1 Documentation and download available at https://www.FreeRTOS.org/
3 Changes between FreeRTOS V10.5.1 and FreeRTOS 10.6.0 released July 13, 2023
5 + Add a new MPU wrapper that places additional restrictions on unprivileged
6 tasks. The following is the list of changes introduced with the new MPU
9 1. Opaque and indirectly verifiable integers for kernel object handles:
10 All the kernel object handles (for example, queue handles) are now
11 opaque integers. Previously object handles were raw pointers.
12 2. Save the task context in Task Control Block (TCB): When a task is
13 swapped out by the scheduler, the task's context is now saved in its
14 TCB. Previously the task's context was saved on its stack.
15 3. Execute system calls on a separate privileged only stack: FreeRTOS
16 system calls, which execute with elevated privilege, now use a
17 separate privileged only stack. Previously system calls used the
18 calling task's stack. The application writer can control the size of
19 the system call stack using new configSYSTEM_CALL_STACK_SIZE config
21 4. Memory bounds checks: FreeRTOS system calls which accept a pointer
22 and de-reference it, now verify that the calling task has required
23 permissions to access the memory location referenced by the pointer.
24 5. System calls restrictions: The following system calls are no longer
25 available to unprivileged tasks:
28 - xQueueCreateMutexStatic
29 - xQueueCreateCountingSemaphore
30 - xQueueCreateCountingSemaphoreStatic
32 - xQueueGenericCreateStatic
43 - xTaskCallApplicationTaskHook
45 - vTaskGetRunTimeStats
48 - xEventGroupCreateStatic
50 - xStreamBufferGenericCreate
51 - xStreamBufferGenericCreateStatic
54 Also, an unprivileged task can no longer use vTaskSuspend to suspend
55 any task other than itself.
57 We thank the following people for their inputs in these enhancements:
58 - David Reiss of Meta Platforms, Inc.
59 - Lan Luo, Xinhui Shao, Yumeng Wei, Zixia Liu, Huaiyu Yan and Zhen Ling
60 of School of Computer Science and Engineering, Southeast University,
62 - Xinwen Fu of Department of Computer Science, University of
63 Massachusetts Lowell, USA.
64 - Yueqi Chen, Zicheng Wang, Minghao Lin, Jiahe Wang of University of
65 Colorado Boulder, USA.
66 + Add Cortex-M35P port. Contributed by @urutva.
67 + Add embedded extension (RV32E) support to the IAR RISC-V port.
68 + Add ulTaskGetRunTimeCounter and ulTaskGetRunTimePercent APIs. Contributed by
70 + Add APIs to get the application supplied buffers from statically
71 created kernel objects. The following new APIs are added:
72 - xTaskGetStaticBuffers
73 - xQueueGetStaticBuffers
74 - xQueueGenericGetStaticBuffers
75 - xSemaphoreGetStaticBuffer
76 - xEventGroupGetStaticBuffer
77 - xStreamBufferGetStaticBuffers
78 - xMessageBufferGetStaticBuffers
79 These APIs enable the application writer to obtain static buffers from
80 the kernel object and free/reuse them at the time of deletion. Earlier
81 the application writer had to maintain the association of static buffers
82 and the kernel object in the application. Contributed by @Dazza0.
83 + Add Thread Local Storage (TLS) support using picolibc function. Contributed
85 + Add configTICK_TYPE_WIDTH_IN_BITS to configure TickType_t data type. As a result,
86 the number of bits in an event group also increases with big data type. Contributed
88 + Update eTaskGetState and uxTaskGetSystemState to return eReady for pending ready
89 tasks. Contributed by @Dazza0.
90 + Update heap_4 and heap_5 to add padding only if the resulting block is not
92 + Fix the scheduler logic in a couple of places to not preempt a task when an
93 equal priority task becomes ready.
94 + Add macros used in FreeRTOS-Plus libraries. Contributed by @Holden.
95 + Fix clang compiler warnings. Contributed by @phelter.
96 + Add assertions to ARMv8-M ports to detect when FreeRTOS APIs are called from
97 interrupts with priority higher than the configMAX_SYSCALL_INTERRUPT_PRIORITY.
98 Contributed by @urutva.
99 + Add xPortIsInsideInterrupt API to ARM_CM0 ports.
100 + Fix build warning in MSP430X port when large data model is used.
101 + Add the ability to use Cortex-R5 port on the parts without FPU.
102 + Fix build warning in heap implementations on PIC24/dsPIC.
103 + Update interrupt priority asserts for Cortex-M ports so that these do not fire
104 on QEMU which does not implement PRIO bits.
105 + Update ARMv7-M ports to ensure that kernel interrupts run at the lowest priority.
106 configKERNEL_INTERRUPT_PRIORITY is now obsolete for ARMv7-M ports and brings
107 these ports inline with the newer ARMv8-M ports. Contributed by @chrisnc.
108 + Fix build issue in POSIX GCC port on Windows Subsystem for Linux (WSL). Contributed
110 + Add portMEMORY_BARRIER to Microblaze port. Contributed by @bbain.
111 + Add portPOINTER_SIZE_TYPE definition for ATmega port. Contributed by @jputcu.
112 + Multiple improvements in the CMake support. Contributed by @phelte and @cookpate.
114 Changes between FreeRTOS V10.5.0 and FreeRTOS V10.5.1 released November 16 2022
115 + Updated the kernel version in manifest and SBOM
117 Changes between FreeRTOS V10.4.6 and FreeRTOS V10.5.0 released September 16 2022
119 + ARMv7-M and ARMv8-M MPU ports: It was possible for a third party that
120 already independently gained the ability to execute injected code to
121 read from or write to arbitrary addresses by passing a negative argument
122 as the xIndex parameter to pvTaskGetThreadLocalStoragePointer() or
123 vTaskSetThreadLocalStoragePointer respectively. A check has been added to
124 ensure that passing a negative argument as the xIndex parameter does not
125 cause arbitrary read or write.
126 We thank Certibit Consulting, LLC for reporting this issue.
127 + ARMv7-M and ARMv8-M MPU ports: It was possible for an unprivileged task
128 to invoke any function with privilege by passing it as a parameter to
129 MPU_xTaskCreate, MPU_xTaskCreateStatic, MPU_xTimerCreate,
130 MPU_xTimerCreateStatic, or MPU_xTimerPendFunctionCall. MPU_xTaskCreate
131 and MPU_xTaskCreateStatic have been updated to only allow creation of
132 unprivileged tasks. MPU_xTimerCreate, MPU_xTimerCreateStatic and
133 MPU_xTimerPendFunctionCall APIs have been removed.
134 We thank Huazhong University of Science and Technology for reporting
136 + ARMv7-M and ARMv8-M MPU ports: It was possible for a third party that
137 already independently gained the ability to execute injected code to
138 achieve further privilege escalation by branching directly inside a
139 FreeRTOS MPU API wrapper function with a manually crafted stack frame.
140 The local stack variable `xRunningPrivileged` has been removed so that
141 a manually crafted stack frame cannot be used for privilege escalation
142 by branching directly inside a FreeRTOS MPU API wrapper.
143 We thank Certibit Consulting, LLC, Huazhong University of Science and
144 Technology and the SecLab team at Northeastern University for reporting
146 + ARMv7-M MPU ports: It was possible to configure overlapping memory
147 protection unit (MPU) regions such that an unprivileged task could access
148 privileged data. The kernel now uses highest numbered MPU regions for
149 kernel protections to prevent such MPU configurations.
150 We thank the SecLab team at Northeastern University for reporting this
152 + Add support for ARM Cortex-M55.
153 + Add support for ARM Cortex-M85. Contributed by @gbrtth.
154 + Add vectored mode interrupt support to the RISC-V port.
155 + Add support for RV32E extension (Embedded Profile) in RISC-V GCC port.
156 Contributed by @Limoto.
158 - Add a check to heap_2 to track if a memory block is allocated to
159 the application or not. The MSB of the size field is used for this
160 purpose. The same check already exists in heap_4 and heap_5. This
161 check prevents double free errors.
162 - Add a new flag configHEAP_CLEAR_MEMORY_ON_FREE to heap_2, heap_4
163 and heap_5. If the flag is set in FreeRTOSConfig.h then memory freed using
164 vPortFree() is automatically cleared to zero.
165 - Add a new API pvPortCalloc to heap_2, heap_4 and heap_5 which has the same
166 signature as the standard library calloc function.
167 - Update the pointer types to portPOINTER_SIZE_TYPE. Contributed by
169 + Add the ability to override send and receive completed callbacks for each
170 instance of a stream buffer or message buffer. Earlier there could be
171 one send and one receive callback for all instances of stream and message
172 buffers. Having separate callbacks per instance allows different message
173 and stream buffers to be used differently - for example, some for inter core
174 communication and others for same core communication.
175 The feature can be controlled by setting the configuration option
176 configUSE_SB_COMPLETED_CALLBACK in FreeRTOSConfig.h. When the option is set to 1,
177 APIs xStreamBufferCreateWithCallback() or xStreamBufferCreateStaticWithCallback()
178 (and likewise APIs for message buffer) can be used to create a stream buffer
179 or message buffer instance with application provided callback overrides. When
180 the option is set to 0, then the default callbacks as defined by
181 sbSEND_COMPLETED() and sbRECEIVE_COMPLETED() macros are invoked. To maintain
182 backwards compatibility, configUSE_SB_COMPLETED_CALLBACK defaults to 0. The
183 functionality is currently not supported for MPU enabled ports.
184 + Generalize the FreeRTOS's Thread Local Storage (TLS) support so that it
185 is not tied to newlib and can be used with other c-runtime libraries also.
186 The default behavior for newlib support is kept same for backward
188 + Add support to build and link FreeRTOS using CMake build system. Contributed
190 + Add support to generate Software Bill of Materials (SBOM) for every release.
191 + Add support for 16 MPU regions to the GCC Cortex-M33 ports.
192 + Add ARM Cortex-M7 r0p0/r0p1 Errata 837070 workaround to ARM CM4 MPU ports.
193 The application writer needs to define configENABLE_ERRATA_837070_WORKAROUND
194 when using CM4 MPU ports on a Cortex-M7 r0p0/r0p1 core.
195 + Add configSYSTICK_CLOCK_HZ to Cortex-M0 ports. This is needed to support
196 the case when the SysTick timer is not clocked from the same source as the CPU.
197 + Add hardware stack protection support to MicroBlazeV9 port. This ensures that
198 the CPU immediately raises Stack Protection Violation exception as soon as any
199 task violates its stack limits. Contributed by @uecasm.
200 + Introduce the configUSE_MINI_LIST_ITEM configuration option. When this
201 option is set to 1, ListItem_t and MiniLitItem_t remain separate types.
202 However, when configUSE_MINI_LIST_ITEM == 0, MiniLitItem_t and ListItem_t
203 are both typedefs of the same struct xLIST_ITEM. This addresses some issues
204 observed when strict-aliasing and link time optimization are enabled.
205 To maintain backwards compatibility, configUSE_MINI_LIST_ITEM defaults to 1.
206 + Simplify prvInitialiseNewTask to memset newly allocated TCB structures
207 to zero, and remove code that set individual structure members to zero.
208 + Add prototype for prvPortYieldFromISR to the POSIX port so that it builds
209 without any warning with -Wmissing-prototypes compiler option.
210 + Add top of stack and end of stack to the task info report obtained using
211 vTaskGetInfo(). Contributed by @shreyasbharath.
212 + Add a cap to the cRxLock and cTxLock members of the queue data structure.
213 These locks count the number items received and sent to the queue while
214 the queue was locked. These are later used to unblock tasks waiting on
215 the queue when the queue is unlocked. This PR caps the values of the
216 cRxLock and cTxLock to the number of tasks in the system because we cannot
217 unblock more tasks than there are in the system. Note that the same assert
218 could still be triggered is the application creates more than 127 tasks.
219 + Changed uxAutoReload parameter in timer functions to xAutoReload. The
220 type is now BaseType_t. This matches the type of pdTRUE and pdFALSE.
221 The new function xTimerGetAutoReload() provides the auto-reload state as
222 a BaseType_t. The legacy function uxTimerGetAutoReload is retained with the
223 original UBaseType_t return value.
224 + Fix support for user implementations of tickless idle that call
225 vTaskStepTick() with xExpectedIdleTime ticks to step. The new code
226 ensures xTickCount reaches xNextTaskUnblockTime inside xTaskIncrementTick()
227 instead of inside vTaskStepTick(). This fixes the typical case where a task
228 wakes up one tick late and a rare case assertion failure when xTickCount\
229 rolls over. Contributed by @jefftenney.
230 + Fix deadlock in event groups when pvPortMalloc and vPortFree functions
231 are protected with a mutex. Contributed by @clemenskresser.
232 + Fix a warning in tasks.c when compiled with -Wduplicated-branches
233 GCC option. Contributed by @pierrenoel-bouteville-act.
234 + Fix compilation error in tasks.c when configSUPPORT_DYNAMIC_ALLOCATION
235 is set to zero. Contributed by @rdpoor.
236 + Fix prvWriteMessageToBuffer() function in stream_buffer.c so that it correctly
237 copies length on big endian platforms too.
238 + Remove the need for INCLUDE_vTaskSuspend to be set to 1
239 when configUSE_TICKLESS_IDLE is enabled. Contributed by @pramithkv.
240 + Update the RL78 IAR port to the latest version of IAR which uses the
241 industry standard ELF format as opposed to earlier UBROF object format.
242 Contributed by @felipe-iar.
243 + Add tick type is atomic flag when tick count is 16-bit to PIC24 port. This
244 allows the PIC24 family of 16 bit processors to read the tick count without
245 a critical section when the tick count is also 16 bits.
246 + Fix offset-out-of-range errors for GCC CM3/CM4 mpu ports when
247 Link Time Optimization is enabled. Contributed by @niniemann.
248 + Remove #error when RISC-V port is compiled on a 64-bit RISC-V platform.
249 Contributed by @cmdrf.
250 + Fix ullPortInterruptNesting alignment in Cortex-A53 port so that it is
251 8-byte aligned. This fixes the unaligned access exception. Contributed
253 + Fix Interrupt Handler Register Function and Exception Process in NiosII
254 Port. Contributed by @ghost.
255 + Change FreeRTOS IRQ Handler for Cortex-A53 SRE port to store and restore
256 interrupt acknowledge register. This ensures that the SRE port behavior
257 matches the Memory Mapped IO port. Contributed by @sviaunxp.
258 + Update the uncrustify config file to match the version of the uncrustify
259 used in the CI Action. Also, pin the version of uncrustify in CI. Contributed
262 Changes between FreeRTOS V10.4.5 and FreeRTOS V10.4.6 released November 12 2021
264 + ARMv7-M and ARMv8-M MPU ports – prevent non-kernel code from calling the
265 internal functions xPortRaisePrivilege and vPortResetPrivilege by changing
267 + Introduce a new config configALLOW_UNPRIVILEGED_CRITICAL_SECTIONS which
268 enables developers to prevent critical sections from unprivileged tasks.
269 It defaults to 1 for backward compatibility. Application should set it to
270 0 to disable critical sections from unprivileged tasks.
272 Changes between FreeRTOS V10.4.4 and FreeRTOS V10.4.5 released September 10 2021
274 See https://www.FreeRTOS.org/FreeRTOS-V10.4.5.html
276 + Introduce configRUN_TIME_COUNTER_TYPE which enables developers to define
277 the type used to hold run time statistic counters. Defaults to uint32_t
278 for backward compatibility. #define configRUN_TIME_COUNTER_TYPE to a type
279 (for example, uint64_t) in FreeRTOSConfig.h to override the default.
280 + Introduce ulTaskGetIdleRunTimePercent() to complement the pre-existing
281 ulTaskGetIdleRunTimeCounter(). Whereas the pre-existing function returns
282 the raw run time counter value, the new function returns the percentage of
283 the entire run time consumed by the idle task. Note the amount of idle
284 time is only a good measure of the slack time in a system if there are no
285 other tasks executing at the idle priority, tickless idle is not used, and
286 configIDLE_SHOULD_YIELD is set to 0.
287 + ARMv8-M secure-side port: Tasks that call secure functions from the
288 non-secure side of an ARMv8-M MCU (ARM Cortex-M23 and Cortex-M33) have two
289 contexts - one on the non-secure side and one on the secure-side. Previous
290 versions of the FreeRTOS ARMv8-M secure-side ports allocated the structures
291 that reference secure-side contexts at run time. Now the structures are
292 allocated statically at compile time. The change necessitates the
293 introduction of the secureconfigMAX_SECURE_CONTEXTS configuration constant,
294 which sets the number of statically allocated secure contexts.
295 secureconfigMAX_SECURE_CONTEXTS defaults to 8 if left undefined.
296 Applications that only use FreeRTOS code on the non-secure side, such as
297 those running third-party code on the secure side, are not affected by
300 Changes between FreeRTOS V10.4.3 and FreeRTOS V10.4.4 released May 28 2021
301 + Minor performance improvements to xTaskIncrementTick() achieved by providing
302 macro versions of uxListRemove() and vListInsertEnd().
303 + Minor refactor of timers.c that obsoletes the need for the
304 tmrCOMMAND_START_DONT_TRACE macro and removes the need for timers.c to
305 post to its own event queue. A consequence of this change is that auto-
306 reload timers that miss their intended next execution time will execute
307 again immediately rather than executing again the next time the command
308 queue is processed. (thanks Jeff Tenney).
309 + Fix a race condition in the message buffer implementation. The
310 underlying cause was that length and data bytes are written and read as
311 two distinct operations, which both modify the size of the buffer. If a
312 context switch occurs after adding or removing the length bytes, but
313 before adding or removing the data bytes, then another task may observe
314 the message buffer in an invalid state.
315 + The xTaskCreate() and xTaskCreateStatic() functions accept a task priority
316 as an input parameter. The priority has always been silently capped to
317 (configMAX_PRIORITIES - 1) should it be set to a value above that priority.
318 Now values above that priority will also trigger a configASSERT() failure.
319 + Replace configASSERT( pcQueueName ) in vQueueAddToRegistry with a NULL
321 + Introduce the configSTACK_ALLOCATION_FROM_SEPARATE_HEAP configuration
322 constant that enables the stack allocated to tasks to come from a heap other
323 than the heap used by other memory allocations. This enables stacks to be
324 placed within special regions, such as fast tightly coupled memory.
325 + If there is an attempt to add the same queue or semaphore handle to the
326 queue registry more than once then prior versions would create two separate
327 entries. Now if this is done the first entry is overwritten rather than
329 + Update the ESP32 port and TF-M (Trusted Firmware M)code to the latest from
330 their respective repositories.
331 + Correct a build error in the POSIX port.
332 + Additional minor formatting updates, including replacing tabs with spaces
334 + Other minor updates include adding additional configASSERT() checks and
335 correcting and improving code comments.
336 + Go look at the smp branch to see the progress towards the Symetric
337 Multiprocessing Kernel. https://github.com/FreeRTOS/FreeRTOS-Kernel/tree/smp
339 Changes between FreeRTOS V10.4.2 and FreeRTOS V10.4.3 released December 14 2020
341 V10.4.3 is included in the 202012.00 LTS release. Learn more at https:/freertos.org/lts-libraries.html
343 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
345 + Changes to improve robustness and consistency for buffer allocation in
346 the heap, queue and stream buffer.
347 + The following functions can no longer be called from unprivileged code.
348 - xTaskCreateRestricted
349 - xTaskCreateRestrictedStatic
350 - vTaskAllocateMPURegions
353 Changes between FreeRTOS V10.4.1 and FreeRTOS V10.4.2 released November 10 2020
355 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
357 + Fix an issue in the ARMv8-M ports that caused BASEPRI to be masked
358 between the first task starting to execute and that task making
360 + Introduced xTaskDelayUntil(), which is functionally equivalent to
361 vTaskDelayUntil(), with the addition of returning a value to
362 indicating whether or not the function placed the calling task into
363 the Blocked state or not.
364 + Update WolfSSL to 4.5.0 and add the FIPS ready demo.
365 + Add support for ESP IDF 4.2 to ThirdParty Xtensa port.
366 + Re-introduce uxTopUsedPriority to support OpenOCD debugging.
367 + Convert most dependent libraries in FreeRTOS/FreeRTOS to submodules.
368 + Various general maintenance and improvements to MISRA compliance.
371 Changes between FreeRTOS V10.4.0 and FreeRTOS V10.4.1 released September 17 2020
373 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
375 + Fixed an incorrectly named parameter that prevented the
376 ulTaskNotifyTakeIndexed macro compiling, and the name space clash in the
377 test code that prevented this error causing test failures.
380 Changes between FreeRTOS V10.3.1 and FreeRTOS V10.4.0 released September 10 2020
382 See https://www.FreeRTOS.org/FreeRTOS-V10.4.x.html
386 + Task notifications: Prior to FreeRTOS V10.4.0 each created task had a
387 single direct to task notification. From FreeRTOS V10.4.0 each task has
388 an array of notifications. The direct to task notification API has been
389 extended with API functions postfixed with "Indexed" to enable the API to
390 operate on a task notification at any array index. See
391 https://www.freertos.org/RTOS-task-notifications.html for more information.
392 + Kernel ports that support memory protection units (MPUs): The ARMv7-M and
393 ARMv8-M MPU ports now support a privilege access only heap. The ARMv7-M
394 MPU ports now support devices that have 16 MPU regions, have the ability
395 to override default memory attributes for privileged code and data
396 regions, and have the ability to place the FreeRTOS kernel code outside of
397 the Flash memory. The ARMv8-M MPU ports now support tickless idle mode.
398 See https://www.freertos.org/FreeRTOS-MPU-memory-protection-unit.html
399 for more information.
401 Additional noteworthy updates:
403 + Code formatting is now automated to facilitate the increase in
404 collaborative development in Git. The auto-formated code is not identical
405 to the original formatting conventions. Most notably spaces are now used
407 + The prototypes for callback functions (those that start with "Application",
408 such as vApplicationStackOverflowHook()) are now in the FreeRTOS header
409 files, removing the need for application writers to add prototypes into
410 the C files in which they define the functions.
411 + New Renesas RXv3 port layer.
412 + Updates to the Synopsys ARC code, including support for EM and HS cores,
414 + Added new POSIX port layer that allows FreeRTOS to run on Linux hosts in
415 the same way the Windows port layer enables FreeRTOS to run on Windows
417 + Many other minor optimisations and enhancements. For full details
418 see https://github.com/FreeRTOS/FreeRTOS-Kernel/commits/main
421 Changes between FreeRTOS V10.3.0 and FreeRTOS V10.3.1 released February 18 2020
423 See https://www.FreeRTOS.org/FreeRTOS-V10.3.x.html
425 + ./FreeRTOS-Labs directory was removed from this file. The libraries it
426 contained are now available as a separate download.
428 Changes between FreeRTOS V10.2.1 and FreeRTOS V10.3.0 released February 7 2020
430 See https://www.FreeRTOS.org/FreeRTOS-V10.3.x.html
432 New and updated kernel ports:
434 + Added RISC-V port for the IAR compiler.
435 + Update the Windows simulator port to use a synchronous object to prevent
436 a user reported error whereby a task continues to run for a short time
437 after being moved to the Blocked state. Note we were not able to
438 replicate the reported issue and it likely depends on your CPU model.
439 + Correct alignment of stack top in RISC-V port when
440 configISR_STACK_SIZE_WORDS is defined to a non zero value, which causes
441 the interrupt stack to be statically allocated.
442 + The RISC-V machine timer compare register can now be for any HART, whereas
443 previously it was always assumed FreeRTOS was running on HART 0.
444 + Update the sequence used to update the 64-bit machine timer
445 compare register on 32-bit cores to match that suggested in RISC-V
447 + Added tickless low power modes into the ARM, IAR and GCC Cortex-M0 compiler
449 + Updated the behaviour of the ARMv7-M MPU (Memory Protection Unit) ports to
450 match that of the ARMv8-M ports whereby privilege escalations can only
451 originate from within the kernel's own memory segment. Added
452 configENFORCE_SYSTEM_CALLS_FROM_KERNEL_ONLY configuration constant.
453 + Update existing MPU ports to correctly disable the MPU before it is
455 + Added contributed port and demo application for a T-Head (formally C-SKY)
460 + Added the vPortGetHeapStats() API function which returns information on
461 the heap_4 and heap_5 state.
462 + Added xTaskCatchUpTicks(), which corrects the tick count value after the
463 application code has held interrupts disabled for an extended period.
464 + Added xTaskNotifyValueClear() API function.
465 + Added uxTimerGetReloadMode() API function.
467 Other miscellaneous changes:
468 + Change type of uxPendedTicks from UBaseType_t to TickType_t to ensure it
469 has the same type as variables with which it is compared to, and therefore
470 also renamed the variable xPendingTicks.
471 + Update Keil projects that use the MPU so memory regions come from linker
472 script (scatter file) variables instead of being hard coded.
473 + Added LPC51U68 Cortex-M0+ demos for GCC (MCUXpresso), Keil and IAR
475 + Added CORTEX_MPU_STM32L4_Discovery_Keil_STM32Cube demo.
476 + Added LPC54018 MPU demo.
477 + Rename xTaskGetIdleRunTimeCounter() to ulTaskGetIdleRunTimeCounter().
480 Changes between FreeRTOS V10.2.1 and FreeRTOS V10.2.0 released May 13 2019:
482 + Added ARM Cortex-M23 port layer to complement the pre-existing ARM
483 Cortex-M33 port layer.
484 + The RISC-V port now automatically switches between 32-bit and 64-bit
486 + Introduced the portMEMORY_BARRIER macro to prevent instruction re-ordering
487 when GCC link time optimisation is used.
488 + Introduced the portDONT_DISCARD macro to the ARMv8-M ports to try and
489 prevent the secure side builds from removing symbols required by the
490 non secure side build.
491 + Introduced the portARCH_NAME to provide additional data to select semi-
492 automated build environments.
493 + Cortex-M33 and Cortex-M23 ports now correctly disable the MPU before
494 updating the MPU registers.
496 + Added Nuvoton NuMaker-PFM-M2351 ARM Cortex-M23 demo.
497 + Added LPC55S69 ARM Cortex-M33 demo.
498 + Added an STM32 dual core AMP stress test demo.
501 Changes between FreeRTOS V10.1.1 and FreeRTOS V10.2.0 released February 25 2019:
503 + Added GCC RISC-V MCU port with three separate demo applications.
504 + Included pre-existing ARM Cortex-M33 (ARMv8-M) GCC/ARMclang and IAR ports
505 with Keil simulator demo.
506 + Update the method used to detect if a timer is active. Previously the
507 timer was deemed to be inactive if it was not referenced from a list.
508 However, when a timer is updated it is temporarily removed from, then
509 re-added to a list, so now the timer's active status is stored separately.
510 + Add vTimerSetReloadMode(), xTaskGetIdleRunTimeCounter(), and
511 xTaskGetApplicationTaskTagFromISR() API functions.
512 + Updated third party Xtensa port so it is MIT licensed.
513 + Added configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H to the Renesas
514 compiler RX600v2 port to enable switching between platform.h and
515 iodefine.h includes within that port's port.c file.
516 + Removed the 'FromISR' functions from the MPU ports as ISRs run privileged
518 + Added uxTaskGetStackHighWaterMark2() function to enable the return type to
519 be changed without breaking backward compatibility.
520 uxTaskGetStackHighWaterMark() returns a UBaseType_t as always,
521 uxTaskGetStackHighWaterMark2() returns configSTACK_DEPTH_TYPE to allow the
522 user to determine the return type.
523 + Fixed issues in memory protected ports related to different combinations
524 of static memory only and dynamic memory only builds. As a result the
525 definition of tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE became more
526 complex and was moved to FreeRTOS.h with a table explaining its definition.
527 + Added a 'get task tag from ISR' function.
528 + Change the method used to determine if a timer is active or not from just
529 seeing if it is referenced from the active timer list to storing its
530 active state explicitly. The change prevents the timer reporting that it
531 is inactive while it is being moved from one list to another.
532 + The pcName parameter passed into the task create functions can be NULL,
533 previously a name had to be provided.
534 + When using tickless idle, prvResetNextTaskUnblockTime() is now only called
535 in xTaskRemoveFromEventList() if the scheduler is not suspended.
536 + Introduced portHAS_STACK_OVERFLOW_CHECKING, which should be set to 1 for
537 FreeRTOS ports that run on architectures that have stack limit registers.
540 Changes between FreeRTOS V10.1.0 and FreeRTOS V10.1.1 released 7 September 2018
542 + Reverted a few structure name changes that broke several kernel aware
544 + Updated to the latest trace recorder code.
545 + Fixed some formatting in the FreeRTOS+TCP TCP/IP stack code.
546 + Reverted moving some variables from file to function scope as doing so
547 broke debug scenarios that require the static qualifier to be removed.
549 Changes between FreeRTOS V10.0.1 and FreeRTOS V10.1.0 released 22 August 2018
551 FreeRTOS Kernel Changes:
553 + Update lint checked MISRA compliance to use the latest MISRA standard, was
554 previously using the original MISRA standard.
555 + Updated all object handles (TaskHandle_t, QueueHandle_t, etc.) to be
556 unique types instead of void pointers, improving type safety. (this was
557 attempted some years back but had to be backed out due to bugs in some
558 debuggers). Note this required the pvContainer member of a ListItem_t
559 struct to be renamed - set configENABLE_BACKWARD_COMPATIBILITY to 1 if
560 this causes an issue.
561 + Added configUSE_POSIX_ERRNO to enable per task POSIX style errno
562 functionality in a more user friendly way - previously the generic thread
563 local storage feature was used for this purpose.
564 + Added Xtensa port and demo application for the XCC compiler.
565 + Changed the implementation of vPortEndScheduler() for the Win32 port to
566 simply call exit( 0 ).
567 + Bug fix in vPortEnableInterrupt() for the GCC Microblaze port to protect
568 the read modify write access to an internal Microblaze register.
569 + Fix minor niggles when the MPU is used with regards to prototype
570 differences, static struct size differences, etc.
571 + The usStackHighWaterMark member of the TaskStatus_t structure now has type
572 configSTACK_DEPTH_TYPE in place of uint16_t - that change should have been
573 made when the configSTACK_DEPTH_TYPE type (which gets around the previous
574 16-bit limit on stack size specifications) was introduced.
575 + Added the xMessageBufferNextLengthBytes() API function and likewise stream
577 + Introduce configMESSAGE_BUFFER_LENGTH_TYPE to allow the number of bytes
578 used to hold the length of a message in the message buffer to be reduced.
579 configMESSAGE_BUFFER_LENGTH_TYPE default to size_t, but if, for example,
580 messages can never be more than 255 bytes it could be set to uint8_t,
581 saving 3 bytes each time a message is written into the message buffer
582 (assuming sizeof( size_t ) is 4).
583 + Updated the StaticTimer_t structure to ensure it matches the size of the
584 Timer_t structure when the size of TaskFunction_t does not equal the size
586 + Update various Xilinx demos to use 2018.1 version of the SDK tools.
587 + Various updates to demo tasks to maintain test coverage.
588 + FreeRTOS+UDP was removed in FreeRTOS V10.1.0 as it was replaced by
589 FreeRTOS+TCP, which was brought into the main download in FreeRTOS
590 V10.0.0. FreeRTOS+TCP can be configured as a UDP only stack, and
591 FreeRTOS+UDP does not contain the patches applied to FreeRTOS+TCP.
593 FreeRTOS+TCP Changes:
595 + Multiple security improvements and fixes in packet parsing routines, DNS
596 caching, and TCP sequence number and ID generation.
597 + Disable NBNS and LLMNR by default.
598 + Add TCP hang protection by default.
600 We thank Ori Karliner of Zimperium zLabs Team for reporting these issues.
603 Changes between FreeRTOS V10.0.0 and FreeRTOS V10.0.1, released December 20 2017
605 + Fix position of "#if defined( __cplusplus )" in stream_buffer.h.
606 + Correct declarations of MPU_xQueuePeek() and MPU_xQueueSemaphoreTake() in
608 + Correct formatting in vTaskList() helper function when it prints the state
609 of the currently executing task.
610 + Introduce #error if stream_buffer.c is built without
611 configUSE_TASK_NOTIFICATIONS set to 1.
612 + Update FreeRTOS+TCP to V2.0.0
613 - Improve the formatting of text that displays the available netword
614 interfaces when FreeRTOS+TCP is used on Windows with WinPCap.
615 - Introduce ipconfigSOCKET_HAS_USER_WAKE_CALLBACK option to enable a user
616 definable callback to execute when data arrives on a socket.
618 Changes between FreeRTOS V9.0.1 and FreeRTOS V10.0.0:
620 The FreeRTOS kernel is now MIT licensed: https://www.FreeRTOS.org/license
622 New Features and components:
624 + Stream Buffers - see https://www.FreeRTOS.org/RTOS-stream-buffer-example.html
625 + Message Buffers - see https://www.FreeRTOS.org//RTOS-message-buffer-example.html
626 + Move FreeRTOS+TCP into the main repository, along with the basic Win32
627 TCP demo FreeRTOS_Plus_TCP_Minimal_Windows_Simulator.
631 + Added demo for TI SimpleLink CC3220 MCU.
632 + Added MPU and non MPU projects for Microchip CEC and MEC 17xx and 51xx
634 + Added CORTEX_MPU_Static_Simulator_Keil_GCC demo to test static allocation
637 Fixes or enhancements:
639 + Cortex-M ports push additional register prior to calling
640 vTaskSwitchContext to ensure 8-byte alignment is maintained. Only
641 important if a user defined tick hook function performs an operation that
642 requires 8-byte alignment.
643 + Optimisations to the implementation of the standard tickless idle mode on
645 + Improvements to the Win32 port including using higher priority threads.
646 + Ensure interrupt stack alignment on PIC32 ports.
647 + Updated GCC TriCore port to build with later compiler versions.
648 + Update mpu_wrappers.c to support static allocation.
649 + The uxNumberOfItems member of List_t is now volatile - solving an issue
650 when the IAR compiler was used with maximum optimization.
651 + Introduced configRECORD_STACK_HIGH_ADDRESS. When set to 1 the stack start
652 address is saved into each task's TCB (assuming stack grows down).
653 + Introduced configINCLUDE_FREERTOS_TASK_C_ADDITIONS_H to allow user defined
654 functionality, and user defined initialisation, to be added to FreeRTOS's
655 tasks.c source file. When configINCLUDE_FREERTOS_TASK_C_ADDITIONS_H is
656 set to 1 a user provided header file called freertos_task_c_additions.h
657 will be included at the bottom of tasks.c. Functions defined in that
658 header file can call freertos_tasks_c_additions_init(), which in turn
659 calls a macro called FREERTOS_TASKS_C_ADDITIONS_INIT(), if it is defined.
660 FREERTOS_TASKS_C_ADDITIONS_INIT() can be defined in FreeRTOSConfig.h.
661 + Introduced configPRE_SUPPRESS_TICKS_AND_SLEEP_PROCESSING( x ) which can be
662 defined by a user in FreeRTOSConfig.h. The macro is called before
663 assessing whether to enter tickless idle mode or not. If the macro sets
664 x to zero then tickless idle mode will not be entered. This allows users
665 to abort tickless idle mode entry before the tickless idle function is
666 even called - previously it was only possible to abort from within the
667 tickless idle function itself.
668 + Added configPRINTF(), which can be defined by users to allow all libraries
669 to use the same print formatter.
670 + Introduced configMAX() and configMIN() macros which default to standard
671 max( x, y ) and min( x, y ) macro behaviour, but can be overridden if the
672 application writer defines the same macros in FreeRTOSConfig.h.
673 + Corrected the definition of StaticTask_t in the case where
674 INCLUDE_xTaskAbortDelay is set to 1.
675 + Introduced configTIMER_SERVICE_TASK_NAME and configIDLE_TASK_NAME, both of
676 which can be defined to strings in FreeRTOSConfig.h to change the default
677 names of the timer service and idle tasks respectively.
678 + Only fill the stack of a newly created task with a known value if stack
679 checking, or high water mark checking/viewing, is in use - removing the
680 dependency on memset() in other cases.
681 + Introduced xTaskCreateRestrictedStatic() so static allocation can be used
683 + Ensure suspended tasks cannot be unsuspended by a received task
685 + Fix race condition in vTaskSetTimeOutState().
686 + Updated trace recorder files to the latest version.
688 Changes since FreeRTOS V9.0.0:
690 + Priority dis-inheritance behaviour has been enhanced in the case where a
691 task that attempted to take a mutex that was held by a lower priority task
692 timed out before it was able to obtain the mutex (causing the task that
693 holds the mutex to have its priority raised, then lowered again, in
694 accordance with the priority inheritance protocol).
695 + Split the overloaded xQueueGenericReceive() function into three separate
697 + Allow the default human readable text names given to the Idle and Timer
698 tasks to be overridden by defining the configIDLE_TASK_NAME and
699 configTIMER_SERVICE_TASK_NAME definitions respectively in FreeRTOSConfig.h.
700 + Introduced configINITIAL_TICK_COUNT to allow the tick count to take a
701 value of than than 0 when the system boots. This can be useful for
702 testing purposes - although setting configUSE_16_BIT_TICKS to 1 can also
703 be used to test frequent tick overflows.
704 + Ensure the Cortex-M SysTick count is cleared to zero before starting the
706 + Add configASSERT() into ARM Cortex-M ports to check the number of priority
708 + Clear the 'control' register before starting ARM Cortex-M4F ports in case
709 the FPU is used before the scheduler is started. This just saves a few
710 bytes on the main stack as it prevents space being left for a later save
712 + Added xSemaphoreGetMutexHolderFromISR().
713 + Corrected use of portNVIC_PENDSVSET to portNVIC_PENDSVSET_BIT in MPU ports.
714 + Introduced configSTACK_DEPTH_TYPE to allow users to change the type used
715 to specify the stack size when using xTaskCreate(). For historic reasons,
716 when FreeRTOS was only used on small MCUs, the type was set to uint16_t,
717 but that can be too restrictive when FreeRTOS is used on larger
718 processors. configSTACK_DEPTH_TYPE defaults to uint16_t.
719 xTaskCreateStatic(), being a newer function, used a uint32_t.
720 + Increase the priority of the Windows threads used by the Win32 port. As
721 all the threads run on the same core, and the threads run with very high
722 priority, there is a risk that the host will become unresponsive, so also
723 prevent the Windows port executing on single core hosts.
725 Changes between FreeRTOS V9.0.0 and FreeRTOS V9.0.0rc2 released May 25 2016:
727 See https://www.FreeRTOS.org/FreeRTOS-V9.html
731 + The prototype of the new xTaskCreateStatic() API function was modified to
732 remove a parameter and improve compatibility with other new
733 "CreateStatic()" API functions. The stack size parameter in
734 xTaskCreateStatic() is now uint32_t, which changes the prototype of the
735 callback functions. See the following URL:
736 https://www.FreeRTOS.org/xTaskCreateStatic.html
737 + GCC ARM Cortex-A port: Introduced the configUSE_TASK_FPU_SUPPORT
738 constant. When configUSE_TASK_FPU_SUPPORT is set to 2 every task is
739 automatically given a floating point (FPU) context.
740 + GCC ARM Cortex-A port: It is now possible to automatically save and
741 restore all floating point (FPU) registers on entry to each potentially
742 nested interrupt by defining vApplicationFPUSafeIRQHandler() instead of
743 vApplicationIRQHandler().
744 + All ARM Cortex-M3/4F/7 ports: Clear the least significant bit of the task
745 entry address placed onto the stack of a task when the task is created for
746 strict compliance with the ARM Cortex-M3/4/7 architecture documentation
747 (no noticeable effect unless using the QMEU emulator).
748 + Added GCC and Keil ARM Cortex-M4F MPU ports - previously the MPU was only
749 supported on ARM Cortex-M3.
750 + ARM Cortex-M3/4F MPU ports: Update to fully support the FreeRTOS V9.0.0
751 API (other than static object creation) and added the
752 FreeRTOS/Demo/CORTEX_MPU_Simulator_Keil_GCC demo application to
753 demonstrate how to use the updated MPU port.
754 + All ARM Cortex-M3/4F/7 ports: Add additional barrier instructions to the
755 default low power tickless implementation.
756 + All ARM Cortex-M0 ports: Prevent an item being left on the stack of the
757 first task that executes.
758 + Win32 ports: Reduce the amount of stack used and change the way Windows
759 threads are deleted to increase the maximum execution time.
760 + Add an ARM Cortex-M4F port for the MikroC compiler. Ensure to read the
761 documentation page for this port before use.
762 + MPS430X IAR port: Update to be compatible with the latest EW430 tools
764 + IAR32 GCC port: Correct vPortExitCritical() when
765 configMAX_API_CALL_INTERRUPT_PRIORITY == portMAX_PRIORITY.
766 + For consistency vTaskGetTaskInfo() now has the alias vTaskGetInfo(),
767 xTaskGetTaskHandle() now has the alias xTaskGetHandle() and
768 pcQueueGetQueueName() now has an alias pcQueueGetName().
769 + Fix various errors in comments and compiler warnings.
771 Demo application updates:
773 + Update Atmel Studio projects to use Atmel Studio 7.
774 + Update Xilinx SDK projects to use the 2016.1 version of the SDK.
775 + Remove dependency on legacy IO libraries from the PIC32 demos.
776 + Move the Xilinx UltraScale Cortex-R5 demo into the main distribution.
777 + Update the MSP432 libraries to the latest version.
778 + Add Microchip CEC1302 (ARM Cortex-M4F) demos for GCC, Keil and MikroC
780 + Move the Atmel SAMA5D2 demo into the main distribution.
782 Changes between FreeRTOS V9.0.0rc1 and FreeRTOS V9.0.0rc2 (release candidate 2)
783 released March 30 2016:
785 NOTE - See https://www.FreeRTOS.org/FreeRTOS-V9.html for details
787 + The functions that create RTOS objects using static memory allocation have
788 been simplified and will not revert to using dynamic allocation if a
789 buffer is passed into a function as NULL.
790 + Introduced the configSUPPORT_DYNAMIC_ALLOCATION configuration constant to
791 allow a FreeRTOS application to be built without a heap even being being
792 defined. The Win32 example located in the
793 /FreeRTOS/demo/WIN32-MSVC-Static-Allocation-Only directory is provided as
794 a reference for projects that do not include a FreeRTOS heap.
795 + Minor run-time optimisations.
796 + Two new low power tickless implementations that target Silicon Labs EFM32
798 + Addition of the xTimerGetPeriod() and xTimerGetExpireTime() API functions.
800 Changes between FreeRTOS V8.2.3 and FreeRTOS V9.0.0rc1 (release candidate 1)
801 released February 19 2016:
805 + Major new feature - tasks, semaphores, queues, timers and event groups can
806 now be created using statically allocated memory, so without any calls to
808 + Major new features - Added the xTaskAbortDelay() API function which allows
809 one task to force another task to immediately leave the Blocked state,
810 even if the event the blocked task is waiting for has not occurred, or the
811 blocked task's timeout has not expired.
812 + Updates necessary to allow FreeRTOS to run on 64-bit architectures.
813 + Added vApplicationDaemonTaskStartupHook() which executes when the RTOS
814 daemon task (which used to be called the timer service task) starts
815 running. This is useful if the application includes initialisation code
816 that would benefit from executing after the scheduler has been started.
817 + Added the xTaskGetTaskHandle() API function, which obtains a task handle
818 from the task's name. xTaskGetTaskHandle() uses multiple string compare
819 operations, so it is recommended that it is called only once per task.
820 The handle returned by xTaskGetTaskHandle() can then be stored locally for
822 + Added the pcQueueGetQueueName() API function, which obtains the name of
823 a queue from the queue's handle.
824 + Tickless idling (for low power applications) can now also be used when
825 configUSE_PREEMPTION is 0.
826 + If one task deletes another task, then the stack and TCB of the deleted
827 task is now freed immediately. If a task deletes itself, then the stack
828 and TCB of the deleted task are freed by the Idle task as before.
829 + If a task notification is used to unblock a task from an ISR, but the
830 xHigherPriorityTaskWoken parameter is not used, then pend a context switch
831 that will then occur during the next tick interrupt.
832 + Heap_1.c and Heap_2.c now use the configAPPLICATION_ALLOCATED_HEAP
833 settings, which previously was only used by heap_4.c.
834 configAPPLICATION_ALLOCATED_HEAP allows the application writer to declare
835 the array that will be used as the FreeRTOS heap, and in-so-doing, place
836 the heap at a specific memory location.
837 + TaskStatus_t structures are used to obtain details of a task.
838 TaskStatus_t now includes the bae address of the task's stack.
839 + Added the vTaskGetTaskInfo() API function, which returns a TaskStatus_t
840 structure that contains information about a single task. Previously this
841 information could only be obtained for all the tasks at once, as an array
842 of TaskStatus_t structures.
843 + Added the uxSemaphoreGetCount() API function.
844 + Replicate previous Cortex-M4F and Cortex-M7 optimisations in some
845 Cortex-M3 port layers.
847 Demo Application Updates:
849 Further demo applications will be added prior to the final FreeRTOS V9
852 + Updated SAM4L Atmel Studio project to use Atmel Studio 7.
853 + Added ARM Cortex-A53 64-bit port.
854 + Added a port and demo for the ARM Cortex-A53 64-bit cores on the Xilinx
856 + Added Cortex-M7 SAME70 GCC demo.
857 + Added EFM32 Giant and Wonder Gecko demos.
860 Changes between V8.2.2 and V8.2.3 released October 16, 2015
864 + Fix bug identified in a modification made in V8.2.2 to the software timer
865 code that allows tickless low power applications to sleep indefinitely
866 when software timers are used.
867 + Simplify and improve efficiency of stack overflow checking.
868 + Add xTaskNotifyStateClear() API function.
869 + New IAR and GCC Cortex-R ports for microprocessors that do not use an ARM
870 generic interrupt controller (GIC).
871 + New PIC32MEC14xx port.
872 + Add support for PIC32MZ EF parts (with floating point) into the PIC32MZ
874 + Zynq7000 port layer now declares the functions that setup and clear the
875 tick interrupt as weak symbols so they can be overridden by the
876 application, and uses a global XScuGic object so the same object can be
877 used by the application code.
878 + Introduced configUSE_TASK_FPU_SUPPORT, although the PIC32MZ EF port is
879 currently the only port that uses it.
880 + Updates to RL78 and 78K0 IAR port layers to improve support for
881 combinations of memory models.
882 + Minor updates to heap_5.c to remove compiler warnings generated by some
884 + License simplifications. See /FreeRTOS/License/license.txt in the
885 official distribution.
889 + Update directory names to use WolfSSL instead of CyaSSL, inline with
890 WolfSSL's re-branding.
891 + Update to latest WolfSSL code.
892 + Update to latest FreeRTOS+Trace recorder code.
893 + Add in the FreeRTOS+Trace recorder library required for streaming trace.
895 Demo application changes:
897 + Add demo applications for Renesas RZ/T (Cortex-R), PIC32MZ EF (PIC32 with
898 floating point hardware), PIC32MEC14xx, RX71M, RX113 and RX231.
899 + General tidy up of spelling and compiler warnings.
902 Changes between V8.2.1 and V8.2.2 released August 12, 2015
906 + Added Intel IA32/x86 32-bit port.
907 + General maintenance.
908 + PRIVILEGED_FUNCTION and PRIVILEGED_DATA macros, which are used in memory
909 protected systems, have been added to the newer event group and software
911 + Add the errno definitions used by FreeRTOS+ components into projdefs.h.
912 + Remove the restriction that prevented tick-less idle implementations
913 waiting indefinitely when software timers were used in the same
915 + Introduce xTaskNotifyAndQueryFromISR() as the interrupt safe version of
916 xTaskNotifyAndQuery().
917 + Add additional NOPs to the MSP430X port layers to ensure strict compliance
918 with the hardware documentation.
919 + Microblaze port: Added option for port optimised task selection.
920 + Microblaze port: Previously tasks inherited the exception enable state
921 at the time the task was created. Now all tasks are created with
922 exceptions enabled if the Microblaze design supports exceptions.
923 + Windows port: Add additional safe guards to ensure the correct start up
924 sequence and thread switching timing.
925 + Windows port: Improve the implementation of the port optimised task
926 selection assembly code.
927 + Update heap_4 and heap_5 to allow use on 64-bit processors.
928 + Simplify the code that creates a queue.
929 + General improved tick-less idle behaviour.
930 + Ensure none of the variables in the common kernel files are initialised to
931 anything other than zero.
932 + Correct calculation of xHeapStructSize in heap_4 and heap_5.
934 Demo application updates:
936 + Added demo project for the new IA32/x86 port that targets the Galileo
938 + Added MSP430FR5969 demos (previously provided as a separate download).
939 + Added FreeRTOS BSP repository for automatic creation of FreeRTOS
940 applications in the Xilinx SDK.
941 + Added Atmel Studio / GCC project for the SAMV71 (ARM Cortex-M7)
942 + Update Xilinx SDK projects to use version 2015.2 of the SDK.
943 + Remove Microblaze demos that were using obsolete tools.
944 + Add MSP43FR5969 IAR and CCS demos.
948 + Updated FreeRTOS+Trace recorder library, which requires an update to the
949 FreeRTOS+Trace application.
950 + Added Reliance Edge source code and demo application. Reliance edge is
951 a fail safe transactional file system ideal for applications that require
952 file storage, and especially when high reliability is essential.
953 + Introduce configAPPLICATION_PROVIDES_cOutputBuffer to allow FreeRTOS+CLI
954 users to place the output buffer at a fixed memory address.
955 + Improve the NetworkInterface.c file provided for the Windows port of
958 Changes between V8.2.0 and V8.2.1 released 24th March 2015.
962 + Added user definable and flexible thread local storage facility.
963 + Added vTimerSetTimerID() API function to complement the pvTimerGetTimerID()
964 function to allow the timer's ID to be used as timer local storage.
965 + Fixed a potential issue related to the use of queue sets from an ISR.
966 + Some updates to the Xilinx Microblaze GCC port.
967 + Added ARM Cortex-M4F port for Texas Instruments Code Composer Studio.
968 + Added ARM Cortex-M7 r0p1 port layer for IAR, GCC and Keil which contains a
969 minor errata work around. All other ARM Cortex-M7 core revisions should
970 use the ARM Cortex-M4F port.
971 + Exclude the whole of croutine.c if configUSE_CO_ROUTINES is set to 0.
972 + Change some data types from uint32_t to size_t in preparation for 64-bit
974 + Update the PIC32 port to remove deprecation warnings output by the latest
976 + Fix bug when xQueueOverwrite() and xQueueOverwrite() from ISR are used to
977 overwrite items in two queues that are part of the same set.
979 Demo application updates:
981 + Added demo application for TI's ARM Cortex-M4F based MSP432
982 microcontroller using IAR, Keil and CCS compilers.
983 + Added demo application for STM32F ARM Cortex-M7 based microcontroller
985 + Added demo application for Atmel SAMV71 ARM Cortex-M7 based
986 microcontroller using IAR and Keil.
987 + Added Microblaze demo that uses the 2014.4 version of the Xilinx SDK and
988 runs on the KC705 evaluation board (Kintex FPGA).
990 Changes between V8.1.2 and V8.2.0 released 16th January 2015
992 Changes between release candidate 1 and the official release are restricted
995 Significant RTOS kernel updates:
997 + MAJOR NEW FEATURE! Task notifications. Please see the following URL for
998 details: https://www.FreeRTOS.org/RTOS-task-notifications.html
999 + NEW HEADER FILE REQUIRED! Obsolete definitions have been separated into
1000 a new header file called FreeRTOS/Source/include/deprecated_definitions.h.
1001 This header file must be present to build. Note some of the obsolete
1002 definitions are still used by very old demo application projects.
1004 Other RTOS kernel updates:
1006 + Made xSemaphoreGiveFromISR() a function rather than a macro that calls
1007 xQueueGenericSendFromISR(). This allows for major performance
1008 enhancements at the expense of some additional code size if both functions
1009 are used in the same application. NOTE: In most uses cases such use of
1010 a semaphore can now be replaced with a task notification which is smaller
1012 + The TCB is now always allocated such that the task's stack grows away from
1013 the TCB (improves debugging of stack overflows as the overflow will not
1014 overwrite the task's name).
1015 + GCC, IAR and Keil Cortex-M4F ports now use more inlining (performance
1016 enhancements at the cost of a little additional code space).
1017 + Queues are now allocated with a single call to pvPortMalloc() which
1018 allocates both the queue structure and the queue storage area.
1019 + Introduced a new critical section macro for reading the tick count that
1020 defines away to nothing in cases where the width of the tick allows the
1021 tick count to be read atomically (performance benefits - especially when
1022 optimisation is on).
1023 + Introduced configAPPLICATION_ALLOCATED_HEAP in heap_4.c to allow the
1024 application writer to provide their own heap array - and in so doing
1025 control the location of the heap.
1026 + Introduced configUSE_LIST_DATA_INTEGRITY_CHECK_BYTES which, when set, will
1027 include known values in both list and list item structures. The values
1028 are intended to assist debugging. If the values get overwritten then it
1029 is likely application code has written over RAM used by the kernel.
1030 + configASSERT()s in all Cortex-M ports used to test the lowest 5 bits of
1031 the interrupt control register to detect taskENTER_CRITICAL() being called
1032 from an interrupt. This has been changed to test all 8 bits.
1033 + Introduced uxTaskPriorityGetFromISR().
1034 + Microblze V8 port now tests XPAR_MICROBLAZE_0_USE_FPU for inequality to 0
1035 rather than equality to 1, and 2 and 3 are also valid values.
1036 + Cortex-A5 GIC-less port no longer passes the address of the interrupting
1037 peripheral into the interrupt handler.
1038 + Fix an issue in FreeRTOS-MPU where an attempt was made to free the stack
1039 belonging to a task when the task was deleted, even when the stack was
1040 allocated statically.
1041 + Utility (helper) functions that format task statistic information into
1042 human readable tables now pad task names with spaces to ensure columns
1043 line up correctly even where task name lengths vary greatly.
1044 + Update FreeRTOS+Trace recorder library to version 2.7.0.
1046 Demo application updates:
1048 + Added two new standard demo task sets: IntSemTest and TaskNotify.
1049 + Added port and demo application for Atmel SAMA5D4 Cortex-A5 MPU.
1050 + Added demo application for Altera Cyclone V Cortex-A9 MPU.
1051 + Updated Zynq demo to use version 2014.4 of Xilinx's SDK and added in
1052 demo tasks for new RTOS features.
1053 + Updated Atmel SAM4E and SAM4S demos to include a lot of additional test
1055 + Fixed a corner case issue in Atmel SAM4L low power tickless
1056 implementation, and added button interrupt handling.
1057 + Make the interrupt queue tests more tolerant to heave CPU loads.
1058 + Updated MSVC FreeRTOS simulator demo to include the latest standard test
1060 + Updated MingW/Eclipse FreeRTOS simulator demo to match the FreeRTOS MSVC
1062 + Updated all demos that use FreeRTOS+Trace to work with the latest trace
1066 Changes between V8.1.1 and V8.1.2 released September 2nd 2014
1068 Move the defaulting of configUSE_PORT_OPTIMISED_TASK_SELECTION into the
1069 individual port layers where necessary so it does not affect ports that do
1070 not support the definition.
1072 Changes between V8.1.0 and V8.1.1 released August 29th 2014
1074 By popular requests - a minor patch to V8.1.0 to re-instate the ability to
1075 give a mutex type semaphore (with priority inheritance) from an interrupt
1078 Changes between V8.0.1 and V8.1.0 released August 26th 2014
1080 FreeRTOS scheduler, kernel, demo and test updates:
1082 + Improved the priority inheritance algorithms to assist integration with
1083 off the shelf middleware that may hold multiple mutexes simultaneously.
1084 + Introduce heap_5.c, which is similar to heap_4.c but allows the heap to
1085 span multiple non-contiguous memory regions.
1086 + Updated all Cortex-A9 ports to help trap a couple of common usage errors -
1087 the first being when a task incorrectly attempts to exit its implementing
1088 function and the second being when a non interrupt safe API function is
1089 called from an interrupt.
1090 + Update all Cortex-A9 ports to remove obsolete mode switches prior to
1091 restoring a task context.
1092 + configUSE_PORT_OPTIMISED_TASK_SELECTION now defaults to 1 instead of 0.
1093 + Update all Cortex-M3/4F ports to trap a non interrupt safe API function
1094 being called from an interrupt handler.
1095 + Simplify the alignment checks in heap_4.c.
1096 + Update the MSVC Windows simulator demo to use heap_5.c in place of
1097 heap_4.c to ensure end users have an example to refer to.
1098 + Updated standard demo test code to test the new priority inheritance
1100 + Updated the standard demo tasks to make use of stdint and the FreeRTOS
1101 specific typedefs that were introduced in FreeRTOS V8.0.0.
1102 + Introduce the pdMS_TO_TICKS() macro as a more user friendly and intuitive
1103 alternative to pdTICKS_PER_MS - both of which can be used to convert a
1104 time specified in milliseconds to a time specified in RTOS ticks.
1105 + Fix a bug in the Tasking compiler's Cortex-M port that resulted in an
1106 incorrect value being written to the basepri register. This only effects
1107 users of the Tasking compiler.
1108 + Update the Zynq demo to use version 2014.2 of the SDK and add in an lwIP
1109 example that demonstrates lwIP being used with both its raw and sockets
1111 + Updated the CCS Cortex-R4 port to enable it to be built with the latest
1114 New ports and demo applications:
1116 + Two Renesas RX64M ports (RXv2 core) and demos introduced, one for the GCC
1117 compiler and one for the Renesas compiler. Both demos use e2 studio.
1118 + Generic IAR Cortex-A5 port (without any reliance on a GIC) introduced.
1119 The new port is demonstrated on an Atmel SAMA5D3 XPlained board.
1121 FreeRTOS+ component updates:
1123 + Update CyaSSL to the latest version.
1124 + Updated the FreeRTOS+ components supplied directly by Real Time Engineers
1125 Ltd. to make use of stdint and the FreeRTOS specific typedefs that were
1126 introduced in FreeRTOS V8.0.0.
1127 + Rework and simplify the FreeRTOS+FAT SL RAM disk driver.
1129 Miscellaneous updates and maintenance:
1131 + Update the IAR and DS-5/ARM RZ demos to target the official RZ RSK
1132 hardware in place of the previously targeted Renesas internal (not
1133 publicly available) hardware.
1134 + Various other maintenance tasks.
1137 Changes between V8.0.0 and V8.0.1 released 2nd May 2014
1139 + Minor fixes to the event group functionality that was released in V8.0.0.
1140 The 'clear bits from ISR' functionality is now implemented using a
1141 deferred interrupt callback instead of a function, and the 'wait bits' and
1142 'task sync' functions now correctly clear internal control bits before
1143 returning a value in every possible path through the respective functions.
1144 + Ensure the updating of internal control data is protected by a critical
1145 section after a task is deleted or suspended.
1146 + Minor fixes to FreeRTOS+FAT SL - namely seeking beyond the end of a file
1147 when the offset was not a multiple of the sector size.
1148 + Ensure Cortex-A9 system registers are only ever accessed as 32-bit values,
1149 even when only the lest significant byte of the register is implemented.
1153 + Updated the XMC4200 IAR project so it links with version 7.x of the IAR
1156 + Add pcTimerGetName() API function.
1157 + Call _reclaim_reent() when a task is deleted if configUSE_NEWLIB_REENTRANT
1160 Changes between V7.6.0 and V8.0.0 released 19th Feb 2014
1162 https://www.FreeRTOS.org/upgrading-to-FreeRTOS-V8.html
1164 FreeRTOS V8.x.x is a drop-in compatible replacement for FreeRTOS V7.x.x,
1165 although a change to the type used to reference character strings may result
1166 in application code generating a few (easily clearable) compiler warnings
1167 after the upgrade, and an updated typedef naming convention means use of the
1168 old typedef names is now discouraged.
1169 See https://www.FreeRTOS.org/upgrading-to-FreeRTOS-V8.html for full
1172 New features and functionality:
1174 + Event groups - see https://www.FreeRTOS.org/FreeRTOS-Event-Groups.html
1175 + Centralised deferred interrupt processing - see
1176 https://www.FreeRTOS.org/xTimerPendFunctionCallFromISR.html
1180 + Previously, when a task left the Blocked state, a context switch was
1181 performed if the priority of the unblocked task was greater than or equal
1182 to the priority of the Running task. Now a context switch is only
1183 performed if the priority of the unblocked task is greater than the
1184 priority of the Running task.
1185 + New low power tickless demonstration project that targets the ST STM32L
1186 microcontroller - see
1187 https://www.FreeRTOS.org/STM32L-discovery-low-power-tickless-RTOS-demo.html
1188 + Add xPortGetMinimumEverFreeHeapSize() to heap_4.c.
1189 + Small change to the tickless low power implementation on the SAM4L to
1190 ensure the alarm value (compare match value) cannot be set to zero when a
1191 tickless period is exited due to an interrupt originating from a source
1192 other than the RTOS tick.
1193 + Update the GCC/Eclipse Win32 simulator demo to make better use of Eclipse
1194 resource filters and match the functionality of the MSVC equivalent.
1195 + xTaskIsTaskSuspended() is no longer a public function. Use
1196 eTaskGetState() in its place.
1197 + Improved trace macros, including tracing of heap usage.
1198 + Remove one level of indirection when accepting interrupts on the PIC32MZ.
1199 + Add Cortex-A9 GCC port layer.
1200 + Add Xilinx Zynq demo application.
1203 Changes between V7.5.3 and V7.6.0 released 18th November 2013
1205 V7.6.0 changes some behaviour when the co-operative scheduler is used (when
1206 configUSE_PREEMPTION is set to 0). It is important to note that the
1207 behaviour of the pre-emptive scheduler is unchanged - the following
1208 description only applies when configUSE_PREEMPTION is set to 0:
1210 WHEN configUSE_PREEMPTION IS SET TO 0 (which is in a small minority of
1211 cases) a context switch will now only occur when a task places itself into
1212 the Blocked state, or explicitly calls taskYIELD(). This differs from
1213 previous versions, where a context switch would also occur when implicitly
1214 moving a higher priority task out of the Blocked state. For example,
1215 previously, WHEN PREEMPTION WAS TURNED OFF, if task A unblocks task B by
1216 writing to a queue, then the scheduler would switch to the higher priority
1217 task. Now, WHEN PREEMPTION IS TURNED OFF, if task A unblocks task B by
1218 writing to a queue, task B will not start running until task A enters the
1219 Blocked state or task A calls taskYIELD(). [If configUSE_PREEMPTION is not
1220 set to 0, so the normal pre-emptive scheduler is being used, then task B
1221 will start running immediately that it is moved out of the Blocked state].
1225 + Added a port layer and a demo project for the new PIC32MZ architecture.
1226 + Update the PIC32MX port layer to re-introduce some ehb instructions that
1227 were previously removed, add the ability to catch interrupt stack
1228 overflows (previously only task stack overflows were trapped), and also
1229 add the ability to catch an application task incorrectly attempting to
1230 return from its implementing function.
1231 + Make dramatic improvements to the performance of the Win32 simulator port
1233 + Ensure tasks that are blocked indefinitely report their state as Blocked
1234 instead of Suspended.
1235 + Slight improvement to the Cortex-M4F port layers where previously one
1236 register was inadvertently being saved twice.
1237 + Introduce the xSemaphoreCreateBinary() API function to ensure consistency
1238 in the semantics of how each semaphore type is created. It is no longer
1239 recommended to use vSemaphoreCreateBinary() (the version prefixed with a
1240 'v'), although it will remain in the code for backward compatibility.
1241 + Update the Cortex-M0 port layers to allow the scheduler to be started
1242 without using the SVC handler.
1243 + Added a build configuration to the PIC32MX MPLAB X demo project that
1244 targets the PIC32 USB II starter kit. Previously all the build
1245 configurations required the Explorer 16 hardware.
1246 + Some of the standard demo tasks have been updated to ensure they execute
1247 correctly with the updated co-operative scheduling behaviour.
1248 + Added comprehensive demo for the Atmel SAM4E, including use of
1249 FreeRTOS+UDP, FreeRTOS+FAT SL and FreeRTOS+CLI.
1253 + Minor maintenance on FreeRTOS+UDP.
1255 Changes between V7.5.2 and V7.5.3 released October 14 2013
1259 + Prior to V7.5.x yields requested from the tick hook would occur in the
1260 same tick interrupt - revert to that original behaviour.
1261 + New API function uxQueueSpacesAvailable().
1262 + Introduced the prvTaskExitError() function to Cortex-M0, Cortex-M3/4
1263 and Cortex-M4F ports. prvTaskExitError() is used to trap tasks that
1264 attempt to return from their implementing functions (tasks should call
1265 vTaskDelete( NULL ); if they want to exit).
1266 + The Cortex-M0 version of portSET_INTERRUPT_MASK_FROM_ISR and
1267 portCLEAR_INTERRUPT_MASK_FROM_ISR are now fully nestable.
1268 + Improved behaviour and robustness of the default Cortex-M tickless idle
1270 + Add workaround for silicon errata PMU_CM001 in Infineon XMC4000 devices to
1271 all Cortex-M4F ports.
1272 + Add Cortex-M0 port for Keil.
1273 + Updated Cortus port.
1274 + Ensure _impure_ptr is initialised before the scheduler is started.
1275 Previously it was not set until the first context switch.
1279 + Update FreeRTOS+UDP to V1.0.1 - including direct integration of the
1280 FreeRTOS+Nabto task, improvements to the DHCP behaviour, and a correction
1281 to the test that prevents the network event hook being called on the first
1282 network down event. The FreeRTOS+UDP change history is maintained
1284 + Correct the __NVIC_PRIO_BITS setting in the LPC18xx.h header files
1285 provided in the NXP CMSIS library, then update the interrupts used by the
1286 LPC18xx demos accordingly.
1287 + Replace double quotes (") with single quotes (') in FreeRTOS+CLI help
1288 strings to ensure the strings can be used with the JSON descriptions used
1289 in the FreeRTOS+Nabto demos.
1291 Demo and miscellaneous changes:
1293 + Added demo for the Atmel SAMD20 Cortex-M0+. The demo includes
1295 + Added a demo for the Infineon Cortex-M0 that can be built with the IAR
1297 + Updated the Infineon XMC4000 demos for IAR, Keil, GCC and Tasking tools,
1298 with additional build configurations to directly support the XMC4200 and
1299 XMC4400 devices, in addition to the previously supported XMC4500.
1300 + Updated the demo application.
1301 + Added additional trace macros traceMALLOC and traceFREE to track heap
1304 Changes between V7.5.0 and V7.5.2 released July 24 2013
1306 V7.5.2 makes the new Cortex-M vPortCheckInterruptPriority() function
1307 compatible with the STM32 standard peripheral driver library, and adds
1308 an extra critical section to the default low power tickless mode
1309 implementation. Only users of the STM32 peripheral library or the default
1310 tickless implementation need update from version 7.5.0.
1312 Changes between V7.4.2 and V7.5.0 released July 19 2013
1314 V7.5.0 is a major upgrade that includes multiple scheduling and efficiency
1315 improvements, and some new API functions.
1317 Compatibility information for FreeRTOS users:
1318 FreeRTOS V7.5.0 is backward compatible with FreeRTOS V7.4.0 with one
1319 exception; the vTaskList() and vTaskGetRunTimeStats() functions are now
1320 considered legacy, having been replaced by the single uxTaskGetSystemState()
1321 function. configUSE_STATS_FORMATTING_FUNCTIONS must be set to 1 in
1322 FreeRTOSConfig.h for vTaskList() and vTaskGetRunTimeStats() to be
1325 Compatibility information for FreeRTOS port writers:
1326 vTaskIncrementTick() is now called xTaskIncrementTick() (because it now
1331 + Multiple scheduling and efficiency improvements.
1332 + Core kernel files now pass PC-Lint V8 static checking without outputting
1333 any warnings (information on the test conditions will follow).
1337 + uxTaskGetSystemState() https://www.FreeRTOS.org/uxTaskGetSystemState.html
1338 + xQueueOverwrite() https://www.FreeRTOS.org/xQueueOverwrite.html
1339 + xQueueOverwriteFromISR()
1340 + xQueuePeekFromISR()
1342 The following ports and demos, which were previously available separately,
1343 are now incorporated into the main FreeRTOS zip file download:
1346 + ARM Cortex-A9 ARM compiler
1348 + Microsemi SmartFusion2
1350 New FreeRTOSConfig.h settings
1351 https://freertos.org/a00110.html
1353 + configUSE_TIME_SLICING
1354 + configUSE_NEWLIB_REENTRANT
1355 + configUSE_STATS_FORMATTING_FUNCTIONS
1356 + configINCLUDE_APPLICATION_DEFINED_PRIVILEGED_FUNCTIONS
1360 + (MPU port only) The configINCLUDE_APPLICATION_DEFINED_PRIVILEGED_FUNCTIONS
1361 options provides a mechanism that allows application writers to execute
1362 certain functions in privileged mode even when a task is running in user
1364 + Ports that support interrupt nesting now include a configASSERT() that
1365 will trigger if an interrupt safe FreeRTOS function is called from an
1366 interrupt that has a priority designated as above the maximum system/API
1367 call interrupt priority.
1368 + The included FreeRTOS+Trace recorder code has been updated to the latest
1369 version, and the demo applications that use the trace recorder code have
1370 been updated accordingly.
1371 + The FreeRTOS Windows Simulator (MSVC version only) has been updated to
1372 include a new basic 'blinky' build option in addition to the original
1373 comprehensive build option.
1374 + Improve RAM usage efficiency of heap_4.c and heap_2.c.
1375 + Prevent heap_4.c from attempting to free memory blocks that were not
1376 allocated by heap_4.c, or have already been freed.
1377 + As FreeRTOS now comes with FreeRTOS+FAT SL (donated by HCC) the Chan FATfs
1378 files have been removed from FreeRTOS/Demo/Common.
1379 + Fix build error when R4 port is build in co-operative mode.
1380 + Multiple port and demo application maintenance activities.
1382 Changes between V7.4.1 and V7.4.2 released May 1 2013
1384 NOTE: There are no changes in the FreeRTOS kernel between V7.4.1 and V7.4.2
1386 + Added FreeRTOS+FAT SL source code and demo project. The demo project
1387 runs in the FreeRTOS Windows simulator for easy and hardware independent
1388 experimentation and evaluation. See https://www.FreeRTOS.org/fat_sl
1390 Changes between V7.4.0 and V7.4.1 released April 18 2013
1392 + To ensure strict conformance with the spec and ensure compatibility with
1393 future chips data and instruction barrier instructions have been added to
1394 the yield macros of Cortex-M and Cortex-R port layers. For efficiency
1395 the Cortex-M port layer "yield" and "yield" from ISR are now implemented
1396 separately as the barrier instructions are not required in the ISR case.
1397 + Added FreeRTOS+UDP into main download.
1398 + Reorganised the FreeRTOS+ directory so it now matches the FreeRTOS
1399 directory with Source and Demo subdirectories.
1400 + Implemented the Berkeley sockets select() function in FreeRTOS+UDP.
1401 + Changed (unsigned) casting in calls to standard library functions with
1403 + Added the Atmel SAM4L and Renesas RX100 demos that demonstrates the
1404 tickless (tick suppression) low power FreeRTOS features.
1405 + Add a new RL78 IAR demo that targets numerous new RL78 chips and
1407 + Adjusted stack alignment on RX200 ports to ensure an assert was not
1408 falsely triggered when configASSERT() is defined.
1409 + Updated the Cortex_M4F_Infineon_XMC4500_IAR demo to build with the latest
1411 + Corrected header comments in the het.c and het.h files (RM48/TMS570 demo).
1414 Changes between V7.3.0 and V7.4.0 released February 20 2013
1416 + New feature: Queue sets. See:
1417 https://www.FreeRTOS.org/Pend-on-multiple-rtos-objects.html
1418 + Overhauled the default tickless idle mode implementation provided with the
1419 ARM Cortex-M3 port layers.
1420 + Enhanced tickless support in the core kernel code with the introduction of
1421 the configEXPECTED_IDLE_TIME_BEFORE_SLEEP macro and the
1422 eTaskConfirmSleepModeStatus() function.
1423 + Added the QueueSet.c common demo/test file. Several demo applications
1424 have been updated to use the new demo/test tasks.
1425 + Removed reliance on the PLIB libraries from the MPLAB PIC32 port layer and
1427 + Added the FreeRTOS+Trace recorder code to the MSVC Win32 demo.
1428 + Renamed eTaskStateGet() to eTaskGetState() for consistency, and added a
1429 pre-processor macro for backward compatibility with the previous name.
1430 + Updated functions implemented in the core queue.c source file to allow
1431 queue.h to be included from the .c file directly (this prevents compiler
1432 warnings that were generated by some compilers).
1433 + Updated the CCS Cortex-R4 port layer to replace the CLZ assembler function
1434 with the CLZ compiler intrinsic that is provided by the latest versions of
1435 the CCS ARM compiler.
1436 + Updated all heap_x.c implementations to replace the structure that was
1437 used to ensure the start of the heap was aligned with a more portable
1438 direct C code implementation.
1439 + Added support for PIC24 devices that include EDS.
1440 + Minor optimisations to the PIC32 port layer.
1441 + Minor changes to tasks.c that allow the state viewer plug-ins to display
1442 additional information.
1443 + Bug fix: Update prvProcessReceivedCommands() in timers.c to remove an
1444 issue that could occur if the priority of the timer daemon task was set
1445 below the priority of tasks that used timer services.
1446 + Update the FreeRTOS+Trace recorder code to the latest version.
1448 Changes between V7.2.0 and V7.3.0 released October 31 2012
1450 + Added ability to override the default scheduler task selection mechanism
1451 with implementations that make use of architecture specific instructions.
1452 + Added ability to suppress tick interrupts during idle time, and in so
1453 doing, provide the ability to make use of architecture specific low power
1455 + Added the portSUPPRESS_TICKS_AND_SLEEP() macro and vTaskStepTick() helper
1457 + Added the configSYSTICK_CLOCK_HZ configuration constant.
1458 + Reworked the Cortex-M3 and Cortex-M4F port layers for GCC, Keil and IAR to
1459 directly support basic power saving functionality.
1460 + Added hooks to allow basic power saving to be augmented in the application
1461 by making use of chip specific functionality.
1462 + Minor change to allow mutex type semaphores to be used from interrupts
1463 (which would not be a normal usage model for a mutex).
1464 + Change the behaviour of the interrupt safe interrupt mask save and restore
1465 macros in the Cortex-M ports. The save macro now returns the previous
1466 mask value. The restore macro now uses the previous mask value. These
1467 changes are not necessary for the kernel's own implementation, and are
1468 made purely because the macros were being used by application writers.
1469 + Added eTaskStateGet() API function.
1470 + Added port specific optimisations to the PIC32 port layer, and updated the
1471 PIC32 demo applications to make use of this new feature.
1472 + Added port specific optimisations to the Win32 simulator port.
1473 + Added new ports and demo applications for the TI Hercules RM48 and TMS570
1474 safety microcontrollers.
1475 + Added SAM3 demos targeting the ATSAM3S-EK2 and ATSAM3X-EK evaluation
1477 + Updated the PIC32 MPLAB X project to manually set the compiler include
1478 paths instead of using the IDE entry box following reports that the
1479 include paths were somehow being deleted.
1480 + Improved character handling in FreeRTOS+CLI.
1482 Changes between V7.1.1 and V7.2.0 released 14 August 2012
1484 FreeRTOS V7.2.0 is backward compatible with FreeRTOS V7.1.2.
1486 + Added a FreeRTOS+ sub-directory. The directory contains some FreeRTOS+
1487 source code, and example projects that use the FreeRTOS Win32 simulator.
1488 + Added a new example heap allocation implementation (heap_4.c) that
1489 includes memory block coalescence.
1490 + Added a demo that targets the Atmel SAM4S Cortex-M4 based microcontroller.
1491 The demo is preconfigured to build using the free Atmel Studio 6 IDE and
1493 + Added xSemaphoreTakeFromISR() implementation.
1494 + The last parameter in ISR safe FreeRTOS queue and semaphore functions
1495 (xHigherPriorityTaskWoken) is now optional and can be set to NULL if it
1497 + Update the IAR and MSP430X ports to clear all lower power mode bits before
1498 exiting the tick interrupt [bug fix].
1499 + Allow xQueueReset() to be used, even when the queues event lists are not
1501 + Added a vQueueDelete() handler for the FreeRTOS MPU port (this was
1502 previously missing).
1503 + Updated the vPortSVCHandler() functions in the FreeRTOS MPU port layer to
1504 ensure it compiles with the latest ARM GCC compilers from Linaro.
1505 + Updated the prvReadGP() function in the NIOS II port to ensure the compiler
1506 can choose any register for the functions parameter (required at high
1507 compiler optimisation levels).
1508 + Add #error macros into the Keil and IAR Cortex-M ports to ensure they
1509 cannot be built if the user has set configMAX_SYSCALL_INTERRUPT_PRIORITY
1511 + Added comments in the FreeRTOSConfig.h files associated with Cortex-M3 and
1512 Cortex-M4 demos stating that the configMAX_SYSCALL_INTERRUPT_PRIORITY
1513 parameter must not be set to 0.
1514 + Introduce new INCLUDE_xQueueGetMutexHolder configuration constant
1516 + Added two new list handling macros - for internal use only in upcoming new
1518 + Removed all mention of the legacy vTaskStartTrace and ulTaskEndTrace
1519 macros. FreeRTOS+Trace supersedes the legacy trace.
1520 + Added a configASSERT() into the vPortFree() function in heap_1.c as it is
1521 invalid for the function to be called.
1522 + Made the xRxLock and xTxLock members of the queue structure volatile.
1523 This is probably not necessary, and is included as a precautionary
1525 + Modify the assert() that checks to see if the priority passed into an
1526 xTaskCreate() function is within valid bounds to permit the assert to be
1527 used in the FreeRTOS MPU port.
1528 + The software timer service (daemon) task is now created in a way that
1529 to ensure compatibility with FreeRTOS MPU.
1531 Changes between V7.1.0 and V7.1.1 released May 1 2012
1535 The following ports are brand new:
1538 The following ports have been available as separate downloads for a number
1539 of months, but are now included in the main FreeRTOS download.
1542 + Cortex-M4F GCC (with full floating point support)
1547 The following demos are brand new:
1548 + Renesas RX63N RDK (Renesas compiler)
1550 The following demos have been available as separate downloads for a number
1551 of months, but are now included in the main FreeRTOS download.
1552 + NXP LPC1114 GCC/LPCXpresso
1554 + Infineon XMC4500 GCC/Atollic
1555 + Infineon XMC4500 IAR
1556 + Infineon XMC4500 Keil
1557 + Infineon XMC4500 Tasking
1560 Kernel miscellaneous / maintenance:
1562 + Introduced the portSETUP_TCB() macro to remove the requirement for the
1563 Windows simulator to use the traceTASK_CREATE() macro, leaving the trace
1564 macro available for use by FreeRTOS+Trace (https://www.FreeRTOS.org/trace).
1565 + Added a new trace macro, traceMOVE_TASK_TO_READY_STATE(), to allow future
1566 FreeRTOS+Trace versions to provide even more information to users.
1567 + Updated the FreeRTOS MPU port to be correct for changes that were
1568 introduced in FreeRTOS V7.1.0.
1569 + Introduced the xQueueReset() API function.
1570 + Introduced the xSemaphoreGetMutexHolder() API function.
1571 + Tidy up various port implementations to add the static key word where
1572 appropriate, and remove obsolete code.
1573 + Slight change to the initial stack frame given to the RX600 ports to allow
1574 them to be used in the Eclipse based E2Studio IDE without confusing GDB.
1575 + Correct the alignment given to the initial stack of Cortex-M4F tasks.
1576 + Added a NOP following each DINT instruction on MSP430 devices for strict
1577 conformance with the instructions on using DINT.
1578 + Changed the implementation of thread deletes in the Win32 port to prevent
1579 the port making use of the traceTASK_DELETE() trace macros - leaving this
1580 macro free for use by FreeRTOS+Trace.
1581 + Made some benign changes to the RX600 Renesas compiler port layer to
1582 ensure the code can be built to a library without essential code being
1583 removed by the linker.
1584 + Reverted the change in the name of the uxTaskNumber variable made in
1585 V7.1.0 as it broke the IAR plug-in.
1588 Demo miscellaneous / maintenance:
1590 + The command interpreter has now been formally released as FreeRTOS+CLI,
1591 and been moved out of the main FreeRTOS download, to instead be available
1592 from the FreeRTOS+ Ecosystem site https://www.FreeRTOS.org/plus.
1593 + flash_timer.c/h has been added to the list of standard demo tasks. This
1594 performs the same functionality as the flash.c tasks, but using software
1595 timers in place of tasks.
1596 + Upgraded the PIC32 demo as follows: Changes to how the library functions
1597 are called necessitated by the new compiler version, addition of MPLAB X
1598 project with PIC32MX360, PIC32MX460 and PIC32MX795 configurations,
1599 addition of simply blinky demo, updated FreeRTOSConfig.h to include more
1600 parameters, addition of hook function stubs.
1601 + The MSP430X IAR and CCS demos have been updated to ensure the power
1602 settings are correct for the configured CPU frequency.
1603 + Rowley CrossWorks projects have been updated to correct the "multiple
1604 definition of ..." warnings introduced when the toolchain was updated.
1605 + Updated various FreeRTOSConfig.h header files associated with projects
1606 that build with Eclipse to include a #error statement informing the user
1607 that the CreateProjectDirectoryStructure.bat batch file needs to be
1608 executed before the projects can be opened.
1609 + Renamed directories that included "CCS4" in their name to remove the '4'
1610 and instead just be "CCS". This is because the demo was updated and
1611 tested to also work with later Code Composer Studio versions.
1612 + Updated the TCP/IP periodic timer frequency in numerous uIP demos to be
1613 50ms instead of 500ms.
1615 Changes between V7.0.2 and V7.1.0 released December 13 2011
1619 + Cortex-M4F IAR port.
1620 + Cortex-M4F Keil/RVDS port.
1625 + NXP LPC4350 using the Keil MDK, and demonstrated on a Hitex development
1627 + ST STM32F407 using the IAR Embedded Workbench for ARM, and demonstrated on
1628 the IAR STM32F407ZG-SK starter kit.
1629 + Infineon TriCore TC1782, using the GCC compiler, demonstrated on the
1630 TriBoard TC1782 evaluation board.
1631 + Renesas RX630, using the Renesas compiler and HEW, demonstrated on an
1632 RX630 RSK (Renesas Starter Kit).
1634 Miscellaneous / maintenance:
1636 + Removed all calls to printf() from the K60/IAR Kinetis demo so the project
1637 can execute stand alone - without being connected to the debugger.
1638 + Completed the command interpreter framework. Command handlers now receive
1639 the entire command string, giving them direct access to parameters.
1640 Utility functions are provided to check the number of parameters, and
1641 return parameter sub-strings.
1642 + The previously documented fix for the bug in xTaskResumeFromISR() that
1643 effected (only) ports supporting interrupt nesting has now been
1644 incorporated into the main release.
1645 + The portALIGNMENT_ASSERT_pxCurrentTCB() definition has been added to allow
1646 specific ports to skip the second stack alignment check when a task is
1647 created. This is because the second check is not appropriate for some
1648 ports - including the new TriCore port where the checked pointer does not
1649 actually point to a stack.
1650 + The portCLEAN_UP_TCB() macro has been added to allow port specific clean
1651 up when a task is deleted - again this is required by the TriCore port.
1652 + Various other minor changes to ensure warning free builds on a growing
1653 number of microcontroller and toolchain platforms. This includes a
1654 (benign) correction to the prototype of the
1655 vApplicationStackOverflowHook() definition found in lots of recent demos.
1659 + The legacy trace mechanism has been completely removed - it has been
1660 obsolete for the years since the trace macros were introduced. The
1661 configuration constant configUSE_TRACE_FACILITY is now used to optionally
1662 include additional queue and task information. The additional information
1663 is intended to make the trace mechanism more generic, and allow the trace
1664 output to provide more information. When configUSE_TRACE_FACILITY is set
1666 - the queue structure includes an additional member to hold the queue
1667 type, which can be base, mutex, counting semaphore, binary semaphore
1669 - the queue structure includes an additional member to hold a queue
1670 number. A trace tool can set and query the queue number for its own
1671 purposes. The kernel does not use the queue number itself.
1672 - the TCB structure includes an additional member to hold a task number
1673 number. A trace tool can set and query the task number for its own
1674 purposes. The kernel does not use the task number itself.
1675 + Queues and all types of semaphores are now automatically allocated their
1676 type as they are created.
1677 + Added two new trace macros - traceTASK_PRIORITY_INHERIT() and
1678 traskTASK_PRIORITY_DISINHERIT().
1679 + Updated the traceQUEUE_CREATE_FAILED() macro to take a parameter that
1680 indicates the type of queue, mutex, or semaphore that failed to be
1682 + The position from which traceCREATE_MUTEX() is called has been moved from
1683 after the call to xQueueGenericSend() [within the same function] to before
1684 the call. This ensures the trace events occur in the correct order.
1685 + The value passed into tracePRIORITY_SET() has been corrected for the case
1686 where vTaskPrioritySet() is called with a null parameter.
1688 Changes between V7.0.1 and V7.0.2 released September 20 2011
1692 + The official FreeRTOS Renesas RX200 port and demo application have been
1693 incorporated into the main FreeRTOS zip file download.
1694 + The official FreeRTOS Renesas RL78 port and demo application have been
1695 incorporated into the main FreeRTOS zip file download.
1696 + The official FreeRTOS Freescale Kinetis K60 tower demo application has
1697 been incorporated into the main FreeRTOS zip file download. This includes
1698 an embedded web server example.
1699 + A new Microblaze V8 port layer has been created to replace the older, now
1700 deprecated, port layer. The V8 port supports V8.x of the Microblaze IP,
1701 including exceptions, caches, and the floating point unit. A new
1702 Microblaze demo has also been added to demonstrate the new Microblaze V8
1703 port layer. The demo application was created using V13.1 of the Xilinx
1704 EDK, and includes a basic embedded web server that uses lwIP V1.4.0.
1705 + The official FreeRTOS Fujitsu FM3 MB9A310 demo application has been
1706 incorporated into the main FreeRTOS zip file download. Projects are
1707 provided for both the IAR and Keil toolchains.
1712 + xTaskGetIdleTaskHandle() has been added.
1713 + xTaskGetTimerDaemonTaskHandle() has been added.
1714 + pcTaskGetTaskName() has been added.
1715 + vSemaphoreDelete() macro has been added to make it obvious how to delete
1716 a semaphore. In previous versions vQueueDelete() had to be used.
1717 + vTaskCleanUpResources() has been removed. It has been obsolete for a
1719 + portPOINTER_SIZE_TYPE has been introduced to prevent compiler warnings
1720 being generated when the size of a pointer does not match the size of
1721 the stack type. This will (has already) be used in new ports, but will
1722 not be retrofitted to existing ports until the existing port itself is
1725 Other updates and news:
1727 + The core files have all been modified to tighten the coding standard even
1728 further. These are style, not functional changes.
1729 + All ARM7 port layers have been slightly modified to prevent erroneous
1730 assert() failures when tasks are created and configASSERT() is defined.
1731 + All ARM IAR projects have been updated to build with the latest V6.2.x
1732 versions of the IAR Embedded Workbench for ARM tools (EWARM). This was
1733 necessary due to a change in the way EWARM uses the CMSIS libraries.
1734 + The PIC32 port layer has been updated in preparation for V2 of the C32
1736 + The old Virtex-4 Microblaze demo has been marked as deprecated. Please
1737 use the brand new Spartan-6 port and demo in its place.
1738 + The bones of a new generic command interpreter is located in
1739 FreeRTOS/Demo/Common/Utils/CommandInterpreter.c. This is still a work in
1740 progress, and not documented. It is however already in use. It will be
1741 documented in full when the projects that are already using it are
1743 + A couple of new standard demos have been included. First, a version of
1744 flop.c called sp_flop.c. This is similar to flop.c, but uses single
1745 precision floats in place of double precision doubles. This allows the
1746 for testing ports to processors that have only single precision floating
1747 point units, and revert to using emulated calculations whenever a double
1748 is used. Second, comtest_strings.c has been included to allow the test
1749 of UART drivers when an entire string is transmitted at once. The
1750 previous comtest.c only used single character transmission and reception.
1751 + lwIP V1.4.0 is now included in the FreeRTOS/Demo/Common directory, and
1752 used by a couple of new demos.
1754 Changes between V7.0.0 and V7.0.1 released May 13 2011
1756 + Added a Fujitsu FM3 demo application for both the IAR and Keil tool
1758 + Added a SmartFusion demo application for all of the IAR, Keil and
1759 SoftConsole (GCC/Eclipse) tool chains.
1760 + Updated the RX600 port and demo applications to take into account the
1761 different semantics required when using the latest (V1.0.2.0) version of
1762 the Renesas compiler.
1763 + Modified the RX600 Ethernet driver slightly to make it more robust under
1764 heavy load, and updated the uIP handling task to make use of the FreeRTOS
1766 + Slightly changed the PIC32 port layer to move an ehb instruction in line
1767 with the recommendations of the MIPS core manual, and ensure 8 byte stack
1768 alignment is truly always obtained.
1769 + Changed the behaviour when tasks are suspended before the scheduler has
1770 been started. Before, there needed to be at least one task that was not
1771 in the suspended state. This is no longer the case.
1773 Changes between V6.1.1 and V7.0.0 released April 8 2011
1775 FreeRTOS V7.0.0 is backward compatible with FreeRTOS V6.x.x
1779 + Introduced a new software timer implementation.
1780 + Introduced a new common demo application file to exercise the new timer
1782 + Updated the Win32/MSVC simulator project to include the new software timer
1783 demo tasks and software timer tick hook test. Much simpler software timer
1784 demonstrations are included in the demo projects for both of the new ports
1785 (MSP430X with CCS4 and STM32 with TrueStudio).
1786 + Various enhancements to the kernel implementation in tasks.c. These are
1787 transparent to users and do not effect the pre-existing API.
1788 + Added calls to configASSERT() within the kernel code. configASSERT() is
1789 functionally equivalent to the standard C assert() macro, but does not
1790 rely on the compiler providing assert.h.
1794 + Updated the MSP430X IAR port and demo project to include support for the
1795 medium memory model.
1796 + Added a demo project for the MSP430X that targets the MSP430X Discovery
1797 board and uses the Code Composer Studio 4 tools. This demo includes use
1798 of the new software timer implementation.
1799 + Added an STM32F100RB demo project that targets the STM32 Discovery Board
1800 and uses the TrueStudio Eclipse based IDE from Atollic.
1801 + Removed some compiler warnings from the PSoC demo application.
1802 + Updated the PIC32 port layer to ensure the
1803 configMAX_SYSCALL_INTERRUPT_PRIORITY constant works as expected no matter
1804 what its value is (within the valid range set by the microcontroller
1806 + Updated the PIC24, dsPIC and PIC32 projects so they work with the latest
1807 MPLAB compiler versions from Microchip.
1808 + Various cosmetic changes to prepare for a standards compliance statement
1809 that will be published after the software release.
1812 Changes between V6.1.0 and V6.1.1 released January 14 2011
1814 + Added two new Windows simulator ports. One uses the free Microsoft Visual
1815 Studio 2010 express edition, and the other the free MingW/Eclipse
1816 environment. Demo projects are provided for both.
1817 + Added three demo projects for the PSoC 5 (CYAC5588). These are for the
1818 GCC, Keil, and RVDS build tools, and all use the PSoC Creator IDE.
1819 + Added a demo for the low power STM32L152 microcontroller using the IAR
1821 + Added a new port for the MSP430X core using the IAR Embedded Workbench.
1822 + Updated all the RX62N demo projects that target the Renesas Demonstration
1823 Kit (RDK) to take into account the revered LED wiring on later hardware
1824 revisions, and the new J-Link debug interface DLL.
1825 + Updated all the RX62N demo projects so the IO page served by the example
1826 embedded web server works with all web browsers.
1827 + Updated the Red Suite projects to work with the up coming Red Suite
1828 release, and to use a more recent version of the CMSIS libraries.
1829 + Added the traceTAKE_MUTEX_RECURSIVE_FAILED() trace macro.
1830 + Removed the (pointless) parameter from the traceTASK_CREATE_FAILED()
1832 + Introduced the portALT_GET_RUN_TIME_COUNTER_VALUE() macro to compliment
1833 the already existing portGET_RUN_TIME_COUNTER_VALUE(). This allows for
1834 more flexibility in how the time base for the run time statistics feature
1836 + Added a "cpsie i" instruction before the "svc 0" instruction used to start
1837 the scheduler in each of the Cortex M3 ports. This is to ensure that
1838 interrupts are globally enabled prior to the "svc 0" instruction being
1839 executed in cases where interrupts are left disabled by the C start up
1841 + Slight optimisation in the run time stats calculation.
1843 Changes between V6.0.5 and V6.1.0 released October 6 2010
1845 + Added xTaskGetTickCountFromISR() function.
1846 + Modified vTaskSuspend() to allow tasks that have just been created to be
1847 immediately suspended even when the kernel has not been started. This
1848 allows them to effectively start in the Suspended state - a feature that
1849 has been asked for on numerous occasions to assist with initialisation
1851 + Added ports for the Renesas RX62N using IAR, GCC and Renesas tool suites.
1852 + Added a STM32F103 demo application that uses the Rowley tools.
1853 + Under specific conditions xFreeBytesRemaining within heap_2.c could end up
1854 with an incorrect value. This has been fixed.
1855 + xTaskCreateGeneric() has a parameter that can be used to pass the handle
1856 of the task just created out to the calling task. The assignment to this
1857 parameter has been moved to ensure it is assigned prior to the newly
1858 created having any possibility of executing. This takes into account the
1859 case where the assignment is made to a global variable that is accessed by
1860 the newly created task.
1861 + Fixed some build time compiler warnings in various FreeTCPIP (based on
1863 + Fixed some build time compiler warnings in Demo/Common/Minimal/IntQueue.c.
1865 Changes between V6.0.4 and V6.0.5 released May 17 2010
1867 + Added port and demo application for the Cortus APS3 processor.
1869 Changes between V6.0.3 and V6.0.4 released March 14 2010
1871 + All the contributed files that were located in the Demo/Unsupported_Demos
1872 directory have been removed. These files are instead now available in the
1873 new Community Contributions section of the FreeRTOS website. See
1874 https://www.FreeRTOS.org/RTOS-contributed-ports.html
1875 + The project file located in the Demo/CORTEX_STM32F107_GCC_Rowley directory
1876 has been upgraded to use V2.x of the Rowley Crossworks STM32 support
1878 + An initial Energy Micro EFM32 demo has been included. This will be
1879 updated over the coming months to make better use of the low power modes
1882 Changes between V6.0.2 and V6.0.3 released February 26 2010
1884 + SuperH SH7216 (SH2A-FPU) port and demo application added.
1885 + Slight modification made to the default implementation of
1886 pvPortMallocAligned() and vPortFreeAligned() macros so by default they
1887 just call pvPortMalloc() and vPortFree(). The macros are only needed to
1888 be defined when a memory protection unit (MPU) is being used - and then
1889 only depending on other configuration settings.
1891 Changes between V6.0.1 and V6.0.2 released January 9th 2010
1893 + Changed all GCC ARM 7 ports to use 0 as the SWI instruction parameter.
1894 Previously the parameter was blank and therefore only an implicit 0 but
1895 newer GCC releases do not permit this.
1896 + Updated IAR SAM7S and SAM7X ports to work with IAR V5.40.
1897 + Changed the stack alignment requirement for PIC32 from 4 bytes to 8 bytes.
1898 + Updated prvListTaskWithinSingleList() is it works on processors where the
1899 stack grows up from low memory.
1900 + Corrected some comments.
1901 + Updated the startup file for the RVDS LPC21xx demo.
1903 Changes between V6.0.0 and V6.0.1 released November 15th 2009
1905 + Altered pxPortInitialiseStack() for all Cortex-M3 ports to ensure the
1906 stack pointer is where the compiler expects it to be when a task first
1909 The following minor changes only effect the Cortex-M3 MPU port:
1911 + portRESET_PRIVILEGE() assembly macro updated to include a clobber list.
1912 + Added prototypes for all the privileged function wrappers to ensure no
1913 compile time warnings are generated no matter what the warning level
1915 + Corrected the name of portSVC_prvRaisePrivilege to
1916 portSVC_RAISE_PRIVILEGE.
1917 + Added conditional compilation into xTaskGenericCreate() to prevent some
1918 compilers issuing warnings when portPRIVILEGE_BIT is defined as zero.
1921 Changes between V5.4.2 and V6.0.0 released October 16th 2009
1923 FreeRTOS V6 is backward compatible with FreeRTOS V5.x.
1927 + FreeRTOS V6 is the first version to include memory protection unit (MPU)
1928 support. Two ports now exist for the Cortex M3, the standard FreeRTOS
1929 which does not include MPU support, and FreeRTOS-MPU which does.
1930 + xTaskCreateRestricted() and vTaskAllocateMPURegions() API functions added
1931 in support of FreeRTOS-MPU.
1932 + Wording for the GPL exception has been (hopefully) clarified. Also the
1933 license.txt file included in the download has been fixed (the previous
1934 version contained some corruption).
1938 + New API function xPortGetFreeHeapSize() added to heap_1.c and heap_2.c.
1939 + ARM7 GCC demo interrupt service routines wrappers have been modified to
1940 call the C portion using an __asm statement. This prevents the function
1941 call being inlined at higher optimisation levels.
1942 + ARM7 ports now automatically set the THUMB bit if necessary when
1943 setting up the initial stack of a task - removing the need for
1944 THUMB_INTERWORK to be defined. This also allows THUMB mode and ARM mode
1945 tasks to be mixed more easily.
1946 + All ARM7/9 ports now have portBYTE_ALIGNMENT set to 8 by default.
1947 + Various demo application project files have been updated to be up to date
1948 with the latest IDE versions.
1949 + The linker scripts used with command line GCC demos have been updated to
1950 include an eh_frame section to allow their use with the latest Yagarto
1951 release. Likewise the demo makefiles have been updated to include
1952 command line options to reduce or eliminate the eh_frame section all
1954 + The definition of portBYTE_ALIGNMENT_MASK has been moved out of the
1955 various memory allocation files and into the common portable.h header
1957 + Removed unnecessary use of portLONG, portSHORT and portCHAR.
1958 + Added LM3Sxxxx demo for Rowley CrossWorks.
1959 + Posix simulator has been upgraded - see the corresponding WEB page on the
1963 Changes between V5.4.1 and V5.4.2 released August 9th 2009
1965 + Added a new port and demo app for the Altera Nios2 soft core.
1966 + Added LPC1768 demo for IAR.
1967 + Added a USB CDC demo to all LPC1768 demos (Code Red, CrossWorks and IAR).
1968 + Changed clock frequency of LPC1768 demos to 99MHz.
1970 Changes between V5.4.0 and V5.4.1 released July 25th 2009
1972 + New hook function added. vApplicationMallocFailedHook() is (optionally)
1973 called if pvPortMalloc() returns NULL.
1974 + Additional casting added to xTaskCheckForTimeOut(). This prevents
1975 problems that can arise should configUSE_16_BIT_TICKS be set to 1 on a
1976 32 bit architecture (which would probably be a mistake, anyway).
1977 + Corrected the parameter passed to NVIC_SetPriority() to set the MAC
1978 interrupt priority in both LPC1768 demos.
1979 + Decreased the default setting of configMINIMAL_STACK_SIZE in the PIC32
1980 demo application to ensure the heap space was not completely consumed
1981 before the scheduler was started.
1983 Changes between V5.3.1 and V5.4.0 released July 13th 2009
1985 + Added Virtex5 / PPC440 port and demos.
1986 + Replaced the LPC1766 Red Suite demo with an LPC1768 Red Suite demo. The
1987 original demo was configured to use engineering samples of the CPU. The
1988 new demo has an improved Ethernet driver.
1989 + Added LPC1768 Rowley demo with zero copy Ethernet driver.
1990 + Reworked byte alignment code to ensure 8 byte alignment works correctly.
1991 + Set configUSE_16_BIT_TICKS to 0 in the PPC405 demo projects.
1992 + Changed the initial stack setup for the PPC405 to ensure the small data
1993 area pointers are setup correctly.
1995 Changes between V5.3.0 and V5.3.1 released June 21st 2009
1997 + Added ColdFire V1 MCF51CN128 port and WEB server demo.
1998 + Added STM32 Connectivity Line STM32107 Cortex M3 WEB server demo.
1999 + Changed the Cortex M3 port.c asm statements to __asm so it can be
2000 compiled using Rowley CrossWorks V2 in its default configuration.
2001 + Updated the Posix/Linux simulator contributed port.
2003 Changes between V5.2.0 and V5.3.0 released June 1st 2009
2007 + Added new (optional) feature that gathers statistics on the amount of CPU
2008 time used by each task.
2009 + Added a new demo application for the Atmel AT91SAM3U Cortex-M3 based
2011 + Added a new demo application for the NXP LPC1766 Cortex-M3 based
2013 + Added a contributed port/demo that allows FreeRTOS to be 'simulated' in a
2017 + Updated the Stellaris uIP WEB server demos to include the new run time
2018 statistics gathering feature - and include a served WEB page that
2019 presents the information in a tabular format.
2020 + Added in the lwIP port layer for the Coldfire MCF52259.
2021 + Updated the CrossWorks LPC2368 WEB server to include an image in the
2023 + Changed some of the timing in the initialisation of the LPC2368 MAC to
2024 permit its use on all part revisions.
2025 + Minor modifications to the core uIP code to remove some compiler warnings.
2026 + Added xTaskGetApplicationTaskTag() function and updated the OpenWatcom
2027 demo to make use of the new function.
2028 + Added contributed demos for AVR32 AP7000, STM32 Primer 2 and STM32 using
2030 + Heap_1.c and Heap_2.c used to define structures for the purpose of data
2031 alignment. These have been converted to unions to save a few bytes of
2032 RAM that would otherwise be wasted.
2033 + Remove the call to strncpy() used to copy the task name into the TCB when
2034 the maximum task name is configured to be 1 byte long.
2036 Changes between V5.1.2 and V5.2.0 released March 14th 2009
2038 + Optimised the queue send and receive functions (also used by semaphores).
2039 + Replaced the standard critical sections used to protect BIOS calls in the
2040 PC port to instead use scheduler locks. This is because the BIOS calls
2041 always return with interrupts enabled.
2042 + Corrected unclosed comments in boot.s.
2044 Changes between V5.1.1 and V5.1.2 released February 9th 2009
2046 + Added NEC V850ES port and demo.
2047 + Added NEC 78K0R port and demo.
2048 + Added MCF52259 port and demo.
2049 + Added the AT91SAM9XE port and demo.
2050 + Updated the MCF52233 FEC driver to work around a silicon bug that
2051 prevents the part auto negotiating some network parameters.
2052 + Minor modifications to the MCF52233 makefile to permit it to be used
2054 + Updated the STM32 primer files to allow them to be built with the latest
2055 version of the RIDE tools.
2056 + Updated the threads.js Java script used for kernel aware debugging in
2057 the Rowley CrossWorks IDE.
2060 Changes between V5.1.0 and V5.1.1 released November 20, 2008
2062 + Added Coldfire MCF52233 WEB server demo using GCC and Eclipse.
2063 + Added IAR MSP430 port and demo.
2064 + Corrected several compiler time issues that had crept in as tool versions
2066 + Included FreeRTOS-uIP - a faster uIP. This is not yet complete.
2068 Changes between V5.0.4 and V5.1.0 released October 24, 2008
2070 + Added a new port and demo application for the ColdFire V2 core using the
2071 CodeWarrior development tools.
2072 + Replaced the ARM7 demo that used the old (and now no longer supported)
2073 Keil compiler with a new port that uses the new Keil/RVDS combo.
2074 + Stack overflow checking now works for stacks that grow up from low
2075 memory (PIC24 and dsPIC).
2076 + BUG FIX - set the PIC32 definition of portSTACK_GROWTH to the correct
2078 + MSP430 port layers have been updated to permit tasks to place the
2079 microcontroller into power down modes 1 to 3. The demo applications have
2080 likewise been updated to demonstrate the new feature.
2081 + Replaced the two separate MSP430/Rowley port layers with a single and more
2083 + Added more contributed ports, including ports for NEC and SAM9
2085 + Changed the linker script used in the LPC2368 Eclipse demo.
2087 Changes between V5.0.3 and V5.0.4 released September 22, 2008
2089 + Completely re-written port for ColdFire GCC.
2090 + Bug fix: All Cortex M3 ports have a minor change to the code that sets
2091 the pending interrupt.
2092 + Some header files require that FreeRTOS.h be included prior to their
2093 inclusion. #error message have been added to all such header file
2094 informing users to the cause of the compilation error should the headers
2095 not be included in the correct order.
2097 Changes between V5.0.2 and V5.0.3 released July 31, 2008
2099 Changes relating to the Cortex M3:
2101 + Added configMAX_SYSCALL_INTERRUPT_PRIORITY usage to all the Cortex M3
2102 ports and demos. See the port documentation pages on the FreeRTOS.org
2103 WEB site for full usage information.
2104 + Improved efficiency of Cortex M3 port even further.
2105 + Ensure the Cortex M3 port works no matter where the vector table is
2107 + Added the IntQTimer demo/test tasks to a demo project for each CM3 port
2108 (Keil, GCC and IAR) to test the new configMAX_SYSCALL_INTERRUPT_PRIORITY
2110 + Added the mainINCLUDE_WEB_SERVER definition to the LM3SXXXX IAR and Keil
2111 projects to allow the WEB server to be conditionally excluded from the
2112 build and therefore allow use of the KickStart (code size limited)
2117 + Moved the PIC24 and dsPIC versions of vPortYield() from the C file to
2118 an assembly file to allow use with all MPLAB compiler versions. This also
2119 allows the omit-frame-pointer optimisation to be turned off.
2121 Changes between V5.0.0 and V5.0.2 released May 30, 2008
2123 + Updated the PIC32 port to allow queue API calls to be used from
2124 interrupts above the kernel interrupt priority, and to allow full
2125 interrupt nesting. Task stack usages has also been reduced.
2126 + Added a new PowerPC port that demonstrates how the trace macros can be
2127 used to allow the use of a floating point co-processor. The
2128 traceTASK_SWITCHED_OUT() and traceTASK_SWITCHED_INT() macros are used to
2129 save and restore the floating point context respectively for those tasks
2130 that actually use floating point operations.
2131 + BUG FIX: The first PPC405 port contained a bug in that it did not leave
2132 adequate space above the stack for the backchain to be saved when a task
2133 started to execute for the first time.
2134 + Updated queue.c to add in the means to allow interrupt nesting and for
2135 queue API functions to be called from interrupts that have a priority
2136 above the kernel priority. This is only supported on PIC32 ports thus
2138 + Fixed the compiler warnings that were generated when the latest version
2140 + Remove all inline usage of 'inline' from the core kernel code.
2141 + Added the queue registry feature. The queue registry is provided as a
2142 means for kernel aware debuggers to locate queue definitions. It has no
2143 purpose unless you are using a kernel aware debugger. The queue registry
2144 will only be used when configQUEUE_REGISTRY_SIZE is greater than zero.
2145 + Added the ST Cortex-M3 drivers into the Demo/Common/Drivers directory to
2146 prevent them from having to be included in multiple demos.
2147 + Added a Keil STM32 demo application.
2148 + Changed the blocktim.c test files as it is no longer legitimate for all
2149 ports to call queue API functions from within a critical section.
2150 + Added the IntQueue.c test file to test the calling of queue API functions
2151 from different interrupt priority levels, and test interrupt nesting.
2153 Changes between V5.0.0 and V5.0.1
2155 + V5.0.1 was a customer specific release.
2157 Changes between V4.8.0 and V5.0.0 released April 15, 2008
2159 *** VERY IMPORTANT INFORMATION ON UPGRADING TO FREERTOS.ORG V5.0.0 ***
2161 The parameters to the functions xQueueSendFromISR(), xQueueSendToFrontFromISR(),
2162 xQueueSendToBackFromISR() and xSemaphoreGiveFromISR() have changed. You must
2163 update all calls to these functions to use the new calling convention! Your
2164 compiler might not issue any type mismatch warnings!
2169 + Support added for the new Luminary Micro LM3S3768 and LM3S3748 Cortex-M3
2171 + New task hook feature added.
2172 + PowerPC demo updated to use version 10.1 of the Xilinx EDK.
2173 + Efficiency gains within the PIC32 port layer.
2175 Changes between V4.7.2 and V4.8.0 released March 26 2008
2177 + Added a Virtex4 PowerPC 405 port and demo application.
2178 + Added optional stack overflow checking and new
2179 uxTaskGetStackHighWaterMark() function.
2180 + Added new xQueueIsQueueEmptyFromISR(), xQueueIsQueueFullFromISR() and
2181 uxQueueMessagesWaitingFromISR() API functions.
2182 + Efficiency improvements to the Cortex-M3 port layer. NOTE: This
2183 requires that an SVC handler be installed in the application.
2184 + Efficiency improvements to the queue send and receive functions.
2185 + Added new trace macros. These are application definable to provide
2186 a flexible trace facility.
2187 + Implemented the configKERNEL_INTERRUPT_PRIORITY within the Keil Cortex
2188 M3 port layer (bringing it up to the same standard as the IAR and GCC
2190 + Ports that used the arm-stellaris-eabi-gcc tools have been converted to
2191 use the arm-non-eabi-gcc tools.
2193 Changes between V4.7.1 and V4.7.2 released February 21, 2008
2195 + Added Fujitsu MB91460 port and demo.
2196 + Added Fujitsu MB96340 port and demo.
2197 + Tidied up the capitalisation of include files to facilitate builds on
2199 + Removed some redundant casting that was generating warnings - but was
2200 included to remove warnings on other compilers.
2202 Changes between V4.7.0 and V4.7.1 released February 3, 2008
2204 + Updated all IAR ARM projects to use V5.11 of the IAR Embedded Workbench
2206 + Introduced recursive semaphore feature.
2207 + Updated LPC2368 demos to take into account silicon bugs in old chip
2209 + Updated STR9 uIP port to manually set the net mask and gateway addresses.
2210 + Updating demos to allow more to run with the co-operative scheduler.
2211 + Fixed co-operative scheduler behaviour upon the occurrence of a tick
2212 interrupt while the scheduler was suspended.
2213 + Updated documentation contained within semphr.h.
2214 + ARM7 GCC ports no longer use the IRQ attribute.
2216 Changes between V4.6.1 and V4.7.0 released December 6, 2007
2218 + Introduced the counting semaphore macros and demo source files. The
2219 Open Watcom PC project has been updated to include the new demo. See
2220 the online documentation for more information.
2221 + Introduced the 'alternative' queue handling API and demo source files.
2222 The Open Watcom PC project has been updated to include the new demo
2223 source files. See the online documentation for more information.
2224 + Added AT91SAM7X Eclipse demo project.
2225 + Added the STM32 primer demo project for the GCC compiler and Ride IDE.
2226 + Removed the .lock files that were mistakenly included in the V4.6.1
2229 Changes between V4.6.0 and V4.6.1 released November 5 2007
2231 + Added support for the MIPS M4K based PIC32.
2232 + Added 'extern "C"' to all the header files to facilitate use with C++.
2234 Changes between V4.5.0 and V4.6.0 released October 28 2007
2236 + Changed the method used to force a context switch within an ISR for the
2237 ARM7/9 GCC ports only. The portENTER_SWITCHING_ISR() and
2238 portEXIT_SWITCHING_ISR() macros are no longer supported. This is to
2239 ensure correct behaviour no matter which GCC version is used, with or
2240 without the -fomit-frame-pointer option, and at all optimisation levels.
2241 + Corrected the prototype for xQueueGenericSend() within queue.h.
2243 Changes between V4.4.0 and V4.5.0 released September 17 2007
2245 + Added the xQueueSendToFront(), xQueueSendToBack() and xQueuePeek()
2246 functionality. These should now be used in preference to the old
2247 xQueueSend() function - which is maintained for backward compatibility.
2248 + Added Mutex functionality. The behaviour of mutexes is subtly different
2249 to the already existing binary semaphores as mutexes automatically
2250 include a priority inheritance mechanism.
2251 + Added the GenQTest.c and QPeek.c to test and demonstrate the behaviour
2252 of the new functionality.
2253 + Updated the LM3Sxxxx and PC ports to include the new GenQTest.c and
2255 + Updated the GCC port for the Cortex M3 to include the
2256 configKERNEL_INTERRUPT_PRIORITY functionality. This was previously only
2257 included in the IAR port.
2258 + Optimised the GCC and IAR port layer code - specifically the context
2260 + Consolidated the LM3Sxxxx EK demos for all development tools into a
2261 single project that automatically detects which version of the EK the
2262 application is executing on.
2263 + Added Eclipse support for LM3Sxxxx evaluation kits.
2264 + Added Eclipse support for the Keil LPC2368 evaluation kit.
2265 + Added the Demo/Drivers directory to hold code that is common to multiple
2266 demo application projects.
2267 + Included some minor bug fixes in the uIP 1.0 code.
2268 + Added an lwIP demo for the STR9 - thanks ST for assistance.
2269 + Updated the AVR32 port to ensure correct behaviour with full compiler
2271 + Included binaries for OpenOCD FTDI and parallel port interfaces.
2273 Changes between V4.4.0 and V4.3.1 released July 31, 2007
2275 + Added AVR32 UC3B demo application.
2276 + Updated AVR32 UC3A port and demo applications.
2277 + Added IAR lwIP demo for AVR32 UC3A.
2278 + Updated listGET_OWNER_OF_NEXT_ENTRY() to assist compiler optimisation
2279 (thanks Niu Yong for making the suggestion).
2280 + Added xTaskGetSchedulerState() API function.
2281 + BUG FIX: Corrected behaviour when tasks that are blocked indefinitely
2282 have their block time adjusted (within xQueueSend() and xQueueReceive()),
2283 and are the subject of a call the vTaskResume() when they are not
2284 actually in the Suspended state (thanks Dan Searles for reporting the
2288 Changes between V4.3.0 and V4.3.1 released June 11, 2007
2290 + Added STMicroelectronics STM32 Cortex-M3 demo application.
2291 + Updated ustdlib.c for the GCC LM3S6965 demo.
2293 Changes between V4.2.1 and V4.3.0 released June 5, 2007
2295 + Introduced configKERNEL_INTERRUPT_PRIORITY to the IAR Cortex-M3, PIC24
2296 and dsPIC ports. See the LM3S6965 and PIC24 demo application
2297 documentation pages for more information.
2298 + Updated the PIC24 and dsPIC demos to build with V3.0 of the PIC30 GCC
2299 tools, and changed the demo applications.
2300 + Added demos for the new Ethernet and CAN enabled Luminary Micro Stellaris
2302 + Corrected bug in uIP the demos that prevented frames of approximately 1480
2303 bytes and over from being transmitted.
2304 + Included the LPC2368/uIP/Rowley demo into the main FreeRTOS.org
2306 + Update to WizC PIC18 port to permit its use with version 14 of the
2307 compiler. Thanks Marcel!
2309 Changes between V4.2.1 and V4.2.0 released April 2, 2007
2311 + Added AVR32 AT32UC3A ports for GCC and IAR.
2312 + Added -fomit-frame-pointer option to lwIP SAM7X demo makefile.
2313 + Moved location of call to LCD_Init() in STR9 demo to ensure it is only
2314 called after the scheduler has been started.
2316 Changes between V4.1.3 and V4.2.0 released February 8, 2007
2318 + Changes to both task.c and queue.c as a result of testing performed on
2319 the SafeRTOS code base.
2320 + Added Cortex-M3 LM3S811 demos for GCC and IAR tools.
2322 Changes between V4.1.2 and V4.1.3 released November 19, 2006
2324 + Added STR750 ARM7 port using the Raisonance RIDE/GCC tools.
2325 + Added -fomit-frame-pointer option to Rowley ARM7 demos as work around
2326 to GCC bug at some optimisation levels.
2327 + Altered the way the heap is defined in the LM3S811 Keil demo to prevent
2328 the RAM usage from counting toward the code size limit calculation.
2329 + CO-ROUTINE BUG FIX: Removed the call to prvIsQueueEmpty from within
2330 xQueueCRReceive as it exited with interrupts enabled. Thanks Paul Katz.
2331 + Tasks that block on events with a timeout of portMAX_DELAY are now
2332 blocked indefinitely if configINCLUDE_vTaskSuspend is defined.
2333 Previously portMAX_DELAY was just the longest block time possible. This
2334 is still the case if configINCLUDE_vTaskSuspend is not defined.
2335 + Minor changes to some demo application files.
2337 Changes between V4.1.1 and V4.1.2 released October 21, 2006
2339 + Added 16bit PIC ports and demos.
2340 + Added STR750 port and demo.
2343 Changes between V4.1.0 and V4.1.1 released September 24, 2006
2345 + Added the Luminary Micro Stellaris LM3S811 demo application.
2347 Changes between V4.0.5 and V4.1.0 released August 28, 2006
2349 + Prior to V4.1.0, under certain documented circumstances, it was possible
2350 for xQueueSend() and xQueueReceive() to return without having completed
2351 and without their block time expiring. The block time effectively
2352 stated a maximum block time, and the return value of the function needed
2353 to be checked to determine the reason for returning. This is no longer
2354 the case as the functions will only return once the block time has
2355 expired or they are able to complete their operation. It is therefore no
2356 longer necessary to wrap calls within loops.
2357 + Changed the critical section handling in the IAR AVR port to correct the
2358 behaviour when used with later compiler versions.
2359 + Added the LPC2138 CrossWorks demo into the zip file. Previously this was
2360 only available as a separate download.
2361 + Modified the AVR demo applications to demonstrate the use of co-routines.
2363 Changes between V4.0.4 and V4.0.5 released August 13, 2006
2365 + Introduced API function xTaskResumeFromISR(). Same functionality as
2366 xTaskResume(), but can be called from within an interrupt service routine.
2367 + Optimised vListInsert() in the case when the wake time is the maximum
2369 + Bug fix: The 'value' of the event list item is updated when the priority
2370 of a task is changed. Previously only the priority of the TCB itself was
2372 + vTaskPrioritySet() and vTaskResume() no longer use the event list item.
2373 This has not been necessary since V4.0.1 when the xMissedYield handling
2375 + Lowered the PCLK setting on the ARM9 STR9 demo from 96MHz to 48MHz.
2376 + When ending the scheduler - do not try to attempt a context switch when
2377 deleting the current task.
2378 + SAM7X EMAC drivers: Corrected the Rx frame length mask when obtaining
2379 the length from the rx descriptor.
2382 Changes between V4.0.3 and V4.0.4 released June 22, 2006
2384 + Added a port and demo application for the STR9 ARM9 based processors from
2386 + Slight optimisation to the vTaskPrioritySet() function.
2387 + Included the latest uIP version (1.0) in the demo/common/ethernet
2390 Changes between V4.0.2 and V4.0.3 released June 7, 2006
2392 + Added a port and demo application for the Cortex-M3 target using the IAR
2394 + The ARM Cortex-m3 Rowley projects have been updated to use V1.6 of the
2396 + The heap size defined for the lwIP Rowley demo has been reduced so that
2397 the project will link correctly when using the command line GCC tools
2398 also. The makefile has also been modified to allow debugging.
2399 + The lwIP Rowley demo not includes a 'kernel aware' debug window.
2400 + The uIP Rowley project has been updated to build with V1.6 of CrossWorks.
2401 + The second set of tasks in the blockQ demo were created the wrong way
2402 around (inconsistent to the description in the file). This has been
2405 Changes between V4.0.1 and V4.0.2 released May 28, 2006
2407 + Port and demo application added for the Tern Ethernet Engine controller.
2408 + Port and demo application added for MC9S12 using GCC, thanks to
2409 Jefferson "imajeff" Smith.
2410 + The function vTaskList() now suspends the scheduler rather than disabling
2411 interrupts during the creation of the task list.
2412 + Allow a task to delete itself by passing in its own handle. Previously
2413 this could only be done by passing in NULL.
2414 + Corrected the value passed to the WDG_PeriodValueConfig() library
2415 function in the STR71x demo.
2416 + The tick hook function is now called only within a tick isr. Previously
2417 it was also called when the tick function was called during the scheduler
2419 + The EMAC driver in the SAM7X lwIP demo has been made more robust as per
2420 the thread: https://sourceforge.net/forum/message.php?msg_id=3714405
2421 + In the PC ports: Add function prvSetTickFrequencyDefault() to set the
2422 DOS tick back to its proper value when the scheduler exits. Thanks
2424 + In the Borland x86 ports there was a mistake in the portFIRST_CONTEXT
2425 macro where the BP register was not popped from the stack correctly. The
2426 BP value would never get used so this did not cause a problem, but it has
2427 been corrected all the same.
2430 Changes between V4.0.0 and V4.0.1 released April 7 2006
2432 + Improved the ARM CORTEX M3 ports so they now only have to service
2434 + Added a Luminary Micro port and demo for use with Rowley CrossWorks.
2435 + Added the xMissedYield handling to tasks.c.
2437 Changes between V3.2.4 and V4.0.0
2441 + Added new RTOS port for Luminary Micros ARM CORTEX M3 microcontrollers.
2442 + Added new co-routine functionality.
2444 Other kernel changes:
2446 + An optional tick hook call is now included in the tick function.
2447 + Introduced the xMiniListItem structure and removed the list pxHead
2448 member in order to reduce RAM usage.
2449 + Added the following definitions to the FreeRTOSConfig.h file included
2452 configUSE_CO_ROUTINES
2453 configMAX_CO_ROUTINE_PRIORITIES
2454 + The volatile qualification has been changed on the list members to allow
2455 the task.c code to be tidied up a bit.
2456 + The scheduler can now be started even if no tasks have been created!
2457 This is to allow co-routines to run when there are no tasks.
2458 + A task being woken by an event will now preempt the currently running task
2459 even if its priority is only equal to the currently running task.
2461 Port and demo application changes:
2463 + Updated the WinAVR demo to compile with the latest version of WinAVR
2464 with no warnings generated.
2465 + Changed the WinAVR makefile to make chars signed - needed for the
2466 co-routine code if BaseType_t is set to char.
2467 + Added new demo application file crflash.c. This demonstrates co-routine
2468 functionality including passing data between co-routines.
2469 + Added new demo application file crhook.c. This demonstrates co-routine
2470 and tick hook functionality including passing data between and ISR and
2472 + Some NOP's were missing following stmdb{}^ instructions in various ARM7
2473 ports. These have been added.
2474 + Updated the Open Watcom PC demo project to include the crflash and crhook
2475 demo co-routines as an example of their use.
2476 + Updated the H8S demo to compile with the latest version of GCC.
2477 + Updated the SAM7X EMAC drivers to take into account the hardware errata
2478 regarding lost packets.
2479 + Changed the default MAC address used by some WEB server demos as the
2480 original addresses used was not liked by some routers.
2481 + Modified the SAM7X/IAR startup code slightly to prevent it hanging on
2482 some systems when the code is executed using a j-link debugger. The
2483 j-link macro file configures the PLL before the code executes so
2484 attempting to configure it again in the startup code was causing a
2485 problem for some user. Now a check is performed first to see if the
2486 PLL is already set up.
2487 + GCC port now contain all assembler code in a single asm block rather than
2488 individual blocks as before.
2489 + GCC LPC2000 code now explicitly uses R0 rather than letting the assembler
2490 choose the register to use as a temporary register during the context
2492 + Added portNOP() macro.
2493 + The compare match load value on LPC2000 ports now has 1 added to correct
2495 + The minimal stack depth has been increased slightly on the WIZC PIC18
2498 Changes between V3.2.3 and V3.2.4
2500 + Modified the GCC ARM7 port layer to allow use with GCC V4.0.0 and above.
2501 Many thanks to Glen Biagioni for the provided update.
2502 + Added a new Microblaze port and demo application.
2503 + Modified the SAM7X EMAC demo to default to use the MII interface rather
2504 than the RMII interface.
2505 + Modified the startup sequence of the SAM7X demo slightly to allow the
2506 EMAC longer to auto negotiate.
2508 Changes between V3.2.2 and V3.2.3
2510 + Added MII interface support to the SAM7X EMAC peripheral driver.
2511 Previously versions worked with the RMII interface only.
2512 + Added command line GCC support to the SAM7X lwIP demo. Previously the
2513 project could only be built using the CrossWorks IDE. Modifications to
2514 this end include the addition of a standard makefile and linker script to
2515 the download, and some adjustments to the stacks allocated to each task.
2516 + Changed the page returned by the lwIP WEB server demo to display the
2517 task status table rather than the TCP/IP statistics.
2518 + Corrected the capitalisation of some header file includes and makefile
2519 dependencies to facilitate use on Linux host computers.
2520 + The various LPC2000 ports had a mistake in the timer setup where the
2521 prescale value was written to T0_PC instead of T0_PR. This would have
2522 no effect unless a prescale value was actually required. This has been
2525 Changes between V3.2.1 and V3.2.2 - Released 23 September, 2005
2527 + Added an IAR port for the Philips LPC2129
2528 + The Atmel ARM7 IAR demo project files are now saved in the IAR Embedded
2529 Workbench V4.30a format.
2530 + Updated the J-Link macro file included with the SAM7X uIP demo project
2531 to allow the demo board to be reset over the J-Link.
2533 Changes between V3.2.0 and V3.2.1 - Released 1 September, 2005
2535 + Added lwIP demo for AT91SAM7X using Rowley tools.
2536 + Added uIP demo for AT91SAM7X using IAR tools.
2537 + Added function xTaskGetCurrentTaskHandle().
2538 + Renamed events.h to mevents.h to prevent it conflicting with the events.h
2539 generated automatically by the HCS12 processor expert utility. events.h
2540 is only used by the PC demo application.
2541 + Both PIC18 ports now initialise the TBLPTRU to 0 as this is the value
2542 expected by the compiler, and the compilers do not write to this
2544 + The HCS12 banked model demo now creates the 'suicide' tasks immediately
2545 prior to starting the scheduler. These tasks should be the last tasks to
2546 get started in order for the test to function correctly.
2548 Changes between V3.1.1 and V3.2.0 - Released 29 June, 2005
2550 V3.2.0 introduces two new MSP430 ports and corrects a minor kernel
2551 issues. Thanks to Ares.qi for his input.
2553 + Added two MSP430 ports that use the Rowley CrossWorks development tools.
2554 One port just mirrors the existing GCC port. The other port was provided
2555 by Milos Prokic. Thanks!
2556 + V3.2.0 corrects the behavior when vTaskPrioritySet() or vTaskResume()
2557 are called while the scheduler is locked (by a call to
2558 vTaskSuspendAll()). When this is done the subject task now starts to
2559 execute immediately when the scheduler is unlocked if it has the highest
2560 priority that is ready to run. Previously there was a possibility that
2561 the task would not run until the next RTOS tick or call to portYIELD().
2562 + Another similar small correction ensures that in the case where more than
2563 one task is blocked on a semaphore or queue, the task with the highest
2564 priority is guaranteed to be unblocked first.
2565 + Added a couple of more test tasks to the PC demo which cover the points
2568 Changes between V3.1.0 and V3.1.1 - Released 21st June, 2005
2570 This release updates the HCS12 port. The common kernel code
2573 + Updated the HCS12 port to support banking and introduced a demo
2574 application for the MC9S12DP256. The new demo application is
2575 located in the Demo/HCS12_CodeWarrior_banked directory.
2576 + The name of the directory containing the MC9S12F32 demo application
2577 has been changed to Demo/HCS12_CodeWarrior_small (as in 'small'
2579 + MC9S12F32 demo updated slightly to use the PLL. The CPU speed for the
2580 demo application is now 24MHz. Previously it was 8MHz.
2581 + The demo application file Demo/Common/Minimal/death.c has a slight
2582 alteration to prevent it using floating point variables.
2585 Changes between V3.0.0 and V3.1.0 - Released 11th June, 2005
2587 + Added new ports for ST Microsystems STR71x, and Freescale HCS12
2588 microcontrollers. Currently the HCS12 port is limited to the small
2589 memory model. Large memory models will be supported in the next
2591 + PIC18 wizC port updated. Thanks to Marcel van Lieshout for his
2592 continuing contribution.
2593 + The accuracy of the AVR port timer setup has been improved. Thanks to
2594 Thomas Krutmann for this contribution.
2595 + Added a new conditional compilation macro configIDLE_SHOULD_YIELD.
2596 See the WEB documentation for details.
2597 + Updated the CrossWorks uIP demo to build with V1.4 of CrossWorks.
2598 + Slight modification to the SAM7 release build configuration to correct
2599 an include path definition.
2600 + Updated the MPLAB PIC18 documentation to provide extra details on linker
2603 Changes between V3.0.0 and V2.6.1 - Released 23rd April, 2005
2605 V3.0.0 includes many enhancements, so this history list is broken into
2606 subsections as follows:
2610 Directory name changes
2611 Kernel and miscellaneous changes changes
2615 + Each port now defines BaseType_t as the data type that is most
2616 efficient for that architecture. The type BaseType_t is used
2617 extensively in API calls necessitating the following changes to the
2618 FreeRTOS API function prototypes.
2620 See the "New for V3.0.0" section of the FreeRTOS online
2621 documentation for full details of API changes.
2625 + The AT91FR40008 ARM7 port contributed by John Feller is now included
2626 in the download (thanks John!).
2627 + The PIC18 port for the wizC/fedC compiler contributed by Marcel van
2628 Lieshout is now included in the download (thanks Marcel!).
2629 + The IAR port for the AVR microcontroller has been upgraded to V3.0.0
2630 and is now a supported port.
2632 - Directory name changes
2634 For consistency, and to allow integration of the new ports, the
2635 following directory names have been changed.
2637 + The source/portable/GCC/ARM7 directory has been renamed
2638 source/portable/GCC/ARM7_LPC2000 so it is compatible with the naming
2639 of other GCC ARM7 ports.
2640 + The Demo/PIC directory has been renamed Demo/PIC18_MPLAB to
2641 accommodate the wizC/fedC PIC port.
2642 + The demo applications for the two AVR ports no longer share the same
2643 directory. The WinAVR demo is in the Demo/AVR_ATMega323_WinAVR
2644 directory and the IAR port in the Demo/AVR_ATMega323_IAR directory.
2647 - Kernel and miscellaneous changes changes
2649 See the "New for V3.0.0" section of the FreeRTOS online
2650 documentation for more information.
2652 + Previously 'portmacro.h' contained some user editable definitions
2653 relating to the user application, and some fixed definitions relating
2654 specifically to the port being used. The application specific
2655 definitions have been removed from 'portmacro.h' and placed inside a
2656 new header file called 'FreeRTOSConfig.h'. 'portmacro.h' should now
2657 never be modified by the user. A 'FreeRTOSConfig.h' is now included
2658 in each of FreeRTOS/Demo subdirectories - as it's settings relate to
2659 the demo application rather than being specific to the port.
2660 + Introduced configUSE_IDLE_HOOK in idle task.
2661 + The idle task will yield when another idle priority task is ready to
2662 run. Previously the idle task would run to the end of its time slice
2664 + The idle task is now created when the scheduler is started. This
2665 requires less stack than the previous scheme where it was created upon
2666 creation of the first application task.
2667 + The function usPortCheckFreeStackSpace() has been renamed
2668 usTaskCheckFreeStackSpace() and moved from the portable layer to
2670 + Corrected spelling of portMINMAL_STACK_SIZE to portMINIMAL_STACK_SIZE.
2671 + The portheap.c file included with the AVR port has been deleted. The
2672 AVR demo now uses the standard heap1 sample memory allocator.
2673 + The GCC AVR port is now build using the standard make utility. The
2674 batch files used previously have been deleted. This means a recent
2675 version of WinAVR is required in order to create a binary suitable for
2676 source level debugging.
2677 + vTaskStartScheduler() no longer takes the configUSE_PREEMPTION
2678 constant as a parameter. Instead the constant is used directly within
2679 tasks.c and no parameter is required.
2680 + The header file 'FreeRTOS.h' has been created and is used to include
2681 'projdefs.h', 'FreeRTOSConfig.h' and 'portable.h' in the necessary
2682 order. FreeRTOS.h can now be included in place of these other
2684 + The header file 'errors.h' has been deleted. The definitions it
2685 contained are now located within 'projdefs.h'.
2686 + pvPortMalloc() now takes a size_t parameter as per the ANSI malloc().
2687 Previously an unsigned short was used.
2688 + When resuming the scheduler a yield is performed if either a tick has
2689 been missed, or a task is moved from the pending ready list into a
2690 ready list. Previously a yield was not performed on this second
2692 + In heap1.c an overflow check has been added to ensure the next free
2693 byte variable does not wrap around.
2694 + Introduced the portTASK_FUNCTION() and portTASK_FUNCTION_PROTO()
2696 + The MPLAB PIC port now saved the TABLAT register in interrupt service
2699 Changes between V2.6.0 and V2.6.1 - Released Feb 22, 2005
2701 This version adds support for the H8 processor.
2705 + tskMAX_TASK_NAME_LEN removed from the task.h header and added to each
2706 individual portmacro.h file as portMAX_TASK_NAME_LEN. This allows RAM
2707 limited ports to allocate fewer characters to the task name.
2708 + AVR port - Replaced the inb() and outb() functions with direct memory
2709 access. This allows the port to be built with the 20050414 build of
2711 + GCC LPC2106 port - removed the 'static' from the definition of
2712 vNonPreemptiveTick() to allow the demo to link when using the cooperative
2714 + GCC LPC2106 port - Corrected the optimisation options in the batch files
2715 ROM_THUMB.bat, RAM_THUMB.bat, ROM_ARM.bat and RAM_ARM.bat. The lower case
2716 -o is replaced by an uppercase -O.
2717 + Tasks.c - The strcpy call has been removed when copying across the task
2719 + Updated the trace visualisation to always be 4 byte aligned so it can be
2720 used on ARM architectures.
2721 + There are now two tracecon executables (that convert the trace file binary
2722 into an ASCII file). One for big endian targets and one for little endian
2724 + Added ucTasksDeleted variable to prevent vTaskSuspendAll() being called
2725 too often in the idle task.
2726 + SAM7 USB driver - Replaced the duplicated RX_DATA_BK0 in the interrupt
2727 mask with the RX_DATA_BK1.
2730 Changes between V2.5.5 and V2.6.0 - Released January 16, 2005
2732 + Added the API function vTaskDelayUntil(). The demo app file
2733 Demo/Common/Minimal/flash.c has been updated to demonstrate its use.
2734 + Added INCLUDE_vTaskDelay conditional compilation.
2735 + Changed the name of the Demo/ARM7_AtmelSAM7S64_IAR directory to
2736 Demo/ARM7_AT91SAM7S64_IAR for consistency.
2737 + Modified the AT91SAM7S USB driver to allow descriptors that have
2738 a length that is an exact multiple of the FIFO to be transmitted.
2740 Changes between V2.5.4 and V2.5.5 - Released January 3, 2005
2742 This version adds support for the Atmel SAM7 ARM7 microcontrollers
2743 along with the IAR development tools.
2747 + Renamed the Demo/ARM7 directory to Demo/ARM7_LPC2106_GCC.
2748 + Renamed the Demo/ARM7_Keil directory to Demo/ARM7_LPC2129_Keil.
2749 + Modified the Philips ARM7 serial interrupt service routines to only
2750 process one interrupt per call. This seems to enable the ISR to
2751 operate more quickly.
2752 + Removed the 'far' keyword from the Open Watcom portable layer source
2753 files. This allows their use with V1.3 of Open Watcom.
2754 + Minor modifications to the SDCC build files to allow their use under
2755 Linux. Thanks to Frieder Ferlemann for this contribution.
2756 + Small change to sTaskCreate() to allow a context switch even when
2757 pxCreatedTask is NULL. Thanks to Kamil for this contribution.
2758 + inline keyword removed from vTaskSwitchContext() and VTaskIncrementTick()
2761 Changes between V2.5.3 and V2.5.4 - Released Dec 1, 2004
2763 This is an important maintenance release.
2765 The function cTaskResumeAll() has been modified so it can be used safely
2766 prior to the kernel being initialised. This was an issue as
2767 cTaskResumeAll() is called from pvPortMalloc(). Thanks to Daniel Braun
2768 for highlighting this issue.
2770 Changes between V2.5.2 and V2.5.3 - Released Nov 2, 2004
2772 The critical section handling functions have been changed for the GCC ARM7
2773 port. Some optimisation levels use the stack differently to others. This
2774 means the interrupt flags cannot always be stored on the stack and are
2775 instead now stored in a variable, which is then saved as part of the
2776 tasks context. This allows the GCC ARM7 port to be used at all
2777 optimisation levels - including -Os.
2779 Other minor changes:
2781 + MSP430 definition of usCriticalNesting now uses the volatile qualifier.
2782 This is probably not required but added just in case.
2784 Changes between V2.5.1 and V2.5.2 - Released Oct 26, 2004
2786 + Added the Keil ARM7 port.
2787 + Slight modification to comtest.c to make the delay periods more random.
2788 This creates a better test condition.
2790 Changes between V2.5.0 and V2.5.1 - Released Oct 9, 2004
2792 + Added the MSP430 port.
2793 + Extra comments added to the GCC ARM7 port.c and portISR.c files.
2794 + The memory pool allocated within heap_1.c has been placed within a
2795 structure to ensure correct memory alignment on 32bit systems.
2796 + Within the GCC ARM7 serial drivers an extra check is made to ensure
2797 the post to the queue was successful if then attempting immediately
2798 retrieve the posted character.
2799 + Changed the name of the constant portTICKS_PER_MS to portTICK_PERIOD_MS
2800 as the old name was misleading.
2803 Changes between V2.4.2 and V2.5.0 - Released Aug 12, 2004
2805 The RTOS source code download now includes three separate memory allocation
2806 schemes - so you can choose the most appropriate for your application.
2807 These are found in the Source/Portable/MemMang directory. The demo
2808 application projects have also been updated to demonstrate the new schemes.
2809 See the "Memory Management" page of the API documentation for more details.
2811 + Added heap_1.c, heap_2.c and heap_3.c in the Source/Portable/MemMang
2813 + Replaced the portheap.c files for each demo application with one of the
2814 new memory allocation files.
2815 + Updated the portmacro.h file for each demo application to include the
2816 constants required for the new memory allocators: portTOTAL_HEAP_SIZE and
2818 + Added a new test to the ARM7 demo application that tests the operation
2819 of the heap_2 memory allocator.
2822 Changes between V2.4.1 and V2.4.2 - Released July 14, 2004
2824 + The ARM7 port now supports THUMB mode.
2825 + Modification to the ARM7 demo application serial port driver.
2827 Changes between V2.4.0 and V2.4.1 - Released July 2, 2004
2829 + Rationalised the ARM7 port version of portEXIT_CRITICAL() -
2830 improvements provided by Bill Knight.
2831 + Made demo serial driver more complete and robust.
2834 Changes between V2.4.0 and V2.3.1 - Released June 30, 2004
2836 + Added the first ARM7 port - thanks to Bill Knight for the assistance
2838 + Added extra files to the Demo/Common/Minimal directory. These are
2839 equivalent to their Demo/Common/Full counterparts but with the
2840 calls to the functions defined in print.c removed.
2841 + Added TABLAT to the list of registers saved as part of a PIC18 context.
2843 Changes between V2.3.0 and V2.3.1 - Released June 25, 2004
2845 + Changed the way the vector table is defined to be more portable.
2846 + Corrected the definitions of SPH and SPL in portmacro.s90.
2847 The previous definitions prevented V2.3.0 operating if the iom323.h
2848 header file was included in portmacro.s90.
2850 Changes between V2.2.0 and V2.3.0 - Released June 19, 2004
2852 + Added an AVR port that uses the IAR compiler.
2853 + Explicit use of 'signed' qualifier on plain char types.
2854 + Modified the Open Watcom project files to use 'signed' as the
2856 + Changed odd calculation of initial pxTopOfStack value when
2857 portSTACK_GROWTH < 0.
2858 + Added inline qualifier to context switch functions within task.c.
2859 Ports that do not support the (non ANSI) inline keyword have the
2860 inline #define'd away in their respective portmacro.h files.
2862 Changes between V2.1.1 and V2.2.0 - Released May 18, 2004
2864 + Added Cygnal 8051 port.
2865 + PCLATU and PCLATH are now saved as part of the PIC18 context. This
2866 allows function pointers to be used within tasks. Thanks to Javier
2867 Espeche for the enhancement.
2868 + Minor changes to demo application files to reduce stack usage.
2869 + Minor changes to prevent compiler warnings when compiling the new port.
2871 Changes between V2.1.0 and V2.1.1 - Released March 12, 2004
2873 + Bug fix - pxCurrentTCB is now initialised before the call to
2874 prvInitialiseTaskLists(). Previously pxCurrentTCB could be accessed
2875 while null during the initialisation sequence. Thanks to Giuseppe
2876 Franco for the correction.
2878 Changes between V2.0.0 and V2.1.0 - Released Feb 29, 2004
2880 V2.1.0 has significant reworks that greatly reduce the amount of time
2881 the kernel has interrupts disabled. The first section of modifications
2882 listed here must be taken into account by users. The second section
2883 are related to the kernel implementation and as such are transparent.
2887 + The typedef TickType_t has been introduced. All delay times should
2888 now use a variable of type TickType_t in place of the unsigned long's
2889 used previously. API function prototypes have been updated
2891 + The configuration macro USE_16_BIT_TICKS has been introduced. If set
2892 to 1 TickType_t is defined as an unsigned short. If set to 0
2893 TickType_t is defined as an unsigned long. See the configuration
2894 section of the API documentation for more details.
2895 + The configuration macro INCLUDE_vTaskSuspendAll is now obsolete.
2896 + vTaskResumeAll() has been renamed cTaskResumeAll() as it now returns a
2897 value (see the API documentation).
2898 + ulTaskGetTickCount() has been renamed xTaskGetTickCount() as the type
2899 it returns now depends on the USE_16_BIT_TICKS definition.
2900 + cQueueReceive() must now >never< be used from within an ISR. Use the new
2901 cQueueReceiveFromISR() function instead.
2905 + A mechanism has been introduced that allows a queue to be accessed by
2906 a task and ISR simultaneously.
2907 + A "pending ready" queue has been introduced that enables interrupts to
2908 be processed when the scheduler is suspended.
2909 + The list implementation has been improved to provide faster item
2911 + The scheduler now makes use of the scheduler suspend mechanism in places
2912 where previously interrupts were disabled.
2914 Changes between V1.2.6 and V2.0.0 - Released Jan 31, 2004
2916 + Introduced new API functions:
2923 + Added conditional compilation options that allow the components of the
2924 kernel that are unused by an application to be excluded from the build.
2925 See the Configuration section on the WEB site for more information (on
2926 the API pages). The macros have been added to each portmacro.h file (
2927 sometimes called prtmacro.h).
2928 + Rearranged tasks.c.
2929 + Added demo application file dynamic.c.
2930 + Updated the PC demo application to make use of dynamic.c.
2931 + Updated the documentation contained in the kernel header files.
2932 + Creating a task now causes a context switch if the task being created
2933 has a higher priority than the calling task - assuming the kernel is
2935 + vTaskDelete() now only causes a context switch if the calling task is
2936 the task being deleted.
2938 Changes between V1.2.5 and V1.2.6 - Released December 31, 2003
2940 Barring the change to the interrupt vector (PIC port) these are minor
2943 + The interrupt vector used for the PIC master ISR has been changed from
2944 0x18 to 0x08 - where it should have always been. The incorrect address
2945 still works but probably executes a number of NOP's before getting to the
2947 + Changed the baud rate used by the AVR demo application to 38400. This
2948 has an error percentage of less than one percent with an 8MHz clock.
2949 + Raised the priority of the Rx task in demo\full\comtest.c. This only
2950 affects the Flashlite and PC ports. This was done to prevent the Rx
2951 buffer becoming full.
2952 + Reverted the Flashlite COM port driver back so it does not use the DMA.
2953 The DMA appears to miss characters under stress. The Borland Flashlite
2954 port was also calculating a register value incorrectly resulting in the
2955 wrong DMA source address being used. The same code worked fine when
2956 compiling with Open Watcom. Other minor enhancements were made to the
2958 + Modified the PIC serial Rx ISR to check for and clear overrun errors.
2959 Overrun errors seem to prevent any further characters being received.
2960 + The PIC demo projects now have some optimisation switched on.
2963 Changes between V1.2.4 and V1.2.5
2965 Small fix made to the PIC specific port.c file described below.
2967 + Introduced portGLOBAL_INTERRUPT_FLAG definition to test the global
2968 interrupt flag setting. Using the two bits defined within
2969 portINITAL_INTERRUPT_STATE was causing the w register to get clobbered
2970 before the test was performed.
2972 Changes between V1.2.3 and V1.2.4
2974 V1.2.4 contains a release version of the PIC18 port.
2975 An optional exception has been included with the GPL. See the licensing
2976 section of www.FreeRTOS.org for details.
2978 + The function xPortInitMinimal() has been renamed to
2979 xSerialPortInitMinimal() and the function xPortInit() has been renamed
2980 to xSerialPortInit().
2981 + The function sSerialPutChar() has been renamed cSerialPutChar() and
2982 the function return type chaned to portCHAR.
2983 + The integer and flop tasks now include calls to tskYIELD(), allowing
2984 them to be used with the cooperative scheduler.
2985 + All the demo applications now use the integer and comtest tasks when the
2986 cooperative scheduler is being used. Previously they were only used with
2987 the preemptive scheduler.
2988 + Minor changes made to operation of minimal versions of comtest.c and
2990 + The ATMega port definition of portCPU_CLOSK_HZ definition changed to
2991 8MHz base 10, previously it base 16.
2995 Changes between V1.2.2a and V1.2.3
2997 The only change of any significance is to the license, which has changed
2998 from the Open Software License to the GNU GPL.
3000 The zip file also contains a pre-release version of the PIC18 port. This
3001 has not yet completed testing and as such does not constitute part of the
3002 V1.2.3 release. It is still however covered by the GNU GPL.
3004 There are minor source code changes to accommodate the PIC C compiler.
3005 These mainly involve more explicit casting.
3007 + sTaskCreate() has been modified slightly to make use of the
3008 portSTACK_GROWTH macro. This is required for the PIC port where the
3009 stack grows in the opposite direction to the other existing ports.
3010 + prvCheckTasksWaitingTermination() has been modified slightly to bring
3011 the decrementing of usCurrentNumberOfTasks within the critical section,
3012 where it should have been since the creation of an eight bit port.
3014 Changes between V1.2.2 and V1.2.2a
3016 The makefile and buildcoff.bat files included with the AVR demo application
3017 have been modified for use with the September 2003 build of WinAVR. No
3018 source files have changed.
3020 Changes between V1.2.1 and V1.2.2
3022 There are only minor changes here to allow the PC and Flashlite 186 ports
3023 to use the Borland V4.52 compiler, as supplied with the Flashlite 186
3026 + Introduced a BCC directory under source\portable. This contains all the
3027 files specific to the Borland compiler port.
3028 + Corrected the macro naming of portMS_PER_TICK to portTICKS_PER_MS.
3029 + Modified comtest.c to increase the rate at which the string is
3030 transmitted and received on the serial port. The Flashlite 186 demo
3031 app baud rate has also been increased.
3032 + The values of the constants used in both integer.c files have been
3033 increased to force the Borland compiler to use 32 bit values. The
3034 Borland optimiser placed the previous values in 16 bit registers, and in
3035 So doing invalidated the test.
3037 Changes between V1.2.0 and V1.2.1
3039 This version includes some minor changes to the list implementation aimed
3040 at improving the context switch time - with is now approximately 10% faster.
3041 Changes include the removal of some null pointer assignment checks. These
3042 were redundant where the scheduler uses the list functions, but means any
3043 user application choosing to use the same list functions must now check
3044 that no NULL pointers are passed as a parameter.
3046 The Flashlite 186 serial port driver has also been modified to use a DMA
3047 channel for transmissions. The serial driver is fully functional but still
3048 under development. Flashlite users may prefer to use V1.2.0 for now.
3052 + Changed the baud rate for the ATMega323 serial test from 19200 to 57600.
3053 + Use vSerialPutString() instead of single character puts in
3054 Demo\Full\Comtest.c. This allows the use of the flashlite DMA serial
3055 driver. Also the check variable only stops incrementing after two
3056 consecutive failures.
3057 + semtest.c creates four tasks, two of which operate at the idle priority.
3058 The tasks that operate at the idle priority now use a lower expected
3059 count than those running at a higher priority. This prevents the low
3060 priority tasks from signalling an error because they have not been
3061 scheduled enough time for each of them to count the shared variable to
3062 the higher original value.
3063 + The flashlite 186 serial driver now uses a DMA channel for transmissions.
3064 + Removed the volatile modifier from the list function parameters. This was
3065 only ever included to prevent compiler warnings. Now warnings are
3066 removed by casting parameters where the calls are made.
3067 + prvListGetOwnerOfNextEntry() and prvListGetOwnerOfHeadEntry() have been
3068 removed from list.c and added as macros in list.h.
3069 + usNumberOfItems has been added to the list structure. This removes the
3070 need for a pointer comparison when checking if a list is empty, and so
3072 + Removed the NULL check in vListRemove(). This makes the call faster but
3073 necessitates any application code utilising the list implementation to
3074 ensure NULL pointers are not passed.
3075 + Renamed portTICKS_PER_MS definition to portMS_PER_TICK (milli seconds
3076 per tick). This is what it always should have been.
3078 Changes between V1.01 and V1.2.0
3080 The majority of these changes were made to accommodate the 8bit AVR port.
3081 The scheduler workings have not changed, but some of the data types used
3082 have been made more friendly to an eight bit environment.
3086 + Changed the version numbering format.
3088 + Split the directory demo\common into demo\common\minimal and
3089 demo\common\full. The files in the full directory are for systems with
3090 a display (currently PC and Flashlite 186 demo's). The files in the
3091 minimal directory are for systems with limited RAM and no display
3092 (currently MegaAVR).
3093 + Minor changes to demo application function prototypes to make more use
3095 + Within the scheduler itself the following functions have slightly
3096 modified declarations to make use of 8bit data types where possible:
3100 usQueueMessageWaiting(),
3101 sQueueSendFromISR(),
3104 sSemaphoreGiveFromISR(),
3106 sTaskMoveFromEventList().
3108 Where the return type has changed the function name has also changed in
3109 accordance with the naming convention. For example
3110 usQueueMessageWaiting() has become ucQueueMessageWaiting().
3111 + The definition tskMAX_PRIORITIES has been moved from task.h to
3112 portmacro.h and renamed portMAX_PRIORITIES. This allows different
3113 ports to allocate a different maximum number of priorities.
3114 + By default the trace facility is off, previously USE_TRACE_FACILITY
3116 + comtest.c now uses a psuedo random delay between sends. This allows for
3117 better testing as the interrupts do not arrive at regular intervals.
3118 + Minor change to the Flashlite serial port driver. The driver is written
3119 to demonstrate the scheduler and is not written to be efficient.
3123 Changes between V1.00 and V1.01
3125 These changes improve the ports. The scheduler itself has not changed.
3127 Improved context switch mechanism used when performing a context
3128 switch from an ISR (both the tick ISR and the serial comms ISR's within
3129 the demo application). The new mechanism is faster and uses less stack.
3131 The assembler file portasm.asm has been replaced by a header file
3132 portasm.h. This includes a few assembler macro definitions.
3134 All saving and restoring of registers onto/off of the stack is now handled
3135 by the compiler. This means the initial stack setup for a task has to
3136 mimic the stack used by the compiler, which is different for debug and
3139 Slightly changed the operation of the demo application, details below.
3143 + portSWITCH_CONTEXT() replaced by vPortFirstContext().
3144 + pxPortInitialiseStack() modified to replicate the stack used by the
3146 + portasm.asm file removed.
3147 + portasm.h introduced. This contains macro definitions for
3148 portSWITCH_CONTEXT() and portFIRST_CONTEXT().
3149 + Context switch from ISR now uses the compiler generated interrupt
3150 mechanism. This is done simply by calling portSWITCH_CONTEXT and leaving
3151 the save/restore to compiler generated code.
3152 + Calls to taskYIELD() during ISR's have been replaced by calling the
3153 simpler and faster portSWITCH_CONTEXT().
3154 + The Flashlite 186 port now uses 186 instruction set (used to use 80x86
3156 + The blocking queue tasks within the demo application did not operate
3157 quite as described. This has been corrected.
3158 + The priority of the comtest Rx task within the demo application has been
3159 lowered. Received characters are now processed (read from the queue) at
3160 the idle priority, allowing low priority tasks to run evenly at times of
3161 a high communications overhead.
3162 + Prevent the call to kbhit() in main.c for debug builds as the debugger
3163 seems to have problems stepping over the call. This if for the PC port
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