined by users to allow all libraries
999 to use the same print formatter.
1000 + Introduced configMAX() and configMIN() macros which default to standard
1001 max( x, y ) and min( x, y ) macro behaviour, but can be overridden if the
1002 application writer defines the same macros in FreeRTOSConfig.h.
1003 + Corrected the definition of StaticTask_t in the case where
1004 INCLUDE_xTaskAbortDelay is set to 1.
1005 + Introduced configTIMER_SERVICE_TASK_NAME and configIDLE_TASK_NAME, both of
1006 which can be defined to strings in FreeRTOSConfig.h to change the default
1007 names of the timer service and idle tasks respectively.
1008 + Only fill the stack of a newly created task with a known value if stack
1009 checking, or high water mark checking/viewing, is in use - removing the
1010 dependency on memset() in other cases.
1011 + Introduced xTaskCreateRestrictedStatic() so static allocation can be used
1013 + Ensure suspended tasks cannot be unsuspended by a received task
1015 + Fix race condition in vTaskSetTimeOutState().
1016 + Updated trace recorder files to the latest version.
1018 Changes since FreeRTOS V9.0.0:
1020 + Priority dis-inheritance behaviour has been enhanced in the case where a
1021 task that attempted to take a mutex that was held by a lower priority task
1022 timed out before it was able to obtain the mutex (causing the task that
1023 holds the mutex to have its priority raised, then lowered again, in
1024 accordance with the priority inheritance protocol).
1025 + Split the overloaded xQueueGenericReceive() function into three separate
1026 dedicated functions.
1027 + Allow the default human readable text names given to the Idle and Timer
1028 tasks to be overridden by defining the configIDLE_TASK_NAME and
1029 configTIMER_SERVICE_TASK_NAME definitions respectively in FreeRTOSConfig.h.
1030 + Introduced configINITIAL_TICK_COUNT to allow the tick count to take a
1031 value of than than 0 when the system boots. This can be useful for
1032 testing purposes - although setting configUSE_16_BIT_TICKS to 1 can also
1033 be used to test frequent tick overflows.
1034 + Ensure the Cortex-M SysTick count is cleared to zero before starting the
1036 + Add configASSERT() into ARM Cortex-M ports to check the number of priority
1038 + Clear the 'control' register before starting ARM Cortex-M4F ports in case
1039 the FPU is used before the scheduler is started. This just saves a few
1040 bytes on the main stack as it prevents space being left for a later save
1042 + Added xSemaphoreGetMutexHolderFromISR().
1043 + Corrected use of portNVIC_PENDSVSET to portNVIC_PENDSVSET_BIT in MPU ports.
1044 + Introduced configSTACK_DEPTH_TYPE to allow users to change the type used
1045 to specify the stack size when using xTaskCreate(). For historic reasons,
1046 when FreeRTOS was only used on small MCUs, the type was set to uint16_t,
1047 but that can be too restrictive when FreeRTOS is used on larger
1048 processors. configSTACK_DEPTH_TYPE defaults to uint16_t.
1049 xTaskCreateStatic(), being a newer function, used a uint32_t.
1050 + Increase the priority of the Windows threads used by the Win32 port. As
1051 all the threads run on the same core, and the threads run with very high
1052 priority, there is a risk that the host will become unresponsive, so also
1053 prevent the Windows port executing on single core hosts.
1055 Changes between FreeRTOS V9.0.0 and FreeRTOS V9.0.0rc2 released May 25 2016:
1057 See https://www.FreeRTOS.org/FreeRTOS-V9.html
1059 RTOS kernel updates:
1061 + The prototype of the new xTaskCreateStatic() API function was modified to
1062 remove a parameter and improve compatibility with other new
1063 "CreateStatic()" API functions. The stack size parameter in
1064 xTaskCreateStatic() is now uint32_t, which changes the prototype of the
1065 callback functions. See the following URL:
1066 https://www.FreeRTOS.org/xTaskCreateStatic.html
1067 + GCC ARM Cortex-A port: Introduced the configUSE_TASK_FPU_SUPPORT
1068 constant. When configUSE_TASK_FPU_SUPPORT is set to 2 every task is
1069 automatically given a floating point (FPU) context.
1070 + GCC ARM Cortex-A port: It is now possible to automatically save and
1071 restore all floating point (FPU) registers on entry to each potentially
1072 nested interrupt by defining vApplicationFPUSafeIRQHandler() instead of
1073 vApplicationIRQHandler().
1074 + All ARM Cortex-M3/4F/7 ports: Clear the least significant bit of the task
1075 entry address placed onto the stack of a task when the task is created for
1076 strict compliance with the ARM Cortex-M3/4/7 architecture documentation
1077 (no noticeable effect unless using the QMEU emulator).
1078 + Added GCC and Keil ARM Cortex-M4F MPU ports - previously the MPU was only
1079 supported on ARM Cortex-M3.
1080 + ARM Cortex-M3/4F MPU ports: Update to fully support the FreeRTOS V9.0.0
1081 API (other than static object creation) and added the
1082 FreeRTOS/Demo/CORTEX_MPU_Simulator_Keil_GCC demo application to
1083 demonstrate how to use the updated MPU port.
1084 + All ARM Cortex-M3/4F/7 ports: Add additional barrier instructions to the
1085 default low power tickless implementation.
1086 + All ARM Cortex-M0 ports: Prevent an item being left on the stack of the
1087 first task that executes.
1088 + Win32 ports: Reduce the amount of stack used and change the way Windows
1089 threads are deleted to increase the maximum execution time.
1090 + Add an ARM Cortex-M4F port for the MikroC compiler. Ensure to read the
1091 documentation page for this port before use.
1092 + MPS430X IAR port: Update to be compatible with the latest EW430 tools
1094 + IAR32 GCC port: Correct vPortExitCritical() when
1095 configMAX_API_CALL_INTERRUPT_PRIORITY == portMAX_PRIORITY.
1096 + For consistency vTaskGetTaskInfo() now has the alias vTaskGetInfo(),
1097 xTaskGetTaskHandle() now has the alias xTaskGetHandle() and
1098 pcQueueGetQueueName() now has an alias pcQueueGetName().
1099 + Fix various errors in comments and compiler warnings.
1101 Demo application updates:
1103 + Update Atmel Studio projects to use Atmel Studio 7.
1104 + Update Xilinx SDK projects to use the 2016.1 version of the SDK.
1105 + Remove dependency on legacy IO libraries from the PIC32 demos.
1106 + Move the Xilinx UltraScale Cortex-R5 demo into the main distribution.
1107 + Update the MSP432 libraries to the latest version.
1108 + Add Microchip CEC1302 (ARM Cortex-M4F) demos for GCC, Keil and MikroC
1110 + Move the Atmel SAMA5D2 demo into the main distribution.
1112 Changes between FreeRTOS V9.0.0rc1 and FreeRTOS V9.0.0rc2 (release candidate 2)
1113 released March 30 2016:
1115 NOTE - See https://www.FreeRTOS.org/FreeRTOS-V9.html for details
1117 + The functions that create RTOS objects using static memory allocation have
1118 been simplified and will not revert to using dynamic allocation if a
1119 buffer is passed into a function as NULL.
1120 + Introduced the configSUPPORT_DYNAMIC_ALLOCATION configuration constant to
1121 allow a FreeRTOS application to be built without a heap even being being
1122 defined. The Win32 example located in the
1123 /FreeRTOS/demo/WIN32-MSVC-Static-Allocation-Only directory is provided as
1124 a reference for projects that do not include a FreeRTOS heap.
1125 + Minor run-time optimisations.
1126 + Two new low power tickless implementations that target Silicon Labs EFM32
1128 + Addition of the xTimerGetPeriod() and xTimerGetExpireTime() API functions.
1130 Changes between FreeRTOS V8.2.3 and FreeRTOS V9.0.0rc1 (release candidate 1)
1131 released February 19 2016:
1133 RTOS Kernel Updates:
1135 + Major new feature - tasks, semaphores, queues, timers and event groups can
1136 now be created using statically allocated memory, so without any calls to
1138 + Major new features - Added the xTaskAbortDelay() API function which allows
1139 one task to force another task to immediately leave the Blocked state,
1140 even if the event the blocked task is waiting for has not occurred, or the
1141 blocked task's timeout has not expired.
1142 + Updates necessary to allow FreeRTOS to run on 64-bit architectures.
1143 + Added vApplicationDaemonTaskStartupHook() which executes when the RTOS
1144 daemon task (which used to be called the timer service task) starts
1145 running. This is useful if the application includes initialisation code
1146 that would benefit from executing after the scheduler has been started.
1147 + Added the xTaskGetTaskHandle() API function, which obtains a task handle
1148 from the task's name. xTaskGetTaskHandle() uses multiple string compare
1149 operations, so it is recommended that it is called only once per task.
1150 The handle returned by xTaskGetTaskHandle() can then be stored locally for
1152 + Added the pcQueueGetQueueName() API function, which obtains the name of
1153 a queue from the queue's handle.
1154 + Tickless idling (for low power applications) can now also be used when
1155 configUSE_PREEMPTION is 0.
1156 + If one task deletes another task, then the stack and TCB of the deleted
1157 task is now freed immediately. If a task deletes itself, then the stack
1158 and TCB of the deleted task are freed by the Idle task as before.
1159 + If a task notification is used to unblock a task from an ISR, but the
1160 xHigherPriorityTaskWoken parameter is not used, then pend a context switch
1161 that will then occur during the next tick interrupt.
1162 + Heap_1.c and Heap_2.c now use the configAPPLICATION_ALLOCATED_HEAP
1163 settings, which previously was only used by heap_4.c.
1164 configAPPLICATION_ALLOCATED_HEAP allows the application writer to declare
1165 the array that will be used as the FreeRTOS heap, and in-so-doing, place
1166 the heap at a specific memory location.
1167 + TaskStatus_t structures are used to obtain details of a task.
1168 TaskStatus_t now includes the bae address of the task's stack.
1169 + Added the vTaskGetTaskInfo() API function, which returns a TaskStatus_t
1170 structure that contains information about a single task. Previously this
1171 information could only be obtained for all the tasks at once, as an array
1172 of TaskStatus_t structures.
1173 + Added the uxSemaphoreGetCount() API function.
1174 + Replicate previous Cortex-M4F and Cortex-M7 optimisations in some
1175 Cortex-M3 port layers.
1177 Demo Application Updates:
1179 Further demo applications will be added prior to the final FreeRTOS V9
1182 + Updated SAM4L Atmel Studio project to use Atmel Studio 7.
1183 + Added ARM Cortex-A53 64-bit port.
1184 + Added a port and demo for the ARM Cortex-A53 64-bit cores on the Xilinx
1186 + Added Cortex-M7 SAME70 GCC demo.
1187 + Added EFM32 Giant and Wonder Gecko demos.
1190 Changes between V8.2.2 and V8.2.3 released October 16, 2015
1192 RTOS kernel updates:
1194 + Fix bug identified in a modification made in V8.2.2 to the software timer
1195 code that allows tickless low power applications to sleep indefinitely
1196 when software timers are used.
1197 + Simplify and improve efficiency of stack overflow checking.
1198 + Add xTaskNotifyStateClear() API function.
1199 + New IAR and GCC Cortex-R ports for microprocessors that do not use an ARM
1200 generic interrupt controller (GIC).
1201 + New PIC32MEC14xx port.
1202 + Add support for PIC32MZ EF parts (with floating point) into the PIC32MZ
1204 + Zynq7000 port layer now declares the functions that setup and clear the
1205 tick interrupt as weak symbols so they can be overridden by the
1206 application, and uses a global XScuGic object so the same object can be
1207 used by the application code.
1208 + Introduced configUSE_TASK_FPU_SUPPORT, although the PIC32MZ EF port is
1209 currently the only port that uses it.
1210 + Updates to RL78 and 78K0 IAR port layers to improve support for
1211 combinations of memory models.
1212 + Minor updates to heap_5.c to remove compiler warnings generated by some
1214 + License simplifications. See /FreeRTOS/License/license.txt in the
1215 official distribution.
1219 + Update directory names to use WolfSSL instead of CyaSSL, inline with
1220 WolfSSL's re-branding.
1221 + Update to latest WolfSSL code.
1222 + Update to latest FreeRTOS+Trace recorder code.
1223 + Add in the FreeRTOS+Trace recorder library required for streaming trace.
1225 Demo application changes:
1227 + Add demo applications for Renesas RZ/T (Cortex-R), PIC32MZ EF (PIC32 with
1228 floating point hardware), PIC32MEC14xx, RX71M, RX113 and RX231.
1229 + General tidy up of spelling and compiler warnings.
1232 Changes between V8.2.1 and V8.2.2 released August 12, 2015
1234 RTOS kernel updates:
1236 + Added Intel IA32/x86 32-bit port.
1237 + General maintenance.
1238 + PRIVILEGED_FUNCTION and PRIVILEGED_DATA macros, which are used in memory
1239 protected systems, have been added to the newer event group and software
1241 + Add the errno definitions used by FreeRTOS+ components into projdefs.h.
1242 + Remove the restriction that prevented tick-less idle implementations
1243 waiting indefinitely when software timers were used in the same
1245 + Introduce xTaskNotifyAndQueryFromISR() as the interrupt safe version of
1246 xTaskNotifyAndQuery().
1247 + Add additional NOPs to the MSP430X port layers to ensure strict compliance
1248 with the hardware documentation.
1249 + Microblaze port: Added option for port optimised task selection.
1250 + Microblaze port: Previously tasks inherited the exception enable state
1251 at the time the task was created. Now all tasks are created with
1252 exceptions enabled if the Microblaze design supports exceptions.
1253 + Windows port: Add additional safe guards to ensure the correct start up
1254 sequence and thread switching timing.
1255 + Windows port: Improve the implementation of the port optimised task
1256 selection assembly code.
1257 + Update heap_4 and heap_5 to allow use on 64-bit processors.
1258 + Simplify the code that creates a queue.
1259 + General improved tick-less idle behaviour.
1260 + Ensure none of the variables in the common kernel files are initialised to
1261 anything other than zero.
1262 + Correct calculation of xHeapStructSize in heap_4 and heap_5.
1264 Demo application updates:
1266 + Added demo project for the new IA32/x86 port that targets the Galileo
1268 + Added MSP430FR5969 demos (previously provided as a separate download).
1269 + Added FreeRTOS BSP repository for automatic creation of FreeRTOS
1270 applications in the Xilinx SDK.
1271 + Added Atmel Studio / GCC project for the SAMV71 (ARM Cortex-M7)
1272 + Update Xilinx SDK projects to use version 2015.2 of the SDK.
1273 + Remove Microblaze demos that were using obsolete tools.
1274 + Add MSP43FR5969 IAR and CCS demos.
1278 + Updated FreeRTOS+Trace recorder library, which requires an update to the
1279 FreeRTOS+Trace application.
1280 + Added Reliance Edge source code and demo application. Reliance edge is
1281 a fail safe transactional file system ideal for applications that require
1282 file storage, and especially when high reliability is essential.
1283 + Introduce configAPPLICATION_PROVIDES_cOutputBuffer to allow FreeRTOS+CLI
1284 users to place the output buffer at a fixed memory address.
1285 + Improve the NetworkInterface.c file provided for the Windows port of
1288 Changes between V8.2.0 and V8.2.1 released 24th March 2015.
1290 RTOS kernel updates:
1292 + Added user definable and flexible thread local storage facility.
1293 + Added vTimerSetTimerID() API function to complement the pvTimerGetTimerID()
1294 function to allow the timer's ID to be used as timer local storage.
1295 + Fixed a potential issue related to the use of queue sets from an ISR.
1296 + Some updates to the Xilinx Microblaze GCC port.
1297 + Added ARM Cortex-M4F port for Texas Instruments Code Composer Studio.
1298 + Added ARM Cortex-M7 r0p1 port layer for IAR, GCC and Keil which contains a
1299 minor errata work around. All other ARM Cortex-M7 core revisions should
1300 use the ARM Cortex-M4F port.
1301 + Exclude the whole of croutine.c if configUSE_CO_ROUTINES is set to 0.
1302 + Change some data types from uint32_t to size_t in preparation for 64-bit
1304 + Update the PIC32 port to remove deprecation warnings output by the latest
1306 + Fix bug when xQueueOverwrite() and xQueueOverwrite() from ISR are used to
1307 overwrite items in two queues that are part of the same set.
1309 Demo application updates:
1311 + Added demo application for TI's ARM Cortex-M4F based MSP432
1312 microcontroller using IAR, Keil and CCS compilers.
1313 + Added demo application for STM32F ARM Cortex-M7 based microcontroller
1315 + Added demo application for Atmel SAMV71 ARM Cortex-M7 based
1316 microcontroller using IAR and Keil.
1317 + Added Microblaze demo that uses the 2014.4 version of the Xilinx SDK and
1318 runs on the KC705 evaluation board (Kintex FPGA).
1320 Changes between V8.1.2 and V8.2.0 released 16th January 2015
1322 Changes between release candidate 1 and the official release are restricted
1323 to maintenance only.
1325 Significant RTOS kernel updates:
1327 + MAJOR NEW FEATURE! Task notifications. Please see the following URL for
1328 details: https://www.FreeRTOS.org/RTOS-task-notifications.html
1329 + NEW HEADER FILE REQUIRED! Obsolete definitions have been separated into
1330 a new header file called FreeRTOS/Source/include/deprecated_definitions.h.
1331 This header file must be present to build. Note some of the obsolete
1332 definitions are still used by very old demo application projects.
1334 Other RTOS kernel updates:
1336 + Made xSemaphoreGiveFromISR() a function rather than a macro that calls
1337 xQueueGenericSendFromISR(). This allows for major performance
1338 enhancements at the expense of some additional code size if both functions
1339 are used in the same application. NOTE: In most uses cases such use of
1340 a semaphore can now be replaced with a task notification which is smaller
1342 + The TCB is now always allocated such that the task's stack grows away from
1343 the TCB (improves debugging of stack overflows as the overflow will not
1344 overwrite the task's name).
1345 + GCC, IAR and Keil Cortex-M4F ports now use more inlining (performance
1346 enhancements at the cost of a little additional code space).
1347 + Queues are now allocated with a single call to pvPortMalloc() which
1348 allocates both the queue structure and the queue storage area.
1349 + Introduced a new critical section macro for reading the tick count that
1350 defines away to nothing in cases where the width of the tick allows the
1351 tick count to be read atomically (performance benefits - especially when
1352 optimisation is on).
1353 + Introduced configAPPLICATION_ALLOCATED_HEAP in heap_4.c to allow the
1354 application writer to provide their own heap array - and in so doing
1355 control the location of the heap.
1356 + Introduced configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES which, when set, will
1357 include known values in both list and list item structures. The values
1358 are intended to assist debugging. If the values get overwritten then it
1359 is likely application code has written over RAM used by the kernel.
1360 + configASSERT()s in all Cortex-M ports used to test the lowest 5 bits of
1361 the interrupt control register to detect taskENTER_CRITICAL() being called
1362 from an interrupt. This has been changed to test all 8 bits.
1363 + Introduced uxTaskPriorityGetFromISR().
1364 + Microblze V8 port now tests XPAR_MICROBLAZE_0_USE_FPU for inequality to 0
1365 rather than equality to 1, and 2 and 3 are also valid values.
1366 + Cortex-A5 GIC-less port no longer passes the address of the interrupting
1367 peripheral into the interrupt handler.
1368 + Fix an issue in FreeRTOS-MPU where an attempt was made to free the stack
1369 belonging to a task when the task was deleted, even when the stack was
1370 allocated statically.
1371 + Utility (helper) functions that format task statistic information into
1372 human readable tables now pad task names with spaces to ensure columns
1373 line up correctly even where task name lengths vary greatly.
1374 + Update FreeRTOS+Trace recorder library to version 2.7.0.
1376 Demo application updates:
1378 + Added two new standard demo task sets: IntSemTest and TaskNotify.
1379 + Added port and demo application for Atmel SAMA5D4 Cortex-A5 MPU.
1380 + Added demo application for Altera Cyclone V Cortex-A9 MPU.
1381 + Updated Zynq demo to use version 2014.4 of Xilinx's SDK and added in
1382 demo tasks for new RTOS features.
1383 + Updated Atmel SAM4E and SAM4S demos to include a lot of additional test
1385 + Fixed a corner case issue in Atmel SAM4L low power tickless
1386 implementation, and added button interrupt handling.
1387 + Make the interrupt queue tests more tolerant to heave CPU loads.
1388 + Updated MSVC FreeRTOS simulator demo to include the latest standard test
1390 + Updated MingW/Eclipse FreeRTOS simulator demo to match the FreeRTOS MSVC
1392 + Updated all demos that use FreeRTOS+Trace to work with the latest trace
1396 Changes between V8.1.1 and V8.1.2 released September 2nd 2014
1398 Move the defaulting of configUSE_PORT_OPTIMISED_TASK_SELECTION into the
1399 individual port layers where necessary so it does not affect ports that do
1400 not support the definition.
1402 Changes between V8.1.0 and V8.1.1 released August 29th 2014
1404 By popular requests - a minor patch to V8.1.0 to re-instate the ability to
1405 give a mutex type semaphore (with priority inheritance) from an interrupt
1408 Changes between V8.0.1 and V8.1.0 released August 26th 2014
1410 FreeRTOS scheduler, kernel, demo and test updates:
1412 + Improved the priority inheritance algorithms to assist integration with
1413 off the shelf middleware that may hold multiple mutexes simultaneously.
1414 + Introduce heap_5.c, which is similar to heap_4.c but allows the heap to
1415 span multiple non-contiguous memory regions.
1416 + Updated all Cortex-A9 ports to help trap a couple of common usage errors -
1417 the first being when a task incorrectly attempts to exit its implementing
1418 function and the second being when a non interrupt safe API function is
1419 called from an interrupt.
1420 + Update all Cortex-A9 ports to remove obsolete mode switches prior to
1421 restoring a task context.
1422 + configUSE_PORT_OPTIMISED_TASK_SELECTION now defaults to 1 instead of 0.
1423 + Update all Cortex-M3/4F ports to trap a non interrupt safe API function
1424 being called from an interrupt handler.
1425 + Simplify the alignment checks in heap_4.c.
1426 + Update the MSVC Windows simulator demo to use heap_5.c in place of
1427 heap_4.c to ensure end users have an example to refer to.
1428 + Updated standard demo test code to test the new priority inheritance
1430 + Updated the standard demo tasks to make use of stdint and the FreeRTOS
1431 specific typedefs that were introduced in FreeRTOS V8.0.0.
1432 + Introduce the pdMS_TO_TICKS() macro as a more user friendly and intuitive
1433 alternative to pdTICKS_PER_MS - both of which can be used to convert a
1434 time specified in milliseconds to a time specified in RTOS ticks.
1435 + Fix a bug in the Tasking compiler's Cortex-M port that resulted in an
1436 incorrect value being written to the basepri register. This only effects
1437 users of the Tasking compiler.
1438 + Update the Zynq demo to use version 2014.2 of the SDK and add in an lwIP
1439 example that demonstrates lwIP being used with both its raw and sockets
1441 + Updated the CCS Cortex-R4 port to enable it to be built with the latest
1444 New ports and demo applications:
1446 + Two Renesas RX64M ports (RXv2 core) and demos introduced, one for the GCC
1447 compiler and one for the Renesas compiler. Both demos use e2 studio.
1448 + Generic IAR Cortex-A5 port (without any reliance on a GIC) introduced.
1449 The new port is demonstrated on an Atmel SAMA5D3 XPlained board.
1451 FreeRTOS+ component updates:
1453 + Update CyaSSL to the latest version.
1454 + Updated the FreeRTOS+ components supplied directly by Real Time Engineers
1455 Ltd. to make use of stdint and the FreeRTOS specific typedefs that were
1456 introduced in FreeRTOS V8.0.0.
1457 + Rework and simplify the FreeRTOS+FAT SL RAM disk driver.
1459 Miscellaneous updates and maintenance:
1461 + Update the IAR and DS-5/ARM RZ demos to target the official RZ RSK
1462 hardware in place of the previously targeted Renesas internal (not
1463 publicly available) hardware.
1464 + Various other maintenance tasks.
1467 Changes between V8.0.0 and V8.0.1 released 2nd May 2014
1469 + Minor fixes to the event group functionality that was released in V8.0.0.
1470 The 'clear bits from ISR' functionality is now implemented using a
1471 deferred interrupt callback instead of a function, and the 'wait bits' and
1472 'task sync' functions now correctly clear internal control bits before
1473 returning a value in every possible path through the respective functions.
1474 + Ensure the updating of internal control data is protected by a critical
1475 section after a task is deleted or suspended.
1476 + Minor fixes to FreeRTOS+FAT SL - namely seeking beyond the end of a file
1477 when the offset was not a multiple of the sector size.
1478 + Ensure Cortex-A9 system registers are only ever accessed as 32-bit values,
1479 even when only the lest significant byte of the register is implemented.
1483 + Updated the XMC4200 IAR project so it links with version 7.x of the IAR
1486 + Add pcTimerGetName() API function.
1487 + Call _reclaim_reent() when a task is deleted if configUSE_NEWLIB_REENTRANT
1490 Changes between V7.6.0 and V8.0.0 released 19th Feb 2014
1492 https://www.FreeRTOS.org/upgrading-to-FreeRTOS-V8.html
1494 FreeRTOS V8.x.x is a drop-in compatible replacement for FreeRTOS V7.x.x,
1495 although a change to the type used to reference character strings may result
1496 in application code generating a few (easily clearable) compiler warnings
1497 after the upgrade, and an updated typedef naming convention means use of the
1498 old typedef names is now discouraged.
1499 See https://www.FreeRTOS.org/upgrading-to-FreeRTOS-V8.html for full
1502 New features and functionality:
1504 + Event groups - see https://www.FreeRTOS.org/FreeRTOS-Event-Groups.html
1505 + Centralised deferred interrupt processing - see
1506 https://www.FreeRTOS.org/xTimerPendFunctionCallFromISR.html
1510 + Previously, when a task left the Blocked state, a context switch was
1511 performed if the priority of the unblocked task was greater than or equal
1512 to the priority of the Running task. Now a context switch is only
1513 performed if the priority of the unblocked task is greater than the
1514 priority of the Running task.
1515 + New low power tickless demonstration project that targets the ST STM32L
1516 microcontroller - see
1517 https://www.FreeRTOS.org/STM32L-discovery-low-power-tickless-RTOS-demo.html
1518 + Add xPortGetMinimumEverFreeHeapSize() to heap_4.c.
1519 + Small change to the tickless low power implementation on the SAM4L to
1520 ensure the alarm value (compare match value) cannot be set to zero when a
1521 tickless period is exited due to an interrupt originating from a source
1522 other than the RTOS tick.
1523 + Update the GCC/Eclipse Win32 simulator demo to make better use of Eclipse
1524 resource filters and match the functionality of the MSVC equivalent.
1525 + xTaskIsTaskSuspended() is no longer a public function. Use
1526 eTaskGetState() in its place.
1527 + Improved trace macros, including tracing of heap usage.
1528 + Remove one level of indirection when accepting interrupts on the PIC32MZ.
1529 + Add Cortex-A9 GCC port layer.
1530 + Add Xilinx Zynq demo application.
1533 Changes between V7.5.3 and V7.6.0 released 18th November 2013
1535 V7.6.0 changes some behaviour when the co-operative scheduler is used (when
1536 configUSE_PREEMPTION is set to 0). It is important to note that the
1537 behaviour of the pre-emptive scheduler is unchanged - the following
1538 description only applies when configUSE_PREEMPTION is set to 0:
1540 WHEN configUSE_PREEMPTION IS SET TO 0 (which is in a small minority of
1541 cases) a context switch will now only occur when a task places itself into
1542 the Blocked state, or explicitly calls taskYIELD(). This differs from
1543 previous versions, where a context switch would also occur when implicitly
1544 moving a higher priority task out of the Blocked state. For example,
1545 previously, WHEN PREEMPTION WAS TURNED OFF, if task A unblocks task B by
1546 writing to a queue, then the scheduler would switch to the higher priority
1547 task. Now, WHEN PREEMPTION IS TURNED OFF, if task A unblocks task B by
1548 writing to a queue, task B will not start running until task A enters the
1549 Blocked state or task A calls taskYIELD(). [If configUSE_PREEMPTION is not
1550 set to 0, so the normal pre-emptive scheduler is being used, then task B
1551 will start running immediately that it is moved out of the Blocked state].
1555 + Added a port layer and a demo project for the new PIC32MZ architecture.
1556 + Update the PIC32MX port layer to re-introduce some ehb instructions that
1557 were previously removed, add the ability to catch interrupt stack
1558 overflows (previously only task stack overflows were trapped), and also
1559 add the ability to catch an application task incorrectly attempting to
1560 return from its implementing function.
1561 + Make dramatic improvements to the performance of the Win32 simulator port
1563 + Ensure tasks that are blocked indefinitely report their state as Blocked
1564 instead of Suspended.
1565 + Slight improvement to the Cortex-M4F port layers where previously one
1566 register was inadvertently being saved twice.
1567 + Introduce the xSemaphoreCreateBinary() API function to ensure consistency
1568 in the semantics of how each semaphore type is created. It is no longer
1569 recommended to use vSemaphoreCreateBinary() (the version prefixed with a
1570 'v'), although it will remain in the code for backward compatibility.
1571 + Update the Cortex-M0 port layers to allow the scheduler to be started
1572 without using the SVC handler.
1573 + Added a build configuration to the PIC32MX MPLAB X demo project that
1574 targets the PIC32 USB II starter kit. Previously all the build
1575 configurations required the Explorer 16 hardware.
1576 + Some of the standard demo tasks have been updated to ensure they execute
1577 correctly with the updated co-operative scheduling behaviour.
1578 + Added comprehensive demo for the Atmel SAM4E, including use of
1579 FreeRTOS+UDP, FreeRTOS+FAT SL and FreeRTOS+CLI.
1583 + Minor maintenance on FreeRTOS+UDP.
1585 Changes between V7.5.2 and V7.5.3 released October 14 2013
1589 + Prior to V7.5.x yields requested from the tick hook would occur in the
1590 same tick interrupt - revert to that original behaviour.
1591 + New API function uxQueueSpacesAvailable().
1592 + Introduced the prvTaskExitError() function to Cortex-M0, Cortex-M3/4
1593 and Cortex-M4F ports. prvTaskExitError() is used to trap tasks that
1594 attempt to return from their implementing functions (tasks should call
1595 vTaskDelete( NULL ); if they want to exit).
1596 + The Cortex-M0 version of portSET_INTERRUPT_MASK_FROM_ISR and
1597 portCLEAR_INTERRUPT_MASK_FROM_ISR are now fully nestable.
1598 + Improved behaviour and robustness of the default Cortex-M tickless idle
1600 + Add workaround for silicon errata PMU_CM001 in Infineon XMC4000 devices to
1601 all Cortex-M4F ports.
1602 + Add Cortex-M0 port for Keil.
1603 + Updated Cortus port.
1604 + Ensure _impure_ptr is initialised before the scheduler is started.
1605 Previously it was not set until the first context switch.
1609 + Update FreeRTOS+UDP to V1.0.1 - including direct integration of the
1610 FreeRTOS+Nabto task, improvements to the DHCP behaviour, and a correction
1611 to the test that prevents the network event hook being called on the first
1612 network down event. The FreeRTOS+UDP change history is maintained
1614 + Correct the __NVIC_PRIO_BITS setting in the LPC18xx.h header files
1615 provided in the NXP CMSIS library, then update the interrupts used by the
1616 LPC18xx demos accordingly.
1617 + Replace double quotes (") with single quotes (') in FreeRTOS+CLI help
1618 strings to ensure the strings can be used with the JSON descriptions used
1619 in the FreeRTOS+Nabto demos.
1621 Demo and miscellaneous changes:
1623 + Added demo for the Atmel SAMD20 Cortex-M0+. The demo includes
1625 + Added a demo for the Infineon Cortex-M0 that can be built with the IAR
1627 + Updated the Infineon XMC4000 demos for IAR, Keil, GCC and Tasking tools,
1628 with additional build configurations to directly support the XMC4200 and
1629 XMC4400 devices, in addition to the previously supported XMC4500.
1630 + Updated the demo application.
1631 + Added additional trace macros traceMALLOC and traceFREE to track heap
1634 Changes between V7.5.0 and V7.5.2 released July 24 2013
1636 V7.5.2 makes the new Cortex-M vPortCheckInterruptPriority() function
1637 compatible with the STM32 standard peripheral driver library, and adds
1638 an extra critical section to the default low power tickless mode
1639 implementation. Only users of the STM32 peripheral library or the default
1640 tickless implementation need update from version 7.5.0.
1642 Changes between V7.4.2 and V7.5.0 released July 19 2013
1644 V7.5.0 is a major upgrade that includes multiple scheduling and efficiency
1645 improvements, and some new API functions.
1647 Compatibility information for FreeRTOS users:
1648 FreeRTOS V7.5.0 is backward compatible with FreeRTOS V7.4.0 with one
1649 exception; the vTaskList() and vTaskGetRunTimeStats() functions are now
1650 considered legacy, having been replaced by the single uxTaskGetSystemState()
1651 function. configUSE_STATS_FORMATTING_FUNCTIONS must be set to 1 in
1652 FreeRTOSConfig.h for vTaskList() and vTaskGetRunTimeStats() to be
1655 Compatibility information for FreeRTOS port writers:
1656 vTaskIncrementTick() is now called xTaskIncrementTick() (because it now
1661 + Multiple scheduling and efficiency improvements.
1662 + Core kernel files now pass PC-Lint V8 static checking without outputting
1663 any warnings (information on the test conditions will follow).
1667 + uxTaskGetSystemState() https://www.FreeRTOS.org/uxTaskGetSystemState.html
1668 + xQueueOverwrite() https://www.FreeRTOS.org/xQueueOverwrite.html
1669 + xQueueOverwriteFromISR()
1670 + xQueuePeekFromISR()
1672 The following ports and demos, which were previously available separately,
1673 are now incorporated into the main FreeRTOS zip file download:
1676 + ARM Cortex-A9 ARM compiler
1678 + Microsemi SmartFusion2
1680 New FreeRTOSConfig.h settings
1681 https://freertos.org/a00110.html
1683 + configUSE_TIME_SLICING
1684 + configUSE_NEWLIB_REENTRANT
1685 + configUSE_STATS_FORMATTING_FUNCTIONS
1686 + configINCLUDE_APPLICATION_DEFINED_PRIVILEGED_FUNCTIONS
1690 + (MPU port only) The configINCLUDE_APPLICATION_DEFINED_PRIVILEGED_FUNCTIONS
1691 options provides a mechanism that allows application writers to execute
1692 certain functions in privileged mode even when a task is running in user
1694 + Ports that support interrupt nesting now include a configASSERT() that
1695 will trigger if an interrupt safe FreeRTOS function is called from an
1696 interrupt that has a priority designated as above the maximum system/API
1697 call interrupt priority.
1698 + The included FreeRTOS+Trace recorder code has been updated to the latest
1699 version, and the demo applications that use the trace recorder code have
1700 been updated accordingly.
1701 + The FreeRTOS Windows Simulator (MSVC version only) has been updated to
1702 include a new basic 'blinky' build option in addition to the original
1703 comprehensive build option.
1704 + Improve RAM usage efficiency of heap_4.c and heap_2.c.
1705 + Prevent heap_4.c from attempting to free memory blocks that were not
1706 allocated by heap_4.c, or have already been freed.
1707 + As FreeRTOS now comes with FreeRTOS+FAT SL (donated by HCC) the Chan FATfs
1708 files have been removed from FreeRTOS/Demo/Common.
1709 + Fix build error when R4 port is build in co-operative mode.
1710 + Multiple port and demo application maintenance activities.
1712 Changes between V7.4.1 and V7.4.2 released May 1 2013
1714 NOTE: There are no changes in the FreeRTOS kernel between V7.4.1 and V7.4.2
1716 + Added FreeRTOS+FAT SL source code and demo project. The demo project
1717 runs in the FreeRTOS Windows simulator for easy and hardware independent
1718 experimentation and evaluation. See https://www.FreeRTOS.org/fat_sl
1720 Changes between V7.4.0 and V7.4.1 released April 18 2013
1722 + To ensure strict conformance with the spec and ensure compatibility with
1723 future chips data and instruction barrier instructions have been added to
1724 the yield macros of Cortex-M and Cortex-R port layers. For efficiency
1725 the Cortex-M port layer "yield" and "yield" from ISR are now implemented
1726 separately as the barrier instructions are not required in the ISR case.
1727 + Added FreeRTOS+UDP into main download.
1728 + Reorganised the FreeRTOS+ directory so it now matches the FreeRTOS
1729 directory with Source and Demo subdirectories.
1730 + Implemented the Berkeley sockets select() function in FreeRTOS+UDP.
1731 + Changed (unsigned) casting in calls to standard library functions with
1733 + Added the Atmel SAM4L and Renesas RX100 demos that demonstrates the
1734 tickless (tick suppression) low power FreeRTOS features.
1735 + Add a new RL78 IAR demo that targets numerous new RL78 chips and
1737 + Adjusted stack alignment on RX200 ports to ensure an assert was not
1738 falsely triggered when configASSERT() is defined.
1739 + Updated the Cortex_M4F_Infineon_XMC4500_IAR demo to build with the latest
1741 + Corrected header comments in the het.c and het.h files (RM48/TMS570 demo).
1744 Changes between V7.3.0 and V7.4.0 released February 20 2013
1746 + New feature: Queue sets. See:
1747 https://www.FreeRTOS.org/Pend-on-multiple-rtos-objects.html
1748 + Overhauled the default tickless idle mode implementation provided with the
1749 ARM Cortex-M3 port layers.
1750 + Enhanced tickless support in the core kernel code with the introduction of
1751 the configEXPECTED_IDLE_TIME_BEFORE_SLEEP macro and the
1752 eTaskConfirmSleepModeStatus() function.
1753 + Added the QueueSet.c common demo/test file. Several demo applications
1754 have been updated to use the new demo/test tasks.
1755 + Removed reliance on the PLIB libraries from the MPLAB PIC32 port layer and
1757 + Added the FreeRTOS+Trace recorder code to the MSVC Win32 demo.
1758 + Renamed eTaskStateGet() to eTaskGetState() for consistency, and added a
1759 pre-processor macro for backward compatibility with the previous name.
1760 + Updated functions implemented in the core queue.c source file to allow
1761 queue.h to be included from the .c file directly (this prevents compiler
1762 warnings that were generated by some compilers).
1763 + Updated the CCS Cortex-R4 port layer to replace the CLZ assembler function
1764 with the CLZ compiler intrinsic that is provided by the latest versions of
1765 the CCS ARM compiler.
1766 + Updated all heap_x.c implementations to replace the structure that was
1767 used to ensure the start of the heap was aligned with a more portable
1768 direct C code implementation.
1769 + Added support for PIC24 devices that include EDS.
1770 + Minor optimisations to the PIC32 port layer.
1771 + Minor changes to tasks.c that allow the state viewer plug-ins to display
1772 additional information.
1773 + Bug fix: Update prvProcessReceivedCommands() in timers.c to remove an
1774 issue that could occur if the priority of the timer daemon task was set
1775 below the priority of tasks that used timer services.
1776 + Update the FreeRTOS+Trace recorder code to the latest version.
1778 Changes between V7.2.0 and V7.3.0 released October 31 2012
1780 + Added ability to override the default scheduler task selection mechanism
1781 with implementations that make use of architecture specific instructions.
1782 + Added ability to suppress tick interrupts during idle time, and in so
1783 doing, provide the ability to make use of architecture specific low power
1785 + Added the portSUPPRESS_TICKS_AND_SLEEP() macro and vTaskStepTick() helper
1787 + Added the configSYSTICK_CLOCK_HZ configuration constant.
1788 + Reworked the Cortex-M3 and Cortex-M4F port layers for GCC, Keil and IAR to
1789 directly support basic power saving functionality.
1790 + Added hooks to allow basic power saving to be augmented in the application
1791 by making use of chip specific functionality.
1792 + Minor change to allow mutex type semaphores to be used from interrupts
1793 (which would not be a normal usage model for a mutex).
1794 + Change the behaviour of the interrupt safe interrupt mask save and restore
1795 macros in the Cortex-M ports. The save macro now returns the previous
1796 mask value. The restore macro now uses the previous mask value. These
1797 changes are not necessary for the kernel's own implementation, and are
1798 made purely because the macros were being used by application writers.
1799 + Added eTaskStateGet() API function.
1800 + Added port specific optimisations to the PIC32 port layer, and updated the
1801 PIC32 demo applications to make use of this new feature.
1802 + Added port specific optimisations to the Win32 simulator port.
1803 + Added new ports and demo applications for the TI Hercules RM48 and TMS570
1804 safety microcontrollers.
1805 + Added SAM3 demos targeting the ATSAM3S-EK2 and ATSAM3X-EK evaluation
1807 + Updated the PIC32 MPLAB X project to manually set the compiler include
1808 paths instead of using the IDE entry box following reports that the
1809 include paths were somehow being deleted.
1810 + Improved character handling in FreeRTOS+CLI.
1812 Changes between V7.1.1 and V7.2.0 released 14 August 2012
1814 FreeRTOS V7.2.0 is backward compatible with FreeRTOS V7.1.2.
1816 + Added a FreeRTOS+ sub-directory. The directory contains some FreeRTOS+
1817 source code, and example projects that use the FreeRTOS Win32 simulator.
1818 + Added a new example heap allocation implementation (heap_4.c) that
1819 includes memory block coalescence.
1820 + Added a demo that targets the Atmel SAM4S Cortex-M4 based microcontroller.
1821 The demo is preconfigured to build using the free Atmel Studio 6 IDE and
1823 + Added xSemaphoreTakeFromISR() implementation.
1824 + The last parameter in ISR safe FreeRTOS queue and semaphore functions
1825 (xHigherPriorityTaskWoken) is now optional and can be set to NULL if it
1827 + Update the IAR and MSP430X ports to clear all lower power mode bits before
1828 exiting the tick interrupt [bug fix].
1829 + Allow xQueueReset() to be used, even when the queues event lists are not
1831 + Added a vQueueDelete() handler for the FreeRTOS MPU port (this was
1832 previously missing).
1833 + Updated the vPortSVCHandler() functions in the FreeRTOS MPU port layer to
1834 ensure it compiles with the latest ARM GCC compilers from Linaro.
1835 + Updated the prvReadGP() function in the NIOS II port to ensure the compiler
1836 can choose any register for the functions parameter (required at high
1837 compiler optimisation levels).
1838 + Add #error macros into the Keil and IAR Cortex-M ports to ensure they
1839 cannot be built if the user has set configMAX_SYSCALL_INTERRUPT_PRIORITY
1841 + Added comments in the FreeRTOSConfig.h files associated with Cortex-M3 and
1842 Cortex-M4 demos stating that the configMAX_SYSCALL_INTERRUPT_PRIORITY
1843 parameter must not be set to 0.
1844 + Introduce new INCLUDE_xQueueGetMutexHolder configuration constant
1846 + Added two new list handling macros - for internal use only in upcoming new
1848 + Removed all mention of the legacy vTaskStartTrace and ulTaskEndTrace
1849 macros. FreeRTOS+Trace supersedes the legacy trace.
1850 + Added a configASSERT() into the vPortFree() function in heap_1.c as it is
1851 invalid for the function to be called.
1852 + Made the xRxLock and xTxLock members of the queue structure volatile.
1853 This is probably not necessary, and is included as a precautionary
1855 + Modify the assert() that checks to see if the priority passed into an
1856 xTaskCreate() function is within valid bounds to permit the assert to be
1857 used in the FreeRTOS MPU port.
1858 + The software timer service (daemon) task is now created in a way that
1859 to ensure compatibility with FreeRTOS MPU.
1861 Changes between V7.1.0 and V7.1.1 released May 1 2012
1865 The following ports are brand new:
1868 The following ports have been available as separate downloads for a number
1869 of months, but are now included in the main FreeRTOS download.
1872 + Cortex-M4F GCC (with full floating point support)
1877 The following demos are brand new:
1878 + Renesas RX63N RDK (Renesas compiler)
1880 The following demos have been available as separate downloads for a number
1881 of months, but are now included in the main FreeRTOS download.
1882 + NXP LPC1114 GCC/LPCXpresso
1884 + Infineon XMC4500 GCC/Atollic
1885 + Infineon XMC4500 IAR
1886 + Infineon XMC4500 Keil
1887 + Infineon XMC4500 Tasking
1890 Kernel miscellaneous / maintenance:
1892 + Introduced the portSETUP_TCB() macro to remove the requirement for the
1893 Windows simulator to use the traceTASK_CREATE() macro, leaving the trace
1894 macro available for use by FreeRTOS+Trace (https://www.FreeRTOS.org/trace).
1895 + Added a new trace macro, traceMOVE_TASK_TO_READY_STATE(), to allow future
1896 FreeRTOS+Trace versions to provide even more information to users.
1897 + Updated the FreeRTOS MPU port to be correct for changes that were
1898 introduced in FreeRTOS V7.1.0.
1899 + Introduced the xQueueReset() API function.
1900 + Introduced the xSemaphoreGetMutexHolder() API function.
1901 + Tidy up various port implementations to add the static key word where
1902 appropriate, and remove obsolete code.
1903 + Slight change to the initial stack frame given to the RX600 ports to allow
1904 them to be used in the Eclipse based E2Studio IDE without confusing GDB.
1905 + Correct the alignment given to the initial stack of Cortex-M4F tasks.
1906 + Added a NOP following each DINT instruction on MSP430 devices for strict
1907 conformance with the instructions on using DINT.
1908 + Changed the implementation of thread deletes in the Win32 port to prevent
1909 the port making use of the traceTASK_DELETE() trace macros - leaving this
1910 macro free for use by FreeRTOS+Trace.
1911 + Made some benign changes to the RX600 Renesas compiler port layer to
1912 ensure the code can be built to a library without essential code being
1913 removed by the linker.
1914 + Reverted the change in the name of the uxTaskNumber variable made in
1915 V7.1.0 as it broke the IAR plug-in.
1918 Demo miscellaneous / maintenance:
1920 + The command interpreter has now been formally released as FreeRTOS+CLI,
1921 and been moved out of the main FreeRTOS download, to instead be available
1922 from the FreeRTOS+ Ecosystem site https://www.FreeRTOS.org/plus.
1923 + flash_timer.c/h has been added to the list of standard demo tasks. This
1924 performs the same functionality as the flash.c tasks, but using software
1925 timers in place of tasks.
1926 + Upgraded the PIC32 demo as follows: Changes to how the library functions
1927 are called necessitated by the new compiler version, addition of MPLAB X
1928 project with PIC32MX360, PIC32MX460 and PIC32MX795 configurations,
1929 addition of simply blinky demo, updated FreeRTOSConfig.h to include more
1930 parameters, addition of hook function stubs.
1931 + The MSP430X IAR and CCS demos have been updated to ensure the power
1932 settings are correct for the configured CPU frequency.
1933 + Rowley CrossWorks projects have been updated to correct the "multiple
1934 definition of ..." warnings introduced when the toolchain was updated.
1935 + Updated various FreeRTOSConfig.h header files associated with projects
1936 that build with Eclipse to include a #error statement informing the user
1937 that the CreateProjectDirectoryStructure.bat batch file needs to be
1938 executed before the projects can be opened.
1939 + Renamed directories that included "CCS4" in their name to remove the '4'
1940 and instead just be "CCS". This is because the demo was updated and
1941 tested to also work with later Code Composer Studio versions.
1942 + Updated the TCP/IP periodic timer frequency in numerous uIP demos to be
1943 50ms instead of 500ms.
1945 Changes between V7.0.2 and V7.1.0 released December 13 2011
1949 + Cortex-M4F IAR port.
1950 + Cortex-M4F Keil/RVDS port.
1955 + NXP LPC4350 using the Keil MDK, and demonstrated on a Hitex development
1957 + ST STM32F407 using the IAR Embedded Workbench for ARM, and demonstrated on
1958 the IAR STM32F407ZG-SK starter kit.
1959 + Infineon TriCore TC1782, using the GCC compiler, demonstrated on the
1960 TriBoard TC1782 evaluation board.
1961 + Renesas RX630, using the Renesas compiler and HEW, demonstrated on an
1962 RX630 RSK (Renesas Starter Kit).
1964 Miscellaneous / maintenance:
1966 + Removed all calls to printf() from the K60/IAR Kinetis demo so the project
1967 can execute stand alone - without being connected to the debugger.
1968 + Completed the command interpreter framework. Command handlers now receive
1969 the entire command string, giving them direct access to parameters.
1970 Utility functions are provided to check the number of parameters, and
1971 return parameter sub-strings.
1972 + The previously documented fix for the bug in xTaskResumeFromISR() that
1973 effected (only) ports supporting interrupt nesting has now been
1974 incorporated into the main release.
1975 + The portALIGNMENT_ASSERT_pxCurrentTCB() definition has been added to allow
1976 specific ports to skip the second stack alignment check when a task is
1977 created. This is because the second check is not appropriate for some
1978 ports - including the new TriCore port where the checked pointer does not
1979 actually point to a stack.
1980 + The portCLEAN_UP_TCB() macro has been added to allow port specific clean
1981 up when a task is deleted - again this is required by the TriCore port.
1982 + Various other minor changes to ensure warning free builds on a growing
1983 number of microcontroller and toolchain platforms. This includes a
1984 (benign) correction to the prototype of the
1985 vApplicationStackOverflowHook() definition found in lots of recent demos.
1989 + The legacy trace mechanism has been completely removed - it has been
1990 obsolete for the years since the trace macros were introduced. The
1991 configuration constant configUSE_TRACE_FACILITY is now used to optionally
1992 include additional queue and task information. The additional information
1993 is intended to make the trace mechanism more generic, and allow the trace
1994 output to provide more information. When configUSE_TRACE_FACILITY is set
1996 - the queue structure includes an additional member to hold the queue
1997 type, which can be base, mutex, counting semaphore, binary semaphore
1999 - the queue structure includes an additional member to hold a queue
2000 number. A trace tool can set and query the queue number for its own
2001 purposes. The kernel does not use the queue number itself.
2002 - the TCB structure includes an additional member to hold a task number
2003 number. A trace tool can set and query the task number for its own
2004 purposes. The kernel does not use the task number itself.
2005 + Queues and all types of semaphores are now automatically allocated their
2006 type as they are created.
2007 + Added two new trace macros - traceTASK_PRIORITY_INHERIT() and
2008 traskTASK_PRIORITY_DISINHERIT().
2009 + Updated the traceQUEUE_CREATE_FAILED() macro to take a parameter that
2010 indicates the type of queue, mutex, or semaphore that failed to be
2012 + The position from which traceCREATE_MUTEX() is called has been moved from
2013 after the call to xQueueGenericSend() [within the same function] to before
2014 the call. This ensures the trace events occur in the correct order.
2015 + The value passed into tracePRIORITY_SET() has been corrected for the case
2016 where vTaskPrioritySet() is called with a null parameter.
2018 Changes between V7.0.1 and V7.0.2 released September 20 2011
2022 + The official FreeRTOS Renesas RX200 port and demo application have been
2023 incorporated into the main FreeRTOS zip file download.
2024 + The official FreeRTOS Renesas RL78 port and demo application have been
2025 incorporated into the main FreeRTOS zip file download.
2026 + The official FreeRTOS Freescale Kinetis K60 tower demo application has
2027 been incorporated into the main FreeRTOS zip file download. This includes
2028 an embedded web server example.
2029 + A new Microblaze V8 port layer has been created to replace the older, now
2030 deprecated, port layer. The V8 port supports V8.x of the Microblaze IP,
2031 including exceptions, caches, and the floating point unit. A new
2032 Microblaze demo has also been added to demonstrate the new Microblaze V8
2033 port layer. The demo application was created using V13.1 of the Xilinx
2034 EDK, and includes a basic embedded web server that uses lwIP V1.4.0.
2035 + The official FreeRTOS Fujitsu FM3 MB9A310 demo application has been
2036 incorporated into the main FreeRTOS zip file download. Projects are
2037 provided for both the IAR and Keil toolchains.
2042 + xTaskGetIdleTaskHandle() has been added.
2043 + xTaskGetTimerDaemonTaskHandle() has been added.
2044 + pcTaskGetTaskName() has been added.
2045 + vSemaphoreDelete() macro has been added to make it obvious how to delete
2046 a semaphore. In previous versions vQueueDelete() had to be used.
2047 + vTaskCleanUpResources() has been removed. It has been obsolete for a
2049 + portPOINTER_SIZE_TYPE has been introduced to prevent compiler warnings
2050 being generated when the size of a pointer does not match the size of
2051 the stack type. This will (has already) be used in new ports, but will
2052 not be retrofitted to existing ports until the existing port itself is
2055 Other updates and news:
2057 + The core files have all been modified to tighten the coding standard even
2058 further. These are style, not functional changes.
2059 + All ARM7 port layers have been slightly modified to prevent erroneous
2060 assert() failures when tasks are created and configASSERT() is defined.
2061 + All ARM IAR projects have been updated to build with the latest V6.2.x
2062 versions of the IAR Embedded Workbench for ARM tools (EWARM). This was
2063 necessary due to a change in the way EWARM uses the CMSIS libraries.
2064 + The PIC32 port layer has been updated in preparation for V2 of the C32
2066 + The old Virtex-4 Microblaze demo has been marked as deprecated. Please
2067 use the brand new Spartan-6 port and demo in its place.
2068 + The bones of a new generic command interpreter is located in
2069 FreeRTOS/Demo/Common/Utils/CommandInterpreter.c. This is still a work in
2070 progress, and not documented. It is however already in use. It will be
2071 documented in full when the projects that are already using it are
2073 + A couple of new standard demos have been included. First, a version of
2074 flop.c called sp_flop.c. This is similar to flop.c, but uses single
2075 precision floats in place of double precision doubles. This allows the
2076 for testing ports to processors that have only single precision floating
2077 point units, and revert to using emulated calculations whenever a double
2078 is used. Second, comtest_strings.c has been included to allow the test
2079 of UART drivers when an entire string is transmitted at once. The
2080 previous comtest.c only used single character transmission and reception.
2081 + lwIP V1.4.0 is now included in the FreeRTOS/Demo/Common directory, and
2082 used by a couple of new demos.
2084 Changes between V7.0.0 and V7.0.1 released May 13 2011
2086 + Added a Fujitsu FM3 demo application for both the IAR and Keil tool
2088 + Added a SmartFusion demo application for all of the IAR, Keil and
2089 SoftConsole (GCC/Eclipse) tool chains.
2090 + Updated the RX600 port and demo applications to take into account the
2091 different semantics required when using the latest (V1.0.2.0) version of
2092 the Renesas compiler.
2093 + Modified the RX600 Ethernet driver slightly to make it more robust under
2094 heavy load, and updated the uIP handling task to make use of the FreeRTOS
2096 + Slightly changed the PIC32 port layer to move an ehb instruction in line
2097 with the recommendations of the MIPS core manual, and ensure 8 byte stack
2098 alignment is truly always obtained.
2099 + Changed the behaviour when tasks are suspended before the scheduler has
2100 been started. Before, there needed to be at least one task that was not
2101 in the suspended state. This is no longer the case.
2103 Changes between V6.1.1 and V7.0.0 released April 8 2011
2105 FreeRTOS V7.0.0 is backward compatible with FreeRTOS V6.x.x
2109 + Introduced a new software timer implementation.
2110 + Introduced a new common demo application file to exercise the new timer
2112 + Updated the Win32/MSVC simulator project to include the new software timer
2113 demo tasks and software timer tick hook test. Much simpler software timer
2114 demonstrations are included in the demo projects for both of the new ports
2115 (MSP430X with CCS4 and STM32 with TrueStudio).
2116 + Various enhancements to the kernel implementation in tasks.c. These are
2117 transparent to users and do not effect the pre-existing API.
2118 + Added calls to configASSERT() within the kernel code. configASSERT() is
2119 functionally equivalent to the standard C assert() macro, but does not
2120 rely on the compiler providing assert.h.
2124 + Updated the MSP430X IAR port and demo project to include support for the
2125 medium memory model.
2126 + Added a demo project for the MSP430X that targets the MSP430X Discovery
2127 board and uses the Code Composer Studio 4 tools. This demo includes use
2128 of the new software timer implementation.
2129 + Added an STM32F100RB demo project that targets the STM32 Discovery Board
2130 and uses the TrueStudio Eclipse based IDE from Atollic.
2131 + Removed some compiler warnings from the PSoC demo application.
2132 + Updated the PIC32 port layer to ensure the
2133 configMAX_SYSCALL_INTERRUPT_PRIORITY constant works as expected no matter
2134 what its value is (within the valid range set by the microcontroller
2136 + Updated the PIC24, dsPIC and PIC32 projects so they work with the latest
2137 MPLAB compiler versions from Microchip.
2138 + Various cosmetic changes to prepare for a standards compliance statement
2139 that will be published after the software release.
2142 Changes between V6.1.0 and V6.1.1 released January 14 2011
2144 + Added two new Windows simulator ports. One uses the free Microsoft Visual
2145 Studio 2010 express edition, and the other the free MingW/Eclipse
2146 environment. Demo projects are provided for both.
2147 + Added three demo projects for the PSoC 5 (CYAC5588). These are for the
2148 GCC, Keil, and RVDS build tools, and all use the PSoC Creator IDE.
2149 + Added a demo for the low power STM32L152 microcontroller using the IAR
2151 + Added a new port for the MSP430X core using the IAR Embedded Workbench.
2152 + Updated all the RX62N demo projects that target the Renesas Demonstration
2153 Kit (RDK) to take into account the reversed LED wiring on later hardware
2154 revisions, and the new J-Link debug interface DLL.
2155 + Updated all the RX62N demo projects so the IO page served by the example
2156 embedded web server works with all web browsers.
2157 + Updated the Red Suite projects to work with the up coming Red Suite
2158 release, and to use a more recent version of the CMSIS libraries.
2159 + Added the traceTAKE_MUTEX_RECURSIVE_FAILED() trace macro.
2160 + Removed the (pointless) parameter from the traceTASK_CREATE_FAILED()
2162 + Introduced the portALT_GET_RUN_TIME_COUNTER_VALUE() macro to compliment
2163 the already existing portGET_RUN_TIME_COUNTER_VALUE(). This allows for
2164 more flexibility in how the time base for the run time statistics feature
2166 + Added a "cpsie i" instruction before the "svc 0" instruction used to start
2167 the scheduler in each of the Cortex M3 ports. This is to ensure that
2168 interrupts are globally enabled prior to the "svc 0" instruction being
2169 executed in cases where interrupts are left disabled by the C start up
2171 + Slight optimisation in the run time stats calculation.
2173 Changes between V6.0.5 and V6.1.0 released October 6 2010
2175 + Added xTaskGetTickCountFromISR() function.
2176 + Modified vTaskSuspend() to allow tasks that have just been created to be
2177 immediately suspended even when the kernel has not been started. This
2178 allows them to effectively start in the Suspended state - a feature that
2179 has been asked for on numerous occasions to assist with initialisation
2181 + Added ports for the Renesas RX62N using IAR, GCC and Renesas tool suites.
2182 + Added a STM32F103 demo application that uses the Rowley tools.
2183 + Under specific conditions xFreeBytesRemaining within heap_2.c could end up
2184 with an incorrect value. This has been fixed.
2185 + xTaskCreateGeneric() has a parameter that can be used to pass the handle
2186 of the task just created out to the calling task. The assignment to this
2187 parameter has been moved to ensure it is assigned prior to the newly
2188 created having any possibility of executing. This takes into account the
2189 case where the assignment is made to a global variable that is accessed by
2190 the newly created task.
2191 + Fixed some build time compiler warnings in various FreeTCPIP (based on
2193 + Fixed some build time compiler warnings in Demo/Common/Minimal/IntQueue.c.
2195 Changes between V6.0.4 and V6.0.5 released May 17 2010
2197 + Added port and demo application for the Cortus APS3 processor.
2199 Changes between V6.0.3 and V6.0.4 released March 14 2010
2201 + All the contributed files that were located in the Demo/Unsupported_Demos
2202 directory have been removed. These files are instead now available in the
2203 new Community Contributions section of the FreeRTOS website. See
2204 https://www.FreeRTOS.org/RTOS-contributed-ports.html
2205 + The project file located in the Demo/CORTEX_STM32F107_GCC_Rowley directory
2206 has been upgraded to use V2.x of the Rowley Crossworks STM32 support
2208 + An initial Energy Micro EFM32 demo has been included. This will be
2209 updated over the coming months to make better use of the low power modes
2212 Changes between V6.0.2 and V6.0.3 released February 26 2010
2214 + SuperH SH7216 (SH2A-FPU) port and demo application added.
2215 + Slight modification made to the default implementation of
2216 pvPortMallocAligned() and vPortFreeAligned() macros so by default they
2217 just call pvPortMalloc() and vPortFree(). The macros are only needed to
2218 be defined when a memory protection unit (MPU) is being used - and then
2219 only depending on other configuration settings.
2221 Changes between V6.0.1 and V6.0.2 released January 9th 2010
2223 + Changed all GCC ARM 7 ports to use 0 as the SWI instruction parameter.
2224 Previously the parameter was blank and therefore only an implicit 0 but
2225 newer GCC releases do not permit this.
2226 + Updated IAR SAM7S and SAM7X ports to work with IAR V5.40.
2227 + Changed the stack alignment requirement for PIC32 from 4 bytes to 8 bytes.
2228 + Updated prvListTaskWithinSingleList() is it works on processors where the
2229 stack grows up from low memory.
2230 + Corrected some comments.
2231 + Updated the startup file for the RVDS LPC21xx demo.
2233 Changes between V6.0.0 and V6.0.1 released November 15th 2009
2235 + Altered pxPortInitialiseStack() for all Cortex-M3 ports to ensure the
2236 stack pointer is where the compiler expects it to be when a task first
2239 The following minor changes only effect the Cortex-M3 MPU port:
2241 + portRESET_PRIVILEGE() assembly macro updated to include a clobber list.
2242 + Added prototypes for all the privileged function wrappers to ensure no
2243 compile time warnings are generated no matter what the warning level
2245 + Corrected the name of portSVC_prvRaisePrivilege to
2246 portSVC_RAISE_PRIVILEGE.
2247 + Added conditional compilation into xTaskGenericCreate() to prevent some
2248 compilers issuing warnings when portPRIVILEGE_BIT is defined as zero.
2251 Changes between V5.4.2 and V6.0.0 released October 16th 2009
2253 FreeRTOS V6 is backward compatible with FreeRTOS V5.x.
2257 + FreeRTOS V6 is the first version to include memory protection unit (MPU)
2258 support. Two ports now exist for the Cortex M3, the standard FreeRTOS
2259 which does not include MPU support, and FreeRTOS-MPU which does.
2260 + xTaskCreateRestricted() and vTaskAllocateMPURegions() API functions added
2261 in support of FreeRTOS-MPU.
2262 + Wording for the GPL exception has been (hopefully) clarified. Also the
2263 license.txt file included in the download has been fixed (the previous
2264 version contained some corruption).
2268 + New API function xPortGetFreeHeapSize() added to heap_1.c and heap_2.c.
2269 + ARM7 GCC demo interrupt service routines wrappers have been modified to
2270 call the C portion using an __asm statement. This prevents the function
2271 call being inlined at higher optimisation levels.
2272 + ARM7 ports now automatically set the THUMB bit if necessary when
2273 setting up the initial stack of a task - removing the need for
2274 THUMB_INTERWORK to be defined. This also allows THUMB mode and ARM mode
2275 tasks to be mixed more easily.
2276 + All ARM7/9 ports now have portBYTE_ALIGNMENT set to 8 by default.
2277 + Various demo application project files have been updated to be up to date
2278 with the latest IDE versions.
2279 + The linker scripts used with command line GCC demos have been updated to
2280 include an eh_frame section to allow their use with the latest Yagarto
2281 release. Likewise the demo makefiles have been updated to include
2282 command line options to reduce or eliminate the eh_frame section all
2284 + The definition of portBYTE_ALIGNMENT_MASK has been moved out of the
2285 various memory allocation files and into the common portable.h header
2287 + Removed unnecessary use of portLONG, portSHORT and portCHAR.
2288 + Added LM3Sxxxx demo for Rowley CrossWorks.
2289 + Posix simulator has been upgraded - see the corresponding WEB page on the
2293 Changes between V5.4.1 and V5.4.2 released August 9th 2009
2295 + Added a new port and demo app for the Altera Nios2 soft core.
2296 + Added LPC1768 demo for IAR.
2297 + Added a USB CDC demo to all LPC1768 demos (Code Red, CrossWorks and IAR).
2298 + Changed clock frequency of LPC1768 demos to 99MHz.
2300 Changes between V5.4.0 and V5.4.1 released July 25th 2009
2302 + New hook function added. vApplicationMallocFailedHook() is (optionally)
2303 called if pvPortMalloc() returns NULL.
2304 + Additional casting added to xTaskCheckForTimeOut(). This prevents
2305 problems that can arise should configUSE_16_BIT_TICKS be set to 1 on a
2306 32 bit architecture (which would probably be a mistake, anyway).
2307 + Corrected the parameter passed to NVIC_SetPriority() to set the MAC
2308 interrupt priority in both LPC1768 demos.
2309 + Decreased the default setting of configMINIMAL_STACK_SIZE in the PIC32
2310 demo application to ensure the heap space was not completely consumed
2311 before the scheduler was started.
2313 Changes between V5.3.1 and V5.4.0 released July 13th 2009
2315 + Added Virtex5 / PPC440 port and demos.
2316 + Replaced the LPC1766 Red Suite demo with an LPC1768 Red Suite demo. The
2317 original demo was configured to use engineering samples of the CPU. The
2318 new demo has an improved Ethernet driver.
2319 + Added LPC1768 Rowley demo with zero copy Ethernet driver.
2320 + Reworked byte alignment code to ensure 8 byte alignment works correctly.
2321 + Set configUSE_16_BIT_TICKS to 0 in the PPC405 demo projects.
2322 + Changed the initial stack setup for the PPC405 to ensure the small data
2323 area pointers are setup correctly.
2325 Changes between V5.3.0 and V5.3.1 released June 21st 2009
2327 + Added ColdFire V1 MCF51CN128 port and WEB server demo.
2328 + Added STM32 Connectivity Line STM32107 Cortex M3 WEB server demo.
2329 + Changed the Cortex M3 port.c asm statements to __asm so it can be
2330 compiled using Rowley CrossWorks V2 in its default configuration.
2331 + Updated the Posix/Linux simulator contributed port.
2333 Changes between V5.2.0 and V5.3.0 released June 1st 2009
2337 + Added new (optional) feature that gathers statistics on the amount of CPU
2338 time used by each task.
2339 + Added a new demo application for the Atmel AT91SAM3U Cortex-M3 based
2341 + Added a new demo application for the NXP LPC1766 Cortex-M3 based
2343 + Added a contributed port/demo that allows FreeRTOS to be 'simulated' in a
2347 + Updated the Stellaris uIP WEB server demos to include the new run time
2348 statistics gathering feature - and include a served WEB page that
2349 presents the information in a tabular format.
2350 + Added in the lwIP port layer for the Coldfire MCF52259.
2351 + Updated the CrossWorks LPC2368 WEB server to include an image in the
2353 + Changed some of the timing in the initialisation of the LPC2368 MAC to
2354 permit its use on all part revisions.
2355 + Minor modifications to the core uIP code to remove some compiler warnings.
2356 + Added xTaskGetApplicationTaskTag() function and updated the OpenWatcom
2357 demo to make use of the new function.
2358 + Added contributed demos for AVR32 AP7000, STM32 Primer 2 and STM32 using
2360 + Heap_1.c and Heap_2.c used to define structures for the purpose of data
2361 alignment. These have been converted to unions to save a few bytes of
2362 RAM that would otherwise be wasted.
2363 + Remove the call to strncpy() used to copy the task name into the TCB when
2364 the maximum task name is configured to be 1 byte long.
2366 Changes between V5.1.2 and V5.2.0 released March 14th 2009
2368 + Optimised the queue send and receive functions (also used by semaphores).
2369 + Replaced the standard critical sections used to protect BIOS calls in the
2370 PC port to instead use scheduler locks. This is because the BIOS calls
2371 always return with interrupts enabled.
2372 + Corrected unclosed comments in boot.s.
2374 Changes between V5.1.1 and V5.1.2 released February 9th 2009
2376 + Added NEC V850ES port and demo.
2377 + Added NEC 78K0R port and demo.
2378 + Added MCF52259 port and demo.
2379 + Added the AT91SAM9XE port and demo.
2380 + Updated the MCF52233 FEC driver to work around a silicon bug that
2381 prevents the part auto negotiating some network parameters.
2382 + Minor modifications to the MCF52233 makefile to permit it to be used
2384 + Updated the STM32 primer files to allow them to be built with the latest
2385 version of the RIDE tools.
2386 + Updated the threads.js Java script used for kernel aware debugging in
2387 the Rowley CrossWorks IDE.
2390 Changes between V5.1.0 and V5.1.1 released November 20, 2008
2392 + Added Coldfire MCF52233 WEB server demo using GCC and Eclipse.
2393 + Added IAR MSP430 port and demo.
2394 + Corrected several compiler time issues that had crept in as tool versions
2396 + Included FreeRTOS-uIP - a faster uIP. This is not yet complete.
2398 Changes between V5.0.4 and V5.1.0 released October 24, 2008
2400 + Added a new port and demo application for the ColdFire V2 core using the
2401 CodeWarrior development tools.
2402 + Replaced the ARM7 demo that used the old (and now no longer supported)
2403 Keil compiler with a new port that uses the new Keil/RVDS combo.
2404 + Stack overflow checking now works for stacks that grow up from low
2405 memory (PIC24 and dsPIC).
2406 + BUG FIX - set the PIC32 definition of portSTACK_GROWTH to the correct
2408 + MSP430 port layers have been updated to permit tasks to place the
2409 microcontroller into power down modes 1 to 3. The demo applications have
2410 likewise been updated to demonstrate the new feature.
2411 + Replaced the two separate MSP430/Rowley port layers with a single and more
2413 + Added more contributed ports, including ports for NEC and SAM9
2415 + Changed the linker script used in the LPC2368 Eclipse demo.
2417 Changes between V5.0.3 and V5.0.4 released September 22, 2008
2419 + Completely re-written port for ColdFire GCC.
2420 + Bug fix: All Cortex M3 ports have a minor change to the code that sets
2421 the pending interrupt.
2422 + Some header files require that FreeRTOS.h be included prior to their
2423 inclusion. #error message have been added to all such header file
2424 informing users to the cause of the compilation error should the headers
2425 not be included in the correct order.
2427 Changes between V5.0.2 and V5.0.3 released July 31, 2008
2429 Changes relating to the Cortex M3:
2431 + Added configMAX_SYSCALL_INTERRUPT_PRIORITY usage to all the Cortex M3
2432 ports and demos. See the port documentation pages on the FreeRTOS.org
2433 WEB site for full usage information.
2434 + Improved efficiency of Cortex M3 port even further.
2435 + Ensure the Cortex M3 port works no matter where the vector table is
2437 + Added the IntQTimer demo/test tasks to a demo project for each CM3 port
2438 (Keil, GCC and IAR) to test the new configMAX_SYSCALL_INTERRUPT_PRIORITY
2440 + Added the mainINCLUDE_WEB_SERVER definition to the LM3SXXXX IAR and Keil
2441 projects to allow the WEB server to be conditionally excluded from the
2442 build and therefore allow use of the KickStart (code size limited)
2447 + Moved the PIC24 and dsPIC versions of vPortYield() from the C file to
2448 an assembly file to allow use with all MPLAB compiler versions. This also
2449 allows the omit-frame-pointer optimisation to be turned off.
2451 Changes between V5.0.0 and V5.0.2 released May 30, 2008
2453 + Updated the PIC32 port to allow queue API calls to be used from
2454 interrupts above the kernel interrupt priority, and to allow full
2455 interrupt nesting. Task stack usages has also been reduced.
2456 + Added a new PowerPC port that demonstrates how the trace macros can be
2457 used to allow the use of a floating point co-processor. The
2458 traceTASK_SWITCHED_OUT() and traceTASK_SWITCHED_INT() macros are used to
2459 save and restore the floating point context respectively for those tasks
2460 that actually use floating point operations.
2461 + BUG FIX: The first PPC405 port contained a bug in that it did not leave
2462 adequate space above the stack for the backchain to be saved when a task
2463 started to execute for the first time.
2464 + Updated queue.c to add in the means to allow interrupt nesting and for
2465 queue API functions to be called from interrupts that have a priority
2466 above the kernel priority. This is only supported on PIC32 ports thus
2468 + Fixed the compiler warnings that were generated when the latest version
2470 + Remove all inline usage of 'inline' from the core kernel code.
2471 + Added the queue registry feature. The queue registry is provided as a
2472 means for kernel aware debuggers to locate queue definitions. It has no
2473 purpose unless you are using a kernel aware debugger. The queue registry
2474 will only be used when configQUEUE_REGISTRY_SIZE is greater than zero.
2475 + Added the ST Cortex-M3 drivers into the Demo/Common/Drivers directory to
2476 prevent them from having to be included in multiple demos.
2477 + Added a Keil STM32 demo application.
2478 + Changed the blocktim.c test files as it is no longer legitimate for all
2479 ports to call queue API functions from within a critical section.
2480 + Added the IntQueue.c test file to test the calling of queue API functions
2481 from different interrupt priority levels, and test interrupt nesting.
2483 Changes between V5.0.0 and V5.0.1
2485 + V5.0.1 was a customer specific release.
2487 Changes between V4.8.0 and V5.0.0 released April 15, 2008
2489 *** VERY IMPORTANT INFORMATION ON UPGRADING TO FREERTOS.ORG V5.0.0 ***
2491 The parameters to the functions xQueueSendFromISR(), xQueueSendToFrontFromISR(),
2492 xQueueSendToBackFromISR() and xSemaphoreGiveFromISR() have changed. You must
2493 update all calls to these functions to use the new calling convention! Your
2494 compiler might not issue any type mismatch warnings!
2499 + Support added for the new Luminary Micro LM3S3768 and LM3S3748 Cortex-M3
2501 + New task hook feature added.
2502 + PowerPC demo updated to use version 10.1 of the Xilinx EDK.
2503 + Efficiency gains within the PIC32 port layer.
2505 Changes between V4.7.2 and V4.8.0 released March 26 2008
2507 + Added a Virtex4 PowerPC 405 port and demo application.
2508 + Added optional stack overflow checking and new
2509 uxTaskGetStackHighWaterMark() function.
2510 + Added new xQueueIsQueueEmptyFromISR(), xQueueIsQueueFullFromISR() and
2511 uxQueueMessagesWaitingFromISR() API functions.
2512 + Efficiency improvements to the Cortex-M3 port layer. NOTE: This
2513 requires that an SVC handler be installed in the application.
2514 + Efficiency improvements to the queue send and receive functions.
2515 + Added new trace macros. These are application definable to provide
2516 a flexible trace facility.
2517 + Implemented the configKERNEL_INTERRUPT_PRIORITY within the Keil Cortex
2518 M3 port layer (bringing it up to the same standard as the IAR and GCC
2520 + Ports that used the arm-stellaris-eabi-gcc tools have been converted to
2521 use the arm-non-eabi-gcc tools.
2523 Changes between V4.7.1 and V4.7.2 released February 21, 2008
2525 + Added Fujitsu MB91460 port and demo.
2526 + Added Fujitsu MB96340 port and demo.
2527 + Tidied up the capitalisation of include files to facilitate builds on
2529 + Removed some redundant casting that was generating warnings - but was
2530 included to remove warnings on other compilers.
2532 Changes between V4.7.0 and V4.7.1 released February 3, 2008
2534 + Updated all IAR ARM projects to use V5.11 of the IAR Embedded Workbench
2536 + Introduced recursive semaphore feature.
2537 + Updated LPC2368 demos to take into account silicon bugs in old chip
2539 + Updated STR9 uIP port to manually set the net mask and gateway addresses.
2540 + Updating demos to allow more to run with the co-operative scheduler.
2541 + Fixed co-operative scheduler behaviour upon the occurrence of a tick
2542 interrupt while the scheduler was suspended.
2543 + Updated documentation contained within semphr.h.
2544 + ARM7 GCC ports no longer use the IRQ attribute.
2546 Changes between V4.6.1 and V4.7.0 released December 6, 2007
2548 + Introduced the counting semaphore macros and demo source files. The
2549 Open Watcom PC project has been updated to include the new demo. See
2550 the online documentation for more information.
2551 + Introduced the 'alternative' queue handling API and demo source files.
2552 The Open Watcom PC project has been updated to include the new demo
2553 source files. See the online documentation for more information.
2554 + Added AT91SAM7X Eclipse demo project.
2555 + Added the STM32 primer demo project for the GCC compiler and Ride IDE.
2556 + Removed the .lock files that were mistakenly included in the V4.6.1
2559 Changes between V4.6.0 and V4.6.1 released November 5 2007
2561 + Added support for the MIPS M4K based PIC32.
2562 + Added 'extern "C"' to all the header files to facilitate use with C++.
2564 Changes between V4.5.0 and V4.6.0 released October 28 2007
2566 + Changed the method used to force a context switch within an ISR for the
2567 ARM7/9 GCC ports only. The portENTER_SWITCHING_ISR() and
2568 portEXIT_SWITCHING_ISR() macros are no longer supported. This is to
2569 ensure correct behaviour no matter which GCC version is used, with or
2570 without the -fomit-frame-pointer option, and at all optimisation levels.
2571 + Corrected the prototype for xQueueGenericSend() within queue.h.
2573 Changes between V4.4.0 and V4.5.0 released September 17 2007
2575 + Added the xQueueSendToFront(), xQueueSendToBack() and xQueuePeek()
2576 functionality. These should now be used in preference to the old
2577 xQueueSend() function - which is maintained for backward compatibility.
2578 + Added Mutex functionality. The behaviour of mutexes is subtly different
2579 to the already existing binary semaphores as mutexes automatically
2580 include a priority inheritance mechanism.
2581 + Added the GenQTest.c and QPeek.c to test and demonstrate the behaviour
2582 of the new functionality.
2583 + Updated the LM3Sxxxx and PC ports to include the new GenQTest.c and
2585 + Updated the GCC port for the Cortex M3 to include the
2586 configKERNEL_INTERRUPT_PRIORITY functionality. This was previously only
2587 included in the IAR port.
2588 + Optimised the GCC and IAR port layer code - specifically the context
2590 + Consolidated the LM3Sxxxx EK demos for all development tools into a
2591 single project that automatically detects which version of the EK the
2592 application is executing on.
2593 + Added Eclipse support for LM3Sxxxx evaluation kits.
2594 + Added Eclipse support for the Keil LPC2368 evaluation kit.
2595 + Added the Demo/Drivers directory to hold code that is common to multiple
2596 demo application projects.
2597 + Included some minor bug fixes in the uIP 1.0 code.
2598 + Added an lwIP demo for the STR9 - thanks ST for assistance.
2599 + Updated the AVR32 port to ensure correct behaviour with full compiler
2601 + Included binaries for OpenOCD FTDI and parallel port interfaces.
2603 Changes between V4.4.0 and V4.3.1 released July 31, 2007
2605 + Added AVR32 UC3B demo application.
2606 + Updated AVR32 UC3A port and demo applications.
2607 + Added IAR lwIP demo for AVR32 UC3A.
2608 + Updated listGET_OWNER_OF_NEXT_ENTRY() to assist compiler optimisation
2609 (thanks Niu Yong for making the suggestion).
2610 + Added xTaskGetSchedulerState() API function.
2611 + BUG FIX: Corrected behaviour when tasks that are blocked indefinitely
2612 have their block time adjusted (within xQueueSend() and xQueueReceive()),
2613 and are the subject of a call the vTaskResume() when they are not
2614 actually in the Suspended state (thanks Dan Searles for reporting the
2618 Changes between V4.3.0 and V4.3.1 released June 11, 2007
2620 + Added STMicroelectronics STM32 Cortex-M3 demo application.
2621 + Updated ustdlib.c for the GCC LM3S6965 demo.
2623 Changes between V4.2.1 and V4.3.0 released June 5, 2007
2625 + Introduced configKERNEL_INTERRUPT_PRIORITY to the IAR Cortex-M3, PIC24
2626 and dsPIC ports. See the LM3S6965 and PIC24 demo application
2627 documentation pages for more information.
2628 + Updated the PIC24 and dsPIC demos to build with V3.0 of the PIC30 GCC
2629 tools, and changed the demo applications.
2630 + Added demos for the new Ethernet and CAN enabled Luminary Micro Stellaris
2632 + Corrected bug in uIP the demos that prevented frames of approximately 1480
2633 bytes and over from being transmitted.
2634 + Included the LPC2368/uIP/Rowley demo into the main FreeRTOS.org
2636 + Update to WizC PIC18 port to permit its use with version 14 of the
2637 compiler. Thanks Marcel!
2639 Changes between V4.2.1 and V4.2.0 released April 2, 2007
2641 + Added AVR32 AT32UC3A ports for GCC and IAR.
2642 + Added -fomit-frame-pointer option to lwIP SAM7X demo makefile.
2643 + Moved location of call to LCD_Init() in STR9 demo to ensure it is only
2644 called after the scheduler has been started.
2646 Changes between V4.1.3 and V4.2.0 released February 8, 2007
2648 + Changes to both task.c and queue.c as a result of testing performed on
2649 the SafeRTOS code base.
2650 + Added Cortex-M3 LM3S811 demos for GCC and IAR tools.
2652 Changes between V4.1.2 and V4.1.3 released November 19, 2006
2654 + Added STR750 ARM7 port using the Raisonance RIDE/GCC tools.
2655 + Added -fomit-frame-pointer option to Rowley ARM7 demos as work around
2656 to GCC bug at some optimisation levels.
2657 + Altered the way the heap is defined in the LM3S811 Keil demo to prevent
2658 the RAM usage from counting toward the code size limit calculation.
2659 + CO-ROUTINE BUG FIX: Removed the call to prvIsQueueEmpty from within
2660 xQueueCRReceive as it exited with interrupts enabled. Thanks Paul Katz.
2661 + Tasks that block on events with a timeout of portMAX_DELAY are now
2662 blocked indefinitely if configINCLUDE_vTaskSuspend is defined.
2663 Previously portMAX_DELAY was just the longest block time possible. This
2664 is still the case if configINCLUDE_vTaskSuspend is not defined.
2665 + Minor changes to some demo application files.
2667 Changes between V4.1.1 and V4.1.2 released October 21, 2006
2669 + Added 16bit PIC ports and demos.
2670 + Added STR750 port and demo.
2673 Changes between V4.1.0 and V4.1.1 released September 24, 2006
2675 + Added the Luminary Micro Stellaris LM3S811 demo application.
2677 Changes between V4.0.5 and V4.1.0 released August 28, 2006
2679 + Prior to V4.1.0, under certain documented circumstances, it was possible
2680 for xQueueSend() and xQueueReceive() to return without having completed
2681 and without their block time expiring. The block time effectively
2682 stated a maximum block time, and the return value of the function needed
2683 to be checked to determine the reason for returning. This is no longer
2684 the case as the functions will only return once the block time has
2685 expired or they are able to complete their operation. It is therefore no
2686 longer necessary to wrap calls within loops.
2687 + Changed the critical section handling in the IAR AVR port to correct the
2688 behaviour when used with later compiler versions.
2689 + Added the LPC2138 CrossWorks demo into the zip file. Previously this was
2690 only available as a separate download.
2691 + Modified the AVR demo applications to demonstrate the use of co-routines.
2693 Changes between V4.0.4 and V4.0.5 released August 13, 2006
2695 + Introduced API function xTaskResumeFromISR(). Same functionality as
2696 xTaskResume(), but can be called from within an interrupt service routine.
2697 + Optimised vListInsert() in the case when the wake time is the maximum
2699 + Bug fix: The 'value' of the event list item is updated when the priority
2700 of a task is changed. Previously only the priority of the TCB itself was
2702 + vTaskPrioritySet() and vTaskResume() no longer use the event list item.
2703 This has not been necessary since V4.0.1 when the xMissedYield handling
2705 + Lowered the PCLK setting on the ARM9 STR9 demo from 96MHz to 48MHz.
2706 + When ending the scheduler - do not try to attempt a context switch when
2707 deleting the current task.
2708 + SAM7X EMAC drivers: Corrected the Rx frame length mask when obtaining
2709 the length from the rx descriptor.
2712 Changes between V4.0.3 and V4.0.4 released June 22, 2006
2714 + Added a port and demo application for the STR9 ARM9 based processors from
2716 + Slight optimisation to the vTaskPrioritySet() function.
2717 + Included the latest uIP version (1.0) in the demo/common/ethernet
2720 Changes between V4.0.2 and V4.0.3 released June 7, 2006
2722 + Added a port and demo application for the Cortex-M3 target using the IAR
2724 + The ARM Cortex-m3 Rowley projects have been updated to use V1.6 of the
2726 + The heap size defined for the lwIP Rowley demo has been reduced so that
2727 the project will link correctly when using the command line GCC tools
2728 also. The makefile has also been modified to allow debugging.
2729 + The lwIP Rowley demo not includes a 'kernel aware' debug window.
2730 + The uIP Rowley project has been updated to build with V1.6 of CrossWorks.
2731 + The second set of tasks in the blockQ demo were created the wrong way
2732 around (inconsistent to the description in the file). This has been
2735 Changes between V4.0.1 and V4.0.2 released May 28, 2006
2737 + Port and demo application added for the Tern Ethernet Engine controller.
2738 + Port and demo application added for MC9S12 using GCC, thanks to
2739 Jefferson "imajeff" Smith.
2740 + The function vTaskList() now suspends the scheduler rather than disabling
2741 interrupts during the creation of the task list.
2742 + Allow a task to delete itself by passing in its own handle. Previously
2743 this could only be done by passing in NULL.
2744 + Corrected the value passed to the WDG_PeriodValueConfig() library
2745 function in the STR71x demo.
2746 + The tick hook function is now called only within a tick isr. Previously
2747 it was also called when the tick function was called during the scheduler
2749 + The EMAC driver in the SAM7X lwIP demo has been made more robust as per
2750 the thread: https://sourceforge.net/forum/message.php?msg_id=3714405
2751 + In the PC ports: Add function prvSetTickFrequencyDefault() to set the
2752 DOS tick back to its proper value when the scheduler exits. Thanks
2754 + In the Borland x86 ports there was a mistake in the portFIRST_CONTEXT
2755 macro where the BP register was not popped from the stack correctly. The
2756 BP value would never get used so this did not cause a problem, but it has
2757 been corrected all the same.
2760 Changes between V4.0.0 and V4.0.1 released April 7 2006
2762 + Improved the ARM CORTEX M3 ports so they now only have to service
2764 + Added a Luminary Micro port and demo for use with Rowley CrossWorks.
2765 + Added the xMissedYield handling to tasks.c.
2767 Changes between V3.2.4 and V4.0.0
2771 + Added new RTOS port for Luminary Micros ARM CORTEX M3 microcontrollers.
2772 + Added new co-routine functionality.
2774 Other kernel changes:
2776 + An optional tick hook call is now included in the tick function.
2777 + Introduced the xMiniListItem structure and removed the list pxHead
2778 member in order to reduce RAM usage.
2779 + Added the following definitions to the FreeRTOSConfig.h file included
2782 configUSE_CO_ROUTINES
2783 configMAX_CO_ROUTINE_PRIORITIES
2784 + The volatile qualification has been changed on the list members to allow
2785 the task.c code to be tidied up a bit.
2786 + The scheduler can now be started even if no tasks have been created!
2787 This is to allow co-routines to run when there are no tasks.
2788 + A task being woken by an event will now preempt the currently running task
2789 even if its priority is only equal to the currently running task.
2791 Port and demo application changes:
2793 + Updated the WinAVR demo to compile with the latest version of WinAVR
2794 with no warnings generated.
2795 + Changed the WinAVR makefile to make chars signed - needed for the
2796 co-routine code if BaseType_t is set to char.
2797 + Added new demo application file crflash.c. This demonstrates co-routine
2798 functionality including passing data between co-routines.
2799 + Added new demo application file crhook.c. This demonstrates co-routine
2800 and tick hook functionality including passing data between and ISR and
2802 + Some NOP's were missing following stmdb{}^ instructions in various ARM7
2803 ports. These have been added.
2804 + Updated the Open Watcom PC demo project to include the crflash and crhook
2805 demo co-routines as an example of their use.
2806 + Updated the H8S demo to compile with the latest version of GCC.
2807 + Updated the SAM7X EMAC drivers to take into account the hardware errata
2808 regarding lost packets.
2809 + Changed the default MAC address used by some WEB server demos as the
2810 original addresses used was not liked by some routers.
2811 + Modified the SAM7X/IAR startup code slightly to prevent it hanging on
2812 some systems when the code is executed using a j-link debugger. The
2813 j-link macro file configures the PLL before the code executes so
2814 attempting to configure it again in the startup code was causing a
2815 problem for some user. Now a check is performed first to see if the
2816 PLL is already set up.
2817 + GCC port now contain all assembler code in a single asm block rather than
2818 individual blocks as before.
2819 + GCC LPC2000 code now explicitly uses R0 rather than letting the assembler
2820 choose the register to use as a temporary register during the context
2822 + Added portNOP() macro.
2823 + The compare match load value on LPC2000 ports now has 1 added to correct
2825 + The minimal stack depth has been increased slightly on the WIZC PIC18
2828 Changes between V3.2.3 and V3.2.4
2830 + Modified the GCC ARM7 port layer to allow use with GCC V4.0.0 and above.
2831 Many thanks to Glen Biagioni for the provided update.
2832 + Added a new Microblaze port and demo application.
2833 + Modified the SAM7X EMAC demo to default to use the MII interface rather
2834 than the RMII interface.
2835 + Modified the startup sequence of the SAM7X demo slightly to allow the
2836 EMAC longer to auto negotiate.
2838 Changes between V3.2.2 and V3.2.3
2840 + Added MII interface support to the SAM7X EMAC peripheral driver.
2841 Previously versions worked with the RMII interface only.
2842 + Added command line GCC support to the SAM7X lwIP demo. Previously the
2843 project could only be built using the CrossWorks IDE. Modifications to
2844 this end include the addition of a standard makefile and linker script to
2845 the download, and some adjustments to the stacks allocated to each task.
2846 + Changed the page returned by the lwIP WEB server demo to display the
2847 task status table rather than the TCP/IP statistics.
2848 + Corrected the capitalisation of some header file includes and makefile
2849 dependencies to facilitate use on Linux host computers.
2850 + The various LPC2000 ports had a mistake in the timer setup where the
2851 prescale value was written to T0_PC instead of T0_PR. This would have
2852 no effect unless a prescale value was actually required. This has been
2855 Changes between V3.2.1 and V3.2.2 - Released 23 September, 2005
2857 + Added an IAR port for the Philips LPC2129
2858 + The Atmel ARM7 IAR demo project files are now saved in the IAR Embedded
2859 Workbench V4.30a format.
2860 + Updated the J-Link macro file included with the SAM7X uIP demo project
2861 to allow the demo board to be reset over the J-Link.
2863 Changes between V3.2.0 and V3.2.1 - Released 1 September, 2005
2865 + Added lwIP demo for AT91SAM7X using Rowley tools.
2866 + Added uIP demo for AT91SAM7X using IAR tools.
2867 + Added function xTaskGetCurrentTaskHandle().
2868 + Renamed events.h to mevents.h to prevent it conflicting with the events.h
2869 generated automatically by the HCS12 processor expert utility. events.h
2870 is only used by the PC demo application.
2871 + Both PIC18 ports now initialise the TBLPTRU to 0 as this is the value
2872 expected by the compiler, and the compilers do not write to this
2874 + The HCS12 banked model demo now creates the 'suicide' tasks immediately
2875 prior to starting the scheduler. These tasks should be the last tasks to
2876 get started in order for the test to function correctly.
2878 Changes between V3.1.1 and V3.2.0 - Released 29 June, 2005
2880 V3.2.0 introduces two new MSP430 ports and corrects a minor kernel
2881 issues. Thanks to Ares.qi for his input.
2883 + Added two MSP430 ports that use the Rowley CrossWorks development tools.
2884 One port just mirrors the existing GCC port. The other port was provided
2885 by Milos Prokic. Thanks!
2886 + V3.2.0 corrects the behavior when vTaskPrioritySet() or vTaskResume()
2887 are called while the scheduler is locked (by a call to
2888 vTaskSuspendAll()). When this is done the subject task now starts to
2889 execute immediately when the scheduler is unlocked if it has the highest
2890 priority that is ready to run. Previously there was a possibility that
2891 the task would not run until the next RTOS tick or call to portYIELD().
2892 + Another similar small correction ensures that in the case where more than
2893 one task is blocked on a semaphore or queue, the task with the highest
2894 priority is guaranteed to be unblocked first.
2895 + Added a couple of more test tasks to the PC demo which cover the points
2898 Changes between V3.1.0 and V3.1.1 - Released 21st June, 2005
2900 This release updates the HCS12 port. The common kernel code
2903 + Updated the HCS12 port to support banking and introduced a demo
2904 application for the MC9S12DP256. The new demo application is
2905 located in the Demo/HCS12_CodeWarrior_banked directory.
2906 + The name of the directory containing the MC9S12F32 demo application
2907 has been changed to Demo/HCS12_CodeWarrior_small (as in 'small'
2909 + MC9S12F32 demo updated slightly to use the PLL. The CPU speed for the
2910 demo application is now 24MHz. Previously it was 8MHz.
2911 + The demo application file Demo/Common/Minimal/death.c has a slight
2912 alteration to prevent it using floating point variables.
2915 Changes between V3.0.0 and V3.1.0 - Released 11th June, 2005
2917 + Added new ports for ST Microsystems STR71x, and Freescale HCS12
2918 microcontrollers. Currently the HCS12 port is limited to the small
2919 memory model. Large memory models will be supported in the next
2921 + PIC18 wizC port updated. Thanks to Marcel van Lieshout for his
2922 continuing contribution.
2923 + The accuracy of the AVR port timer setup has been improved. Thanks to
2924 Thomas Krutmann for this contribution.
2925 + Added a new conditional compilation macro configIDLE_SHOULD_YIELD.
2926 See the WEB documentation for details.
2927 + Updated the CrossWorks uIP demo to build with V1.4 of CrossWorks.
2928 + Slight modification to the SAM7 release build configuration to correct
2929 an include path definition.
2930 + Updated the MPLAB PIC18 documentation to provide extra details on linker
2933 Changes between V3.0.0 and V2.6.1 - Released 23rd April, 2005
2935 V3.0.0 includes many enhancements, so this history list is broken into
2936 subsections as follows:
2940 Directory name changes
2941 Kernel and miscellaneous changes changes
2945 + Each port now defines BaseType_t as the data type that is most
2946 efficient for that architecture. The type BaseType_t is used
2947 extensively in API calls necessitating the following changes to the
2948 FreeRTOS API function prototypes.
2950 See the "New for V3.0.0" section of the FreeRTOS online
2951 documentation for full details of API changes.
2955 + The AT91FR40008 ARM7 port contributed by John Feller is now included
2956 in the download (thanks John!).
2957 + The PIC18 port for the wizC/fedC compiler contributed by Marcel van
2958 Lieshout is now included in the download (thanks Marcel!).
2959 + The IAR port for the AVR microcontroller has been upgraded to V3.0.0
2960 and is now a supported port.
2962 - Directory name changes
2964 For consistency, and to allow integration of the new ports, the
2965 following directory names have been changed.
2967 + The source/portable/GCC/ARM7 directory has been renamed
2968 source/portable/GCC/ARM7_LPC2000 so it is compatible with the naming
2969 of other GCC ARM7 ports.
2970 + The Demo/PIC directory has been renamed Demo/PIC18_MPLAB to
2971 accommodate the wizC/fedC PIC port.
2972 + The demo applications for the two AVR ports no longer share the same
2973 directory. The WinAVR demo is in the Demo/AVR_ATMega323_WinAVR
2974 directory and the IAR port in the Demo/AVR_ATMega323_IAR directory.
2977 - Kernel and miscellaneous changes changes
2979 See the "New for V3.0.0" section of the FreeRTOS online
2980 documentation for more information.
2982 + Previously 'portmacro.h' contained some user editable definitions
2983 relating to the user application, and some fixed definitions relating
2984 specifically to the port being used. The application specific
2985 definitions have been removed from 'portmacro.h' and placed inside a
2986 new header file called 'FreeRTOSConfig.h'. 'portmacro.h' should now
2987 never be modified by the user. A 'FreeRTOSConfig.h' is now included
2988 in each of FreeRTOS/Demo subdirectories - as it's settings relate to
2989 the demo application rather than being specific to the port.
2990 + Introduced configUSE_IDLE_HOOK in idle task.
2991 + The idle task will yield when another idle priority task is ready to
2992 run. Previously the idle task would run to the end of its time slice
2994 + The idle task is now created when the scheduler is started. This
2995 requires less stack than the previous scheme where it was created upon
2996 creation of the first application task.
2997 + The function usPortCheckFreeStackSpace() has been renamed
2998 usTaskCheckFreeStackSpace() and moved from the portable layer to
3000 + Corrected spelling of portMINMAL_STACK_SIZE to portMINIMAL_STACK_SIZE.
3001 + The portheap.c file included with the AVR port has been deleted. The
3002 AVR demo now uses the standard heap1 sample memory allocator.
3003 + The GCC AVR port is now build using the standard make utility. The
3004 batch files used previously have been deleted. This means a recent
3005 version of WinAVR is required in order to create a binary suitable for
3006 source level debugging.
3007 + vTaskStartScheduler() no longer takes the configUSE_PREEMPTION
3008 constant as a parameter. Instead the constant is used directly within
3009 tasks.c and no parameter is required.
3010 + The header file 'FreeRTOS.h' has been created and is used to include
3011 'projdefs.h', 'FreeRTOSConfig.h' and 'portable.h' in the necessary
3012 order. FreeRTOS.h can now be included in place of these other
3014 + The header file 'errors.h' has been deleted. The definitions it
3015 contained are now located within 'projdefs.h'.
3016 + pvPortMalloc() now takes a size_t parameter as per the ANSI malloc().
3017 Previously an unsigned short was used.
3018 + When resuming the scheduler a yield is performed if either a tick has
3019 been missed, or a task is moved from the pending ready list into a
3020 ready list. Previously a yield was not performed on this second
3022 + In heap1.c an overflow check has been added to ensure the next free
3023 byte variable does not wrap around.
3024 + Introduced the portTASK_FUNCTION() and portTASK_FUNCTION_PROTO()
3026 + The MPLAB PIC port now saved the TABLAT register in interrupt service
3029 Changes between V2.6.0 and V2.6.1 - Released Feb 22, 2005
3031 This version adds support for the H8 processor.
3035 + tskMAX_TASK_NAME_LEN removed from the task.h header and added to each
3036 individual portmacro.h file as portMAX_TASK_NAME_LEN. This allows RAM
3037 limited ports to allocate fewer characters to the task name.
3038 + AVR port - Replaced the inb() and outb() functions with direct memory
3039 access. This allows the port to be built with the 20050414 build of
3041 + GCC LPC2106 port - removed the 'static' from the definition of
3042 vNonPreemptiveTick() to allow the demo to link when using the cooperative
3044 + GCC LPC2106 port - Corrected the optimisation options in the batch files
3045 ROM_THUMB.bat, RAM_THUMB.bat, ROM_ARM.bat and RAM_ARM.bat. The lower case
3046 -o is replaced by an uppercase -O.
3047 + Tasks.c - The strcpy call has been removed when copying across the task
3049 + Updated the trace visualisation to always be 4 byte aligned so it can be
3050 used on ARM architectures.
3051 + There are now two tracecon executables (that convert the trace file binary
3052 into an ASCII file). One for big endian targets and one for little endian
3054 + Added ucTasksDeleted variable to prevent vTaskSuspendAll() being called
3055 too often in the idle task.
3056 + SAM7 USB driver - Replaced the duplicated RX_DATA_BK0 in the interrupt
3057 mask with the RX_DATA_BK1.
3060 Changes between V2.5.5 and V2.6.0 - Released January 16, 2005
3062 + Added the API function vTaskDelayUntil(). The demo app file
3063 Demo/Common/Minimal/flash.c has been updated to demonstrate its use.
3064 + Added INCLUDE_vTaskDelay conditional compilation.
3065 + Changed the name of the Demo/ARM7_AtmelSAM7S64_IAR directory to
3066 Demo/ARM7_AT91SAM7S64_IAR for consistency.
3067 + Modified the AT91SAM7S USB driver to allow descriptors that have
3068 a length that is an exact multiple of the FIFO to be transmitted.
3070 Changes between V2.5.4 and V2.5.5 - Released January 3, 2005
3072 This version adds support for the Atmel SAM7 ARM7 microcontrollers
3073 along with the IAR development tools.
3077 + Renamed the Demo/ARM7 directory to Demo/ARM7_LPC2106_GCC.
3078 + Renamed the Demo/ARM7_Keil directory to Demo/ARM7_LPC2129_Keil.
3079 + Modified the Philips ARM7 serial interrupt service routines to only
3080 process one interrupt per call. This seems to enable the ISR to
3081 operate more quickly.
3082 + Removed the 'far' keyword from the Open Watcom portable layer source
3083 files. This allows their use with V1.3 of Open Watcom.
3084 + Minor modifications to the SDCC build files to allow their use under
3085 Linux. Thanks to Frieder Ferlemann for this contribution.
3086 + Small change to sTaskCreate() to allow a context switch even when
3087 pxCreatedTask is NULL. Thanks to Kamil for this contribution.
3088 + inline keyword removed from vTaskSwitchContext() and VTaskIncrementTick()
3091 Changes between V2.5.3 and V2.5.4 - Released Dec 1, 2004
3093 This is an important maintenance release.
3095 The function cTaskResumeAll() has been modified so it can be used safely
3096 prior to the kernel being initialised. This was an issue as
3097 cTaskResumeAll() is called from pvPortMalloc(). Thanks to Daniel Braun
3098 for highlighting this issue.
3100 Changes between V2.5.2 and V2.5.3 - Released Nov 2, 2004
3102 The critical section handling functions have been changed for the GCC ARM7
3103 port. Some optimisation levels use the stack differently to others. This
3104 means the interrupt flags cannot always be stored on the stack and are
3105 instead now stored in a variable, which is then saved as part of the
3106 tasks context. This allows the GCC ARM7 port to be used at all
3107 optimisation levels - including -Os.
3109 Other minor changes:
3111 + MSP430 definition of usCriticalNesting now uses the volatile qualifier.
3112 This is probably not required but added just in case.
3114 Changes between V2.5.1 and V2.5.2 - Released Oct 26, 2004
3116 + Added the Keil ARM7 port.
3117 + Slight modification to comtest.c to make the delay periods more random.
3118 This creates a better test condition.
3120 Changes between V2.5.0 and V2.5.1 - Released Oct 9, 2004
3122 + Added the MSP430 port.
3123 + Extra comments added to the GCC ARM7 port.c and portISR.c files.
3124 + The memory pool allocated within heap_1.c has been placed within a
3125 structure to ensure correct memory alignment on 32bit systems.
3126 + Within the GCC ARM7 serial drivers an extra check is made to ensure
3127 the post to the queue was successful if then attempting immediately
3128 retrieve the posted character.
3129 + Changed the name of the constant portTICKS_PER_MS to portTICK_PERIOD_MS
3130 as the old name was misleading.
3133 Changes between V2.4.2 and V2.5.0 - Released Aug 12, 2004
3135 The RTOS source code download now includes three separate memory allocation
3136 schemes - so you can choose the most appropriate for your application.
3137 These are found in the Source/Portable/MemMang directory. The demo
3138 application projects have also been updated to demonstrate the new schemes.
3139 See the "Memory Management" page of the API documentation for more details.
3141 + Added heap_1.c, heap_2.c and heap_3.c in the Source/Portable/MemMang
3143 + Replaced the portheap.c files for each demo application with one of the
3144 new memory allocation files.
3145 + Updated the portmacro.h file for each demo application to include the
3146 constants required for the new memory allocators: portTOTAL_HEAP_SIZE and
3148 + Added a new test to the ARM7 demo application that tests the operation
3149 of the heap_2 memory allocator.
3152 Changes between V2.4.1 and V2.4.2 - Released July 14, 2004
3154 + The ARM7 port now supports THUMB mode.
3155 + Modification to the ARM7 demo application serial port driver.
3157 Changes between V2.4.0 and V2.4.1 - Released July 2, 2004
3159 + Rationalised the ARM7 port version of portEXIT_CRITICAL() -
3160 improvements provided by Bill Knight.
3161 + Made demo serial driver more complete and robust.
3164 Changes between V2.4.0 and V2.3.1 - Released June 30, 2004
3166 + Added the first ARM7 port - thanks to Bill Knight for the assistance
3168 + Added extra files to the Demo/Common/Minimal directory. These are
3169 equivalent to their Demo/Common/Full counterparts but with the
3170 calls to the functions defined in print.c removed.
3171 + Added TABLAT to the list of registers saved as part of a PIC18 context.
3173 Changes between V2.3.0 and V2.3.1 - Released June 25, 2004
3175 + Changed the way the vector table is defined to be more portable.
3176 + Corrected the definitions of SPH and SPL in portmacro.s90.
3177 The previous definitions prevented V2.3.0 operating if the iom323.h
3178 header file was included in portmacro.s90.
3180 Changes between V2.2.0 and V2.3.0 - Released June 19, 2004
3182 + Added an AVR port that uses the IAR compiler.
3183 + Explicit use of 'signed' qualifier on plain char types.
3184 + Modified the Open Watcom project files to use 'signed' as the
3186 + Changed odd calculation of initial pxTopOfStack value when
3187 portSTACK_GROWTH < 0.
3188 + Added inline qualifier to context switch functions within task.c.
3189 Ports that do not support the (non ANSI) inline keyword have the
3190 inline #define'd away in their respective portmacro.h files.
3192 Changes between V2.1.1 and V2.2.0 - Released May 18, 2004
3194 + Added Cygnal 8051 port.
3195 + PCLATU and PCLATH are now saved as part of the PIC18 context. This
3196 allows function pointers to be used within tasks. Thanks to Javier
3197 Espeche for the enhancement.
3198 + Minor changes to demo application files to reduce stack usage.
3199 + Minor changes to prevent compiler warnings when compiling the new port.
3201 Changes between V2.1.0 and V2.1.1 - Released March 12, 2004
3203 + Bug fix - pxCurrentTCB is now initialised before the call to
3204 prvInitialiseTaskLists(). Previously pxCurrentTCB could be accessed
3205 while null during the initialisation sequence. Thanks to Giuseppe
3206 Franco for the correction.
3208 Changes between V2.0.0 and V2.1.0 - Released Feb 29, 2004
3210 V2.1.0 has significant reworks that greatly reduce the amount of time
3211 the kernel has interrupts disabled. The first section of modifications
3212 listed here must be taken into account by users. The second section
3213 are related to the kernel implementation and as such are transparent.
3217 + The typedef TickType_t has been introduced. All delay times should
3218 now use a variable of type TickType_t in place of the unsigned long's
3219 used previously. API function prototypes have been updated
3221 + The configuration macro USE_16_BIT_TICKS has been introduced. If set
3222 to 1 TickType_t is defined as an unsigned short. If set to 0
3223 TickType_t is defined as an unsigned long. See the configuration
3224 section of the API documentation for more details.
3225 + The configuration macro INCLUDE_vTaskSuspendAll is now obsolete.
3226 + vTaskResumeAll() has been renamed cTaskResumeAll() as it now returns a
3227 value (see the API documentation).
3228 + ulTaskGetTickCount() has been renamed xTaskGetTickCount() as the type
3229 it returns now depends on the USE_16_BIT_TICKS definition.
3230 + cQueueReceive() must now >never< be used from within an ISR. Use the new
3231 cQueueReceiveFromISR() function instead.
3235 + A mechanism has been introduced that allows a queue to be accessed by
3236 a task and ISR simultaneously.
3237 + A "pending ready" queue has been introduced that enables interrupts to
3238 be processed when the scheduler is suspended.
3239 + The list implementation has been improved to provide faster item
3241 + The scheduler now makes use of the scheduler suspend mechanism in places
3242 where previously interrupts were disabled.
3244 Changes between V1.2.6 and V2.0.0 - Released Jan 31, 2004
3246 + Introduced new API functions:
3253 + Added conditional compilation options that allow the components of the
3254 kernel that are unused by an application to be excluded from the build.
3255 See the Configuration section on the WEB site for more information (on
3256 the API pages). The macros have been added to each portmacro.h file (
3257 sometimes called prtmacro.h).
3258 + Rearranged tasks.c.
3259 + Added demo application file dynamic.c.
3260 + Updated the PC demo application to make use of dynamic.c.
3261 + Updated the documentation contained in the kernel header files.
3262 + Creating a task now causes a context switch if the task being created
3263 has a higher priority than the calling task - assuming the kernel is
3265 + vTaskDelete() now only causes a context switch if the calling task is
3266 the task being deleted.
3268 Changes between V1.2.5 and V1.2.6 - Released December 31, 2003
3270 Barring the change to the interrupt vector (PIC port) these are minor
3273 + The interrupt vector used for the PIC master ISR has been changed from
3274 0x18 to 0x08 - where it should have always been. The incorrect address
3275 still works but probably executes a number of NOP's before getting to the
3277 + Changed the baud rate used by the AVR demo application to 38400. This
3278 has an error percentage of less than one percent with an 8MHz clock.
3279 + Raised the priority of the Rx task in demo\full\comtest.c. This only
3280 affects the Flashlite and PC ports. This was done to prevent the Rx
3281 buffer becoming full.
3282 + Reverted the Flashlite COM port driver back so it does not use the DMA.
3283 The DMA appears to miss characters under stress. The Borland Flashlite
3284 port was also calculating a register value incorrectly resulting in the
3285 wrong DMA source address being used. The same code worked fine when
3286 compiling with Open Watcom. Other minor enhancements were made to the
3288 + Modified the PIC serial Rx ISR to check for and clear overrun errors.
3289 Overrun errors seem to prevent any further characters being received.
3290 + The PIC demo projects now have some optimisation switched on.
3293 Changes between V1.2.4 and V1.2.5
3295 Small fix made to the PIC specific port.c file described below.
3297 + Introduced portGLOBAL_INTERRUPT_FLAG definition to test the global
3298 interrupt flag setting. Using the two bits defined within
3299 portINITAL_INTERRUPT_STATE was causing the w register to get clobbered
3300 before the test was performed.
3302 Changes between V1.2.3 and V1.2.4
3304 V1.2.4 contains a release version of the PIC18 port.
3305 An optional exception has been included with the GPL. See the licensing
3306 section of www.FreeRTOS.org for details.
3308 + The function xPortInitMinimal() has been renamed to
3309 xSerialPortInitMinimal() and the function xPortInit() has been renamed
3310 to xSerialPortInit().
3311 + The function sSerialPutChar() has been renamed cSerialPutChar() and
3312 the function return type changed to portCHAR.
3313 + The integer and flop tasks now include calls to tskYIELD(), allowing
3314 them to be used with the cooperative scheduler.
3315 + All the demo applications now use the integer and comtest tasks when the
3316 cooperative scheduler is being used. Previously they were only used with
3317 the preemptive scheduler.
3318 + Minor changes made to operation of minimal versions of comtest.c and
3320 + The ATMega port definition of portCPU_CLOSK_HZ definition changed to
3321 8MHz base 10, previously it base 16.
3325 Changes between V1.2.2a and V1.2.3
3327 The only change of any significance is to the license, which has changed
3328 from the Open Software License to the GNU GPL.
3330 The zip file also contains a pre-release version of the PIC18 port. This
3331 has not yet completed testing and as such does not constitute part of the
3332 V1.2.3 release. It is still however covered by the GNU GPL.
3334 There are minor source code changes to accommodate the PIC C compiler.
3335 These mainly involve more explicit casting.
3337 + sTaskCreate() has been modified slightly to make use of the
3338 portSTACK_GROWTH macro. This is required for the PIC port where the
3339 stack grows in the opposite direction to the other existing ports.
3340 + prvCheckTasksWaitingTermination() has been modified slightly to bring
3341 the decrementing of usCurrentNumberOfTasks within the critical section,
3342 where it should have been since the creation of an eight bit port.
3344 Changes between V1.2.2 and V1.2.2a
3346 The makefile and buildcoff.bat files included with the AVR demo application
3347 have been modified for use with the September 2003 build of WinAVR. No
3348 source files have changed.
3350 Changes between V1.2.1 and V1.2.2
3352 There are only minor changes here to allow the PC and Flashlite 186 ports
3353 to use the Borland V4.52 compiler, as supplied with the Flashlite 186
3356 + Introduced a BCC directory under source\portable. This contains all the
3357 files specific to the Borland compiler port.
3358 + Corrected the macro naming of portMS_PER_TICK to portTICKS_PER_MS.
3359 + Modified comtest.c to increase the rate at which the string is
3360 transmitted and received on the serial port. The Flashlite 186 demo
3361 app baud rate has also been increased.
3362 + The values of the constants used in both integer.c files have been
3363 increased to force the Borland compiler to use 32 bit values. The
3364 Borland optimiser placed the previous values in 16 bit registers, and in
3365 So doing invalidated the test.
3367 Changes between V1.2.0 and V1.2.1
3369 This version includes some minor changes to the list implementation aimed
3370 at improving the context switch time - with is now approximately 10% faster.
3371 Changes include the removal of some null pointer assignment checks. These
3372 were redundant where the scheduler uses the list functions, but means any
3373 user application choosing to use the same list functions must now check
3374 that no NULL pointers are passed as a parameter.
3376 The Flashlite 186 serial port driver has also been modified to use a DMA
3377 channel for transmissions. The serial driver is fully functional but still
3378 under development. Flashlite users may prefer to use V1.2.0 for now.
3382 + Changed the baud rate for the ATMega323 serial test from 19200 to 57600.
3383 + Use vSerialPutString() instead of single character puts in
3384 Demo\Full\Comtest.c. This allows the use of the flashlite DMA serial
3385 driver. Also the check variable only stops incrementing after two
3386 consecutive failures.
3387 + semtest.c creates four tasks, two of which operate at the idle priority.
3388 The tasks that operate at the idle priority now use a lower expected
3389 count than those running at a higher priority. This prevents the low
3390 priority tasks from signalling an error because they have not been
3391 scheduled enough time for each of them to count the shared variable to
3392 the higher original value.
3393 + The flashlite 186 serial driver now uses a DMA channel for transmissions.
3394 + Removed the volatile modifier from the list function parameters. This was
3395 only ever included to prevent compiler warnings. Now warnings are
3396 removed by casting parameters where the calls are made.
3397 + prvListGetOwnerOfNextEntry() and prvListGetOwnerOfHeadEntry() have been
3398 removed from list.c and added as macros in list.h.
3399 + usNumberOfItems has been added to the list structure. This removes the
3400 need for a pointer comparison when checking if a list is empty, and so
3402 + Removed the NULL check in vListRemove(). This makes the call faster but
3403 necessitates any application code utilising the list implementation to
3404 ensure NULL pointers are not passed.
3405 + Renamed portTICKS_PER_MS definition to portMS_PER_TICK (milli seconds
3406 per tick). This is what it always should have been.
3408 Changes between V1.01 and V1.2.0
3410 The majority of these changes were made to accommodate the 8bit AVR port.
3411 The scheduler workings have not changed, but some of the data types used
3412 have been made more friendly to an eight bit environment.
3416 + Changed the version numbering format.
3418 + Split the directory demo\common into demo\common\minimal and
3419 demo\common\full. The files in the full directory are for systems with
3420 a display (currently PC and Flashlite 186 demo's). The files in the
3421 minimal directory are for systems with limited RAM and no display
3422 (currently MegaAVR).
3423 + Minor changes to demo application function prototypes to make more use
3425 + Within the scheduler itself the following functions have slightly
3426 modified declarations to make use of 8bit data types where possible:
3430 usQueueMessageWaiting(),
3431 sQueueSendFromISR(),
3434 sSemaphoreGiveFromISR(),
3436 sTaskMoveFromEventList().
3438 Where the return type has changed the function name has also changed in
3439 accordance with the naming convention. For example
3440 usQueueMessageWaiting() has become ucQueueMessageWaiting().
3441 + The definition tskMAX_PRIORITIES has been moved from task.h to
3442 portmacro.h and renamed portMAX_PRIORITIES. This allows different
3443 ports to allocate a different maximum number of priorities.
3444 + By default the trace facility is off, previously USE_TRACE_FACILITY
3446 + comtest.c now uses a pseudo random delay between sends. This allows for
3447 better testing as the interrupts do not arrive at regular intervals.
3448 + Minor change to the Flashlite serial port driver. The driver is written
3449 to demonstrate the scheduler and is not written to be efficient.
3453 Changes between V1.00 and V1.01
3455 These changes improve the ports. The scheduler itself has not changed.
3457 Improved context switch mechanism used when performing a context
3458 switch from an ISR (both the tick ISR and the serial comms ISR's within
3459 the demo application). The new mechanism is faster and uses less stack.
3461 The assembler file portasm.asm has been replaced by a header file
3462 portasm.h. This includes a few assembler macro definitions.
3464 All saving and restoring of registers onto/off of the stack is now handled
3465 by the compiler. This means the initial stack setup for a task has to
3466 mimic the stack used by the compiler, which is different for debug and
3469 Slightly changed the operation of the demo application, details below.
3473 + portSWITCH_CONTEXT() replaced by vPortFirstContext().
3474 + pxPortInitialiseStack() modified to replicate the stack used by the
3476 + portasm.asm file removed.
3477 + portasm.h introduced. This contains macro definitions for
3478 portSWITCH_CONTEXT() and portFIRST_CONTEXT().
3479 + Context switch from ISR now uses the compiler generated interrupt
3480 mechanism. This is done simply by calling portSWITCH_CONTEXT and leaving
3481 the save/restore to compiler generated code.
3482 + Calls to taskYIELD() during ISR's have been replaced by calling the
3483 simpler and faster portSWITCH_CONTEXT().
3484 + The Flashlite 186 port now uses 186 instruction set (used to use 80x86
3486 + The blocking queue tasks within the demo application did not operate
3487 quite as described. This has been corrected.
3488 + The priority of the comtest Rx task within the demo application has been
3489 lowered. Received characters are now processed (read from the queue) at
3490 the idle priority, allowing low priority tasks to run evenly at times of
3491 a high communications overhead.
3492 + Prevent the call to kbhit() in main.c for debug builds as the debugger
3493 seems to have problems stepping over the call. This if for the PC port
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