CMSIS-RTOS  Version 1.03
Real-Time Operating System: API and RTX Reference Implementation.
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Using a CMSIS-RTOS Implementation

A CMSIS-RTOS implementation is typically provided as a library. To add the RTOS functionality to an existing CMSIS-based application, the RTOS library (and typically a configuration file) needs to be added. The available functionality of the RTOS library is defined in the header file cmsis_os.h that is specific for each CMSIS-RTOS implementation.

CMSIS_RTOS_Files.png
CMSIS-RTOS File Structure

Depending on the CMSIS-RTOS implementation, execution may start with the main function as the first thread. This has the benefit that an application programmer may use other middleware libraries that create threads internally, but the remaining part of the user application just uses the main thread. Therefore, the usage of the RTOS can be invisible to the application programmer, but libraries can use CMSIS-RTOS features.

Once the files are added to a project, the user can start working with the CMSIS-RTOS functions. A code example is provided below:

Code Example

#include "cmsis_os.h" // CMSIS-RTOS header file
void job1 (void const *argument) { // thread function 'job1'
while (1) {
: // execute some code
osDelay (10); // delay execution for 10 milliseconds
}
}
osThreadDef(job1, osPriorityAboveNormal, 1, 0); // define job1 as thread function
void job2 (void const *argument) { // thread function 'job2'
osThreadCreate(osThread(job1),NULL); // create job1 thread
while (1) {
: // execute some code
}
}
osThreadDef(job2, osPriorityNormal, 1, 0); // define job2 as thread function
void job3 (void const *argument) { // thread function 'job3'
while (1) {
: // execute some code
osDelay (20); // delay execution for 20 milliseconds
}
}
osThreadDef(job3, osPriorityNormal, 1, 0); // define job3 as thread function
int main (void) { // program execution starts here
osKernelInitialize (); // initialize RTOS kernel
: // setup and initialize peripherals
osThreadCreate (osThread(job2));
osThreadCreate (osThread(job3));
osKernelStart (); // start kernel with job2 execution
}

Header File Template: cmsis_os.h

The file cmsis_os.h is a template header file for a CMSIS-RTOS compliant Real-Time Operating System (RTOS). Each RTOS that is compliant with CMSIS-RTOS shall provide a specific cmsis_os.h header file that represents its implementation.

The file cmsis_os.h contains:

  • CMSIS-RTOS API function definitions
  • struct definitions for parameters and return types
  • status and priority values used by CMSIS-RTOS API functions
  • macros for defining threads and other kernel objects

Name conventions and header file modifications

All definitions are prefixed with os to give an unique name space for CMSIS-RTOS functions. Definitions that are prefixed os_ are not used in the application code but local to this header file. All definitions and functions that belong to a module are grouped and have a common prefix, i.e. osThread.

Definitions that are marked with CAN BE CHANGED can be adapted towards the needs of the actual CMSIS-RTOS implementation. These definitions can be specific to the underlying RTOS kernel.

Definitions that are marked with MUST REMAIN UNCHANGED cannot be altered. Otherwise the CMSIS-RTOS implementation is no longer compliant to the standard. Note that some functions are optional and need not to be provided by every CMSIS-RTOS implementation.

Define and reference object definitions

With #define osObjectsExternal objects are defined as external symbols. This allows to create a consistent header file that is used throughout a project as shown below:

Header File

#include <cmsis_os.h> // CMSIS RTOS header file
// Thread definition
extern void thread_sample (void const *argument); // function prototype
osThreadDef (thread_sample, osPriorityBelowNormal, 1, 100);
// Pool definition
osPoolDef(MyPool, 10, long);

This header file defines all objects when included in a C/C++ source file. When #define osObjectsExternal is present before the header file, the objects are defined as external symbols. A single consistent header file can therefore be used throughout the whole project.

Example

#include "osObjects.h" // Definition of the CMSIS-RTOS objects
#define osObjectsExternal // Objects will be defined as external symbols
#include "osObjects.h" // Reference to the CMSIS-RTOS objects

Header file cmsis_os.h

/* ----------------------------------------------------------------------
* $Date: 5. February 2013
* $Revision: V1.02
*
* Project: CMSIS-RTOS API
* Title: cmsis_os.h template header file
*
* Version 0.02
* Initial Proposal Phase
* Version 0.03
* osKernelStart added, optional feature: main started as thread
* osSemaphores have standard behavior
* osTimerCreate does not start the timer, added osTimerStart
* osThreadPass is renamed to osThreadYield
* Version 1.01
* Support for C++ interface
* - const attribute removed from the osXxxxDef_t typedef's
* - const attribute added to the osXxxxDef macros
* Added: osTimerDelete, osMutexDelete, osSemaphoreDelete
* Added: osKernelInitialize
* Version 1.02
* Control functions for short timeouts in microsecond resolution:
* Added: osKernelSysTick, osKernelSysTickFrequency, osKernelSysTickMicroSec
* Removed: osSignalGet
*----------------------------------------------------------------------------
*
* Copyright (c) 2013-2017 ARM LIMITED
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the License); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an AS IS BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*---------------------------------------------------------------------------*/
#ifndef _CMSIS_OS_H
#define _CMSIS_OS_H
/// \note MUST REMAIN UNCHANGED: \b osCMSIS identifies the CMSIS-RTOS API version.
#define osCMSIS 0x10002 ///< API version (main [31:16] .sub [15:0])
/// \note CAN BE CHANGED: \b osCMSIS_KERNEL identifies the underlying RTOS kernel and version number.
#define osCMSIS_KERNEL 0x10000 ///< RTOS identification and version (main [31:16] .sub [15:0])
/// \note MUST REMAIN UNCHANGED: \b osKernelSystemId shall be consistent in every CMSIS-RTOS.
#define osKernelSystemId "KERNEL V1.00" ///< RTOS identification string
/// \note MUST REMAIN UNCHANGED: \b osFeature_xxx shall be consistent in every CMSIS-RTOS.
#define osFeature_MainThread 1 ///< main thread 1=main can be thread, 0=not available
#define osFeature_Pool 1 ///< Memory Pools: 1=available, 0=not available
#define osFeature_MailQ 1 ///< Mail Queues: 1=available, 0=not available
#define osFeature_MessageQ 1 ///< Message Queues: 1=available, 0=not available
#define osFeature_Signals 8 ///< maximum number of Signal Flags available per thread
#define osFeature_Semaphore 30 ///< maximum count for \ref osSemaphoreCreate function
#define osFeature_Wait 1 ///< osWait function: 1=available, 0=not available
#define osFeature_SysTick 1 ///< osKernelSysTick functions: 1=available, 0=not available
#include <stdint.h>
#include <stddef.h>
#ifdef __cplusplus
extern "C"
{
#endif
// ==== Enumeration, structures, defines ====
/// Priority used for thread control.
/// \note MUST REMAIN UNCHANGED: \b osPriority shall be consistent in every CMSIS-RTOS.
typedef enum {
osPriorityIdle = -3, ///< priority: idle (lowest)
osPriorityLow = -2, ///< priority: low
osPriorityBelowNormal = -1, ///< priority: below normal
osPriorityNormal = 0, ///< priority: normal (default)
osPriorityAboveNormal = +1, ///< priority: above normal
osPriorityHigh = +2, ///< priority: high
osPriorityRealtime = +3, ///< priority: realtime (highest)
osPriorityError = 0x84 ///< system cannot determine priority or thread has illegal priority
} osPriority;
/// Timeout value.
/// \note MUST REMAIN UNCHANGED: \b osWaitForever shall be consistent in every CMSIS-RTOS.
#define osWaitForever 0xFFFFFFFF ///< wait forever timeout value
/// Status code values returned by CMSIS-RTOS functions.
/// \note MUST REMAIN UNCHANGED: \b osStatus shall be consistent in every CMSIS-RTOS.
typedef enum {
osOK = 0, ///< function completed; no error or event occurred.
osEventSignal = 0x08, ///< function completed; signal event occurred.
osEventMessage = 0x10, ///< function completed; message event occurred.
osEventMail = 0x20, ///< function completed; mail event occurred.
osEventTimeout = 0x40, ///< function completed; timeout occurred.
osErrorParameter = 0x80, ///< parameter error: a mandatory parameter was missing or specified an incorrect object.
osErrorResource = 0x81, ///< resource not available: a specified resource was not available.
osErrorTimeoutResource = 0xC1, ///< resource not available within given time: a specified resource was not available within the timeout period.
osErrorISR = 0x82, ///< not allowed in ISR context: the function cannot be called from interrupt service routines.
osErrorISRRecursive = 0x83, ///< function called multiple times from ISR with same object.
osErrorPriority = 0x84, ///< system cannot determine priority or thread has illegal priority.
osErrorNoMemory = 0x85, ///< system is out of memory: it was impossible to allocate or reserve memory for the operation.
osErrorValue = 0x86, ///< value of a parameter is out of range.
osErrorOS = 0xFF, ///< unspecified RTOS error: run-time error but no other error message fits.
os_status_reserved = 0x7FFFFFFF ///< prevent from enum down-size compiler optimization.
} osStatus;
/// Timer type value for the timer definition.
/// \note MUST REMAIN UNCHANGED: \b os_timer_type shall be consistent in every CMSIS-RTOS.
typedef enum {
osTimerOnce = 0, ///< one-shot timer
osTimerPeriodic = 1 ///< repeating timer
} os_timer_type;
/// Entry point of a thread.
/// \note MUST REMAIN UNCHANGED: \b os_pthread shall be consistent in every CMSIS-RTOS.
typedef void (*os_pthread) (void const *argument);
/// Entry point of a timer call back function.
/// \note MUST REMAIN UNCHANGED: \b os_ptimer shall be consistent in every CMSIS-RTOS.
typedef void (*os_ptimer) (void const *argument);
// >>> the following data type definitions may shall adapted towards a specific RTOS
/// Thread ID identifies the thread (pointer to a thread control block).
/// \note CAN BE CHANGED: \b os_thread_cb is implementation specific in every CMSIS-RTOS.
typedef struct os_thread_cb *osThreadId;
/// Timer ID identifies the timer (pointer to a timer control block).
/// \note CAN BE CHANGED: \b os_timer_cb is implementation specific in every CMSIS-RTOS.
typedef struct os_timer_cb *osTimerId;
/// Mutex ID identifies the mutex (pointer to a mutex control block).
/// \note CAN BE CHANGED: \b os_mutex_cb is implementation specific in every CMSIS-RTOS.
typedef struct os_mutex_cb *osMutexId;
/// Semaphore ID identifies the semaphore (pointer to a semaphore control block).
/// \note CAN BE CHANGED: \b os_semaphore_cb is implementation specific in every CMSIS-RTOS.
typedef struct os_semaphore_cb *osSemaphoreId;
/// Pool ID identifies the memory pool (pointer to a memory pool control block).
/// \note CAN BE CHANGED: \b os_pool_cb is implementation specific in every CMSIS-RTOS.
typedef struct os_pool_cb *osPoolId;
/// Message ID identifies the message queue (pointer to a message queue control block).
/// \note CAN BE CHANGED: \b os_messageQ_cb is implementation specific in every CMSIS-RTOS.
typedef struct os_messageQ_cb *osMessageQId;
/// Mail ID identifies the mail queue (pointer to a mail queue control block).
/// \note CAN BE CHANGED: \b os_mailQ_cb is implementation specific in every CMSIS-RTOS.
typedef struct os_mailQ_cb *osMailQId;
/// Thread Definition structure contains startup information of a thread.
/// \note CAN BE CHANGED: \b os_thread_def is implementation specific in every CMSIS-RTOS.
typedef struct os_thread_def {
os_pthread pthread; ///< start address of thread function
osPriority tpriority; ///< initial thread priority
uint32_t instances; ///< maximum number of instances of that thread function
uint32_t stacksize; ///< stack size requirements in bytes; 0 is default stack size
} osThreadDef_t;
/// Timer Definition structure contains timer parameters.
/// \note CAN BE CHANGED: \b os_timer_def is implementation specific in every CMSIS-RTOS.
typedef struct os_timer_def {
os_ptimer ptimer; ///< start address of a timer function
} osTimerDef_t;
/// Mutex Definition structure contains setup information for a mutex.
/// \note CAN BE CHANGED: \b os_mutex_def is implementation specific in every CMSIS-RTOS.
typedef struct os_mutex_def {
uint32_t dummy; ///< dummy value.
} osMutexDef_t;
/// Semaphore Definition structure contains setup information for a semaphore.
/// \note CAN BE CHANGED: \b os_semaphore_def is implementation specific in every CMSIS-RTOS.
typedef struct os_semaphore_def {
uint32_t dummy; ///< dummy value.
} osSemaphoreDef_t;
/// Definition structure for memory block allocation.
/// \note CAN BE CHANGED: \b os_pool_def is implementation specific in every CMSIS-RTOS.
typedef struct os_pool_def {
uint32_t pool_sz; ///< number of items (elements) in the pool
uint32_t item_sz; ///< size of an item
void *pool; ///< pointer to memory for pool
} osPoolDef_t;
/// Definition structure for message queue.
/// \note CAN BE CHANGED: \b os_messageQ_def is implementation specific in every CMSIS-RTOS.
typedef struct os_messageQ_def {
uint32_t queue_sz; ///< number of elements in the queue
uint32_t item_sz; ///< size of an item
void *pool; ///< memory array for messages
} osMessageQDef_t;
/// Definition structure for mail queue.
/// \note CAN BE CHANGED: \b os_mailQ_def is implementation specific in every CMSIS-RTOS.
typedef struct os_mailQ_def {
uint32_t queue_sz; ///< number of elements in the queue
uint32_t item_sz; ///< size of an item
void *pool; ///< memory array for mail
} osMailQDef_t;
/// Event structure contains detailed information about an event.
/// \note MUST REMAIN UNCHANGED: \b os_event shall be consistent in every CMSIS-RTOS.
/// However the struct may be extended at the end.
typedef struct {
osStatus status; ///< status code: event or error information
union {
uint32_t v; ///< message as 32-bit value
void *p; ///< message or mail as void pointer
int32_t signals; ///< signal flags
} value; ///< event value
union {
osMailQId mail_id; ///< mail id obtained by \ref osMailCreate
osMessageQId message_id; ///< message id obtained by \ref osMessageCreate
} def; ///< event definition
} osEvent;
// ==== Kernel Control Functions ====
/// Initialize the RTOS Kernel for creating objects.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osKernelInitialize shall be consistent in every CMSIS-RTOS.
osStatus osKernelInitialize (void);
/// Start the RTOS Kernel.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osKernelStart shall be consistent in every CMSIS-RTOS.
osStatus osKernelStart (void);
/// Check if the RTOS kernel is already started.
/// \note MUST REMAIN UNCHANGED: \b osKernelRunning shall be consistent in every CMSIS-RTOS.
/// \return 0 RTOS is not started, 1 RTOS is started.
int32_t osKernelRunning(void);
#if (defined (osFeature_SysTick) && (osFeature_SysTick != 0)) // System Timer available
/// Get the RTOS kernel system timer counter
/// \note MUST REMAIN UNCHANGED: \b osKernelSysTick shall be consistent in every CMSIS-RTOS.
/// \return RTOS kernel system timer as 32-bit value
uint32_t osKernelSysTick (void);
/// The RTOS kernel system timer frequency in Hz
/// \note Reflects the system timer setting and is typically defined in a configuration file.
#define osKernelSysTickFrequency 100000000
/// Convert a microseconds value to a RTOS kernel system timer value.
/// \param microsec time value in microseconds.
/// \return time value normalized to the \ref osKernelSysTickFrequency
#define osKernelSysTickMicroSec(microsec) (((uint64_t)microsec * (osKernelSysTickFrequency)) / 1000000)
#endif // System Timer available
// ==== Thread Management ====
/// Create a Thread Definition with function, priority, and stack requirements.
/// \param name name of the thread function.
/// \param priority initial priority of the thread function.
/// \param instances number of possible thread instances.
/// \param stacksz stack size (in bytes) requirements for the thread function.
/// \note CAN BE CHANGED: The parameters to \b osThreadDef shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#if defined (osObjectsExternal) // object is external
#define osThreadDef(name, priority, instances, stacksz) \
extern const osThreadDef_t os_thread_def_##name
#else // define the object
#define osThreadDef(name, priority, instances, stacksz) \
const osThreadDef_t os_thread_def_##name = \
{ (name), (priority), (instances), (stacksz) }
#endif
/// Access a Thread definition.
/// \param name name of the thread definition object.
/// \note CAN BE CHANGED: The parameter to \b osThread shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#define osThread(name) \
&os_thread_def_##name
/// Create a thread and add it to Active Threads and set it to state READY.
/// \param[in] thread_def thread definition referenced with \ref osThread.
/// \param[in] argument pointer that is passed to the thread function as start argument.
/// \return thread ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osThreadCreate shall be consistent in every CMSIS-RTOS.
osThreadId osThreadCreate (const osThreadDef_t *thread_def, void *argument);
/// Return the thread ID of the current running thread.
/// \return thread ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osThreadGetId shall be consistent in every CMSIS-RTOS.
osThreadId osThreadGetId (void);
/// Terminate execution of a thread and remove it from Active Threads.
/// \param[in] thread_id thread ID obtained by \ref osThreadCreate or \ref osThreadGetId.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osThreadTerminate shall be consistent in every CMSIS-RTOS.
osStatus osThreadTerminate (osThreadId thread_id);
/// Pass control to next thread that is in state \b READY.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osThreadYield shall be consistent in every CMSIS-RTOS.
osStatus osThreadYield (void);
/// Change priority of an active thread.
/// \param[in] thread_id thread ID obtained by \ref osThreadCreate or \ref osThreadGetId.
/// \param[in] priority new priority value for the thread function.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osThreadSetPriority shall be consistent in every CMSIS-RTOS.
osStatus osThreadSetPriority (osThreadId thread_id, osPriority priority);
/// Get current priority of an active thread.
/// \param[in] thread_id thread ID obtained by \ref osThreadCreate or \ref osThreadGetId.
/// \return current priority value of the thread function.
/// \note MUST REMAIN UNCHANGED: \b osThreadGetPriority shall be consistent in every CMSIS-RTOS.
osPriority osThreadGetPriority (osThreadId thread_id);
// ==== Generic Wait Functions ====
/// Wait for Timeout (Time Delay).
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue "time delay" value
/// \return status code that indicates the execution status of the function.
osStatus osDelay (uint32_t millisec);
#if (defined (osFeature_Wait) && (osFeature_Wait != 0)) // Generic Wait available
/// Wait for Signal, Message, Mail, or Timeout.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out
/// \return event that contains signal, message, or mail information or error code.
/// \note MUST REMAIN UNCHANGED: \b osWait shall be consistent in every CMSIS-RTOS.
osEvent osWait (uint32_t millisec);
#endif // Generic Wait available
// ==== Timer Management Functions ====
/// Define a Timer object.
/// \param name name of the timer object.
/// \param function name of the timer call back function.
/// \note CAN BE CHANGED: The parameter to \b osTimerDef shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#if defined (osObjectsExternal) // object is external
#define osTimerDef(name, function) \
extern const osTimerDef_t os_timer_def_##name
#else // define the object
#define osTimerDef(name, function) \
const osTimerDef_t os_timer_def_##name = \
{ (function) }
#endif
/// Access a Timer definition.
/// \param name name of the timer object.
/// \note CAN BE CHANGED: The parameter to \b osTimer shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#define osTimer(name) \
&os_timer_def_##name
/// Create a timer.
/// \param[in] timer_def timer object referenced with \ref osTimer.
/// \param[in] type osTimerOnce for one-shot or osTimerPeriodic for periodic behavior.
/// \param[in] argument argument to the timer call back function.
/// \return timer ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osTimerCreate shall be consistent in every CMSIS-RTOS.
osTimerId osTimerCreate (const osTimerDef_t *timer_def, os_timer_type type, void *argument);
/// Start or restart a timer.
/// \param[in] timer_id timer ID obtained by \ref osTimerCreate.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue "time delay" value of the timer.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osTimerStart shall be consistent in every CMSIS-RTOS.
osStatus osTimerStart (osTimerId timer_id, uint32_t millisec);
/// Stop the timer.
/// \param[in] timer_id timer ID obtained by \ref osTimerCreate.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osTimerStop shall be consistent in every CMSIS-RTOS.
osStatus osTimerStop (osTimerId timer_id);
/// Delete a timer that was created by \ref osTimerCreate.
/// \param[in] timer_id timer ID obtained by \ref osTimerCreate.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osTimerDelete shall be consistent in every CMSIS-RTOS.
osStatus osTimerDelete (osTimerId timer_id);
// ==== Signal Management ====
/// Set the specified Signal Flags of an active thread.
/// \param[in] thread_id thread ID obtained by \ref osThreadCreate or \ref osThreadGetId.
/// \param[in] signals specifies the signal flags of the thread that should be set.
/// \return previous signal flags of the specified thread or 0x80000000 in case of incorrect parameters.
/// \note MUST REMAIN UNCHANGED: \b osSignalSet shall be consistent in every CMSIS-RTOS.
int32_t osSignalSet (osThreadId thread_id, int32_t signals);
/// Clear the specified Signal Flags of an active thread.
/// \param[in] thread_id thread ID obtained by \ref osThreadCreate or \ref osThreadGetId.
/// \param[in] signals specifies the signal flags of the thread that shall be cleared.
/// \return previous signal flags of the specified thread or 0x80000000 in case of incorrect parameters or call from ISR.
/// \note MUST REMAIN UNCHANGED: \b osSignalClear shall be consistent in every CMSIS-RTOS.
int32_t osSignalClear (osThreadId thread_id, int32_t signals);
/// Wait for one or more Signal Flags to become signaled for the current \b RUNNING thread.
/// \param[in] signals wait until all specified signal flags set or 0 for any single signal flag.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out.
/// \return event flag information or error code.
/// \note MUST REMAIN UNCHANGED: \b osSignalWait shall be consistent in every CMSIS-RTOS.
osEvent osSignalWait (int32_t signals, uint32_t millisec);
// ==== Mutex Management ====
/// Define a Mutex.
/// \param name name of the mutex object.
/// \note CAN BE CHANGED: The parameter to \b osMutexDef shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#if defined (osObjectsExternal) // object is external
#define osMutexDef(name) \
extern const osMutexDef_t os_mutex_def_##name
#else // define the object
#define osMutexDef(name) \
const osMutexDef_t os_mutex_def_##name = { 0 }
#endif
/// Access a Mutex definition.
/// \param name name of the mutex object.
/// \note CAN BE CHANGED: The parameter to \b osMutex shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#define osMutex(name) \
&os_mutex_def_##name
/// Create and Initialize a Mutex object.
/// \param[in] mutex_def mutex definition referenced with \ref osMutex.
/// \return mutex ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osMutexCreate shall be consistent in every CMSIS-RTOS.
osMutexId osMutexCreate (const osMutexDef_t *mutex_def);
/// Wait until a Mutex becomes available.
/// \param[in] mutex_id mutex ID obtained by \ref osMutexCreate.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osMutexWait shall be consistent in every CMSIS-RTOS.
osStatus osMutexWait (osMutexId mutex_id, uint32_t millisec);
/// Release a Mutex that was obtained by \ref osMutexWait.
/// \param[in] mutex_id mutex ID obtained by \ref osMutexCreate.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osMutexRelease shall be consistent in every CMSIS-RTOS.
osStatus osMutexRelease (osMutexId mutex_id);
/// Delete a Mutex that was created by \ref osMutexCreate.
/// \param[in] mutex_id mutex ID obtained by \ref osMutexCreate.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osMutexDelete shall be consistent in every CMSIS-RTOS.
osStatus osMutexDelete (osMutexId mutex_id);
// ==== Semaphore Management Functions ====
#if (defined (osFeature_Semaphore) && (osFeature_Semaphore != 0)) // Semaphore available
/// Define a Semaphore object.
/// \param name name of the semaphore object.
/// \note CAN BE CHANGED: The parameter to \b osSemaphoreDef shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#if defined (osObjectsExternal) // object is external
#define osSemaphoreDef(name) \
extern const osSemaphoreDef_t os_semaphore_def_##name
#else // define the object
#define osSemaphoreDef(name) \
const osSemaphoreDef_t os_semaphore_def_##name = { 0 }
#endif
/// Access a Semaphore definition.
/// \param name name of the semaphore object.
/// \note CAN BE CHANGED: The parameter to \b osSemaphore shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#define osSemaphore(name) \
&os_semaphore_def_##name
/// Create and Initialize a Semaphore object used for managing resources.
/// \param[in] semaphore_def semaphore definition referenced with \ref osSemaphore.
/// \param[in] count number of available resources.
/// \return semaphore ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osSemaphoreCreate shall be consistent in every CMSIS-RTOS.
osSemaphoreId osSemaphoreCreate (const osSemaphoreDef_t *semaphore_def, int32_t count);
/// Wait until a Semaphore token becomes available.
/// \param[in] semaphore_id semaphore object referenced with \ref osSemaphoreCreate.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out.
/// \return number of available tokens, or -1 in case of incorrect parameters.
/// \note MUST REMAIN UNCHANGED: \b osSemaphoreWait shall be consistent in every CMSIS-RTOS.
int32_t osSemaphoreWait (osSemaphoreId semaphore_id, uint32_t millisec);
/// Release a Semaphore token.
/// \param[in] semaphore_id semaphore object referenced with \ref osSemaphoreCreate.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osSemaphoreRelease shall be consistent in every CMSIS-RTOS.
osStatus osSemaphoreRelease (osSemaphoreId semaphore_id);
/// Delete a Semaphore that was created by \ref osSemaphoreCreate.
/// \param[in] semaphore_id semaphore object referenced with \ref osSemaphoreCreate.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osSemaphoreDelete shall be consistent in every CMSIS-RTOS.
osStatus osSemaphoreDelete (osSemaphoreId semaphore_id);
#endif // Semaphore available
// ==== Memory Pool Management Functions ====
#if (defined (osFeature_Pool) && (osFeature_Pool != 0)) // Memory Pool Management available
/// \brief Define a Memory Pool.
/// \param name name of the memory pool.
/// \param no maximum number of blocks (objects) in the memory pool.
/// \param type data type of a single block (object).
/// \note CAN BE CHANGED: The parameter to \b osPoolDef shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#if defined (osObjectsExternal) // object is external
#define osPoolDef(name, no, type) \
extern const osPoolDef_t os_pool_def_##name
#else // define the object
#define osPoolDef(name, no, type) \
const osPoolDef_t os_pool_def_##name = \
{ (no), sizeof(type), NULL }
#endif
/// \brief Access a Memory Pool definition.
/// \param name name of the memory pool
/// \note CAN BE CHANGED: The parameter to \b osPool shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#define osPool(name) \
&os_pool_def_##name
/// Create and Initialize a memory pool.
/// \param[in] pool_def memory pool definition referenced with \ref osPool.
/// \return memory pool ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osPoolCreate shall be consistent in every CMSIS-RTOS.
osPoolId osPoolCreate (const osPoolDef_t *pool_def);
/// Allocate a memory block from a memory pool.
/// \param[in] pool_id memory pool ID obtain referenced with \ref osPoolCreate.
/// \return address of the allocated memory block or NULL in case of no memory available.
/// \note MUST REMAIN UNCHANGED: \b osPoolAlloc shall be consistent in every CMSIS-RTOS.
void *osPoolAlloc (osPoolId pool_id);
/// Allocate a memory block from a memory pool and set memory block to zero.
/// \param[in] pool_id memory pool ID obtain referenced with \ref osPoolCreate.
/// \return address of the allocated memory block or NULL in case of no memory available.
/// \note MUST REMAIN UNCHANGED: \b osPoolCAlloc shall be consistent in every CMSIS-RTOS.
void *osPoolCAlloc (osPoolId pool_id);
/// Return an allocated memory block back to a specific memory pool.
/// \param[in] pool_id memory pool ID obtain referenced with \ref osPoolCreate.
/// \param[in] block address of the allocated memory block that is returned to the memory pool.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osPoolFree shall be consistent in every CMSIS-RTOS.
osStatus osPoolFree (osPoolId pool_id, void *block);
#endif // Memory Pool Management available
// ==== Message Queue Management Functions ====
#if (defined (osFeature_MessageQ) && (osFeature_MessageQ != 0)) // Message Queues available
/// \brief Create a Message Queue Definition.
/// \param name name of the queue.
/// \param queue_sz maximum number of messages in the queue.
/// \param type data type of a single message element (for debugger).
/// \note CAN BE CHANGED: The parameter to \b osMessageQDef shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#if defined (osObjectsExternal) // object is external
#define osMessageQDef(name, queue_sz, type) \
extern const osMessageQDef_t os_messageQ_def_##name
#else // define the object
#define osMessageQDef(name, queue_sz, type) \
const osMessageQDef_t os_messageQ_def_##name = \
{ (queue_sz), sizeof (type) }
#endif
/// \brief Access a Message Queue Definition.
/// \param name name of the queue
/// \note CAN BE CHANGED: The parameter to \b osMessageQ shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#define osMessageQ(name) \
&os_messageQ_def_##name
/// Create and Initialize a Message Queue.
/// \param[in] queue_def queue definition referenced with \ref osMessageQ.
/// \param[in] thread_id thread ID (obtained by \ref osThreadCreate or \ref osThreadGetId) or NULL.
/// \return message queue ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osMessageCreate shall be consistent in every CMSIS-RTOS.
osMessageQId osMessageCreate (const osMessageQDef_t *queue_def, osThreadId thread_id);
/// Put a Message to a Queue.
/// \param[in] queue_id message queue ID obtained with \ref osMessageCreate.
/// \param[in] info message information.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osMessagePut shall be consistent in every CMSIS-RTOS.
osStatus osMessagePut (osMessageQId queue_id, uint32_t info, uint32_t millisec);
/// Get a Message or Wait for a Message from a Queue.
/// \param[in] queue_id message queue ID obtained with \ref osMessageCreate.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out.
/// \return event information that includes status code.
/// \note MUST REMAIN UNCHANGED: \b osMessageGet shall be consistent in every CMSIS-RTOS.
osEvent osMessageGet (osMessageQId queue_id, uint32_t millisec);
#endif // Message Queues available
// ==== Mail Queue Management Functions ====
#if (defined (osFeature_MailQ) && (osFeature_MailQ != 0)) // Mail Queues available
/// \brief Create a Mail Queue Definition.
/// \param name name of the queue
/// \param queue_sz maximum number of messages in queue
/// \param type data type of a single message element
/// \note CAN BE CHANGED: The parameter to \b osMailQDef shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#if defined (osObjectsExternal) // object is external
#define osMailQDef(name, queue_sz, type) \
extern const osMailQDef_t os_mailQ_def_##name
#else // define the object
#define osMailQDef(name, queue_sz, type) \
const osMailQDef_t os_mailQ_def_##name = \
{ (queue_sz), sizeof (type) }
#endif
/// \brief Access a Mail Queue Definition.
/// \param name name of the queue
/// \note CAN BE CHANGED: The parameter to \b osMailQ shall be consistent but the
/// macro body is implementation specific in every CMSIS-RTOS.
#define osMailQ(name) \
&os_mailQ_def_##name
/// Create and Initialize mail queue.
/// \param[in] queue_def reference to the mail queue definition obtain with \ref osMailQ
/// \param[in] thread_id thread ID (obtained by \ref osThreadCreate or \ref osThreadGetId) or NULL.
/// \return mail queue ID for reference by other functions or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osMailCreate shall be consistent in every CMSIS-RTOS.
osMailQId osMailCreate (const osMailQDef_t *queue_def, osThreadId thread_id);
/// Allocate a memory block from a mail.
/// \param[in] queue_id mail queue ID obtained with \ref osMailCreate.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out
/// \return pointer to memory block that can be filled with mail or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osMailAlloc shall be consistent in every CMSIS-RTOS.
void *osMailAlloc (osMailQId queue_id, uint32_t millisec);
/// Allocate a memory block from a mail and set memory block to zero.
/// \param[in] queue_id mail queue ID obtained with \ref osMailCreate.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out
/// \return pointer to memory block that can be filled with mail or NULL in case of error.
/// \note MUST REMAIN UNCHANGED: \b osMailCAlloc shall be consistent in every CMSIS-RTOS.
void *osMailCAlloc (osMailQId queue_id, uint32_t millisec);
/// Put a mail to a queue.
/// \param[in] queue_id mail queue ID obtained with \ref osMailCreate.
/// \param[in] mail memory block previously allocated with \ref osMailAlloc or \ref osMailCAlloc.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osMailPut shall be consistent in every CMSIS-RTOS.
osStatus osMailPut (osMailQId queue_id, void *mail);
/// Get a mail from a queue.
/// \param[in] queue_id mail queue ID obtained with \ref osMailCreate.
/// \param[in] millisec \ref CMSIS_RTOS_TimeOutValue or 0 in case of no time-out
/// \return event that contains mail information or error code.
/// \note MUST REMAIN UNCHANGED: \b osMailGet shall be consistent in every CMSIS-RTOS.
osEvent osMailGet (osMailQId queue_id, uint32_t millisec);
/// Free a memory block from a mail.
/// \param[in] queue_id mail queue ID obtained with \ref osMailCreate.
/// \param[in] mail pointer to the memory block that was obtained with \ref osMailGet.
/// \return status code that indicates the execution status of the function.
/// \note MUST REMAIN UNCHANGED: \b osMailFree shall be consistent in every CMSIS-RTOS.
osStatus osMailFree (osMailQId queue_id, void *mail);
#endif // Mail Queues available
#ifdef __cplusplus
}
#endif
#endif // _CMSIS_OS_H