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class="SelectionMark"> </span>Pages</a></div> <!-- iframe showing the search results (closed by default) --> <div id="MSearchResultsWindow"> <iframe src="javascript:void(0)" frameborder="0" name="MSearchResults" id="MSearchResults"> </iframe> </div> <div class="header"> <div class="summary"> <a href="#define-members">Macros</a> | <a href="#func-members">Functions</a> </div> <div class="headertitle"> <div class="title">Message Queue<div class="ingroups"><a class="el" href="group__CMSIS__RTOS__InterThread.html">Inter-Thread Communication and Resource Sharing</a></div></div> </div> </div><!--header--> <div class="contents"> <p>Exchange messages between threads in a FIFO-like operation. <a href="#details">More...</a></p> <table class="memberdecls"> <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="define-members"></a> Macros</h2></td></tr> <tr class="memitem:ga479a6561f859e3d4818e25708593d203"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#ga479a6561f859e3d4818e25708593d203">osFeature_MessageQ</a>   1</td></tr> <tr class="memdesc:ga479a6561f859e3d4818e25708593d203"><td class="mdescLeft"> </td><td class="mdescRight">Message Queues: 1=available, 0=not available. <a href="#ga479a6561f859e3d4818e25708593d203">More...</a><br/></td></tr> <tr class="separator:ga479a6561f859e3d4818e25708593d203"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:gac9a6a6276c12609793e7701afcc82326"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gac9a6a6276c12609793e7701afcc82326">osMessageQDef</a>(name, queue_sz, type)</td></tr> <tr class="memdesc:gac9a6a6276c12609793e7701afcc82326"><td class="mdescLeft"> </td><td class="mdescRight">Create a Message Queue Definition. <a href="#gac9a6a6276c12609793e7701afcc82326">More...</a><br/></td></tr> <tr class="separator:gac9a6a6276c12609793e7701afcc82326"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:ga2d446a0b4bb90bf05d6f92eedeaabc97"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#ga2d446a0b4bb90bf05d6f92eedeaabc97">osMessageQ</a>(name)   &os_messageQ_def_##name</td></tr> <tr class="memdesc:ga2d446a0b4bb90bf05d6f92eedeaabc97"><td class="mdescLeft"> </td><td class="mdescRight">Access a Message Queue Definition. <a href="#ga2d446a0b4bb90bf05d6f92eedeaabc97">More...</a><br/></td></tr> <tr class="separator:ga2d446a0b4bb90bf05d6f92eedeaabc97"><td class="memSeparator" colspan="2"> </td></tr> </table><table class="memberdecls"> <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="func-members"></a> Functions</h2></td></tr> <tr class="memitem:gaf3b9345cf426304d46565152bc26fb78"><td class="memItemLeft" align="right" valign="top"><a class="el" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gaf3b9345cf426304d46565152bc26fb78">osMessageCreate</a> (const <a class="el" href="structosMessageQDef__t.html">osMessageQDef_t</a> *queue_def, <a class="el" href="cmsis__os_8h.html#adfeb153a84a81309e2d958268197617f">osThreadId</a> thread_id)</td></tr> <tr class="memdesc:gaf3b9345cf426304d46565152bc26fb78"><td class="mdescLeft"> </td><td class="mdescRight">Create and Initialize a Message Queue. <a href="#gaf3b9345cf426304d46565152bc26fb78">More...</a><br/></td></tr> <tr class="separator:gaf3b9345cf426304d46565152bc26fb78"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:gac0dcf462fc92de8ffaba6cc004514a6d"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__CMSIS__RTOS__Status.html#gae2e091fefc4c767117727bd5aba4d99e">osStatus</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gac0dcf462fc92de8ffaba6cc004514a6d">osMessagePut</a> (<a class="el" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> queue_id, uint32_t info, uint32_t millisec)</td></tr> <tr class="memdesc:gac0dcf462fc92de8ffaba6cc004514a6d"><td class="mdescLeft"> </td><td class="mdescRight">Put a Message to a Queue. <a href="#gac0dcf462fc92de8ffaba6cc004514a6d">More...</a><br/></td></tr> <tr class="separator:gac0dcf462fc92de8ffaba6cc004514a6d"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:ga6c6892b8f2296cca6becd57ca2d7e1ae"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__CMSIS__RTOS__Definitions.html#structosEvent">osEvent</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#ga6c6892b8f2296cca6becd57ca2d7e1ae">osMessageGet</a> (<a class="el" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> queue_id, uint32_t millisec)</td></tr> <tr class="memdesc:ga6c6892b8f2296cca6becd57ca2d7e1ae"><td class="mdescLeft"> </td><td class="mdescRight">Get a Message or Wait for a Message from a Queue. <a href="#ga6c6892b8f2296cca6becd57ca2d7e1ae">More...</a><br/></td></tr> <tr class="separator:ga6c6892b8f2296cca6becd57ca2d7e1ae"><td class="memSeparator" colspan="2"> </td></tr> </table> <a name="details" id="details"></a><h2 class="groupheader">Description</h2> <p><b>Message</b> <b>passing</b> is another basic communication model between threads. In the message passing model, one thread sends data explicitly, while another thread receives it. The operation is more like some kind of I/O rather than a direct access to information to be shared. In CMSIS-RTOS, this mechanism is called s <b>message</b> <b>queue</b>. The data is passed from one thread to another in a FIFO-like operation. Using message queue functions, you can control, send, receive, or wait for messages. The data to be passed can be of integer or pointer type:</p> <div class="image"> <img src="MessageQueue.png" alt="MessageQueue.png"/> <div class="caption"> CMSIS-RTOS Message Queue</div></div> <p> Compared to a <a class="el" href="group__CMSIS__RTOS__PoolMgmt.html">Memory Pool</a>, message queues are less efficient in general, but solve a broader range of problems. Sometimes, threads do not have a common address space or the use of shared memory raises problems, such as mutual exclusion.</p> <h2>Working with Message Queues </h2> <p>Follow these steps to create and use a message queue:</p> <ol type="1"> <li>Setup the message queue: <div class="fragment"><div class="line"><a class="code" href="group__CMSIS__RTOS__Message.html#gac9a6a6276c12609793e7701afcc82326">osMessageQDef</a>(message_q, 5, uint32_t); <span class="comment">// Declare a message queue</span></div> <div class="line"><a class="code" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> (message_q_id); <span class="comment">// Declare an ID for the message queue</span></div> </div><!-- fragment --></li> <li>Then, create the message queue in a thread: <div class="fragment"><div class="line">message_q_id = <a class="code" href="group__CMSIS__RTOS__Message.html#gaf3b9345cf426304d46565152bc26fb78">osMessageCreate</a>(<a class="code" href="group__CMSIS__RTOS__Message.html#ga2d446a0b4bb90bf05d6f92eedeaabc97">osMessageQ</a>(message_q), NULL);</div> </div><!-- fragment --></li> <li>Fill the message queue with data: <div class="fragment"><div class="line">uint32_t data = 512;</div> <div class="line"> </div> <div class="line"><a class="code" href="group__CMSIS__RTOS__Mail.html#ga485ef6f81854ebda8ffbce4832181e02">osMailPut</a>(message_q_id, data, <a class="code" href="cmsis__os_8h.html#a9eb9a7a797a42e4b55eb171ecc609ddb">osWaitForever</a>);</div> </div><!-- fragment --></li> <li>From the receiving thread access the data using: <div class="fragment"><div class="line"><a class="code" href="group__CMSIS__RTOS__Definitions.html#structosEvent">osEvent</a> <span class="keyword">event</span> = <a class="code" href="group__CMSIS__RTOS__Message.html#ga6c6892b8f2296cca6becd57ca2d7e1ae">osMessageGet</a>(message_q_id, <a class="code" href="cmsis__os_8h.html#a9eb9a7a797a42e4b55eb171ecc609ddb">osWaitForever</a>);</div> </div><!-- fragment --> </li> </ol> <h2 class="groupheader">Macro Definition Documentation</h2> <a class="anchor" id="ga479a6561f859e3d4818e25708593d203"></a> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define osFeature_MessageQ   1</td> </tr> </table> </div><div class="memdoc"> <p>A CMSIS-RTOS implementation may support message queues.</p> <ul> <li>When <a class="el" href="group__CMSIS__RTOS__Mail.html#gaceb2e0071ce160d153047f2eac1aca8e">osFeature_MailQ</a> is 1 message queues are supported.</li> <li>When <a class="el" href="group__CMSIS__RTOS__Mail.html#gaceb2e0071ce160d153047f2eac1aca8e">osFeature_MailQ</a> is 0 no message queues are supported.</li> </ul> <p><a class="el" href="rtxImplementation.html">CMSIS-RTOS RTX</a> Setting: <b>osFeature_MessageQ</b> is 1 </p> </div> </div> <a class="anchor" id="ga2d446a0b4bb90bf05d6f92eedeaabc97"></a> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define osMessageQ</td> <td>(</td> <td class="paramtype"> </td> <td class="paramname">name</td><td>)</td> <td>   &os_messageQ_def_##name</td> </tr> </table> </div><div class="memdoc"> <p>Access to the message queue definition for the function <a class="el" href="group__CMSIS__RTOS__Message.html#gaf3b9345cf426304d46565152bc26fb78">osMessageCreate</a>.</p> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">name</td><td>name of the queue </td></tr> </table> </dd> </dl> <dl class="section note"><dt>Note</dt><dd>CAN BE CHANGED: The parameter to <b>osMessageQ</b> shall be consistent but the macro body is implementation specific in every CMSIS-RTOS. </dd></dl> </div> </div> <a class="anchor" id="gac9a6a6276c12609793e7701afcc82326"></a> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define osMessageQDef</td> <td>(</td> <td class="paramtype"> </td> <td class="paramname">name, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"> </td> <td class="paramname">queue_sz, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"> </td> <td class="paramname">type </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>Define the attributes of a message queue created by the function <a class="el" href="group__CMSIS__RTOS__Message.html#gaf3b9345cf426304d46565152bc26fb78">osMessageCreate</a> using <a class="el" href="group__CMSIS__RTOS__Message.html#ga2d446a0b4bb90bf05d6f92eedeaabc97">osMessageQ</a>.</p> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">name</td><td>name of the queue. </td></tr> <tr><td class="paramname">queue_sz</td><td>maximum number of messages in the queue. </td></tr> <tr><td class="paramname">type</td><td>data type of a single message element (for debugger). </td></tr> </table> </dd> </dl> <dl class="section note"><dt>Note</dt><dd>CAN BE CHANGED: The parameter to <b>osMessageQDef</b> shall be consistent but the macro body is implementation specific in every CMSIS-RTOS. </dd></dl> </div> </div> <h2 class="groupheader">Function Documentation</h2> <a class="anchor" id="gaf3b9345cf426304d46565152bc26fb78"></a> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname"><a class="el" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> osMessageCreate </td> <td>(</td> <td class="paramtype">const <a class="el" href="structosMessageQDef__t.html">osMessageQDef_t</a> * </td> <td class="paramname"><em>queue_def</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="cmsis__os_8h.html#adfeb153a84a81309e2d958268197617f">osThreadId</a> </td> <td class="paramname"><em>thread_id</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramdir">[in]</td><td class="paramname">queue_def</td><td>queue definition referenced with <a class="el" href="group__CMSIS__RTOS__Message.html#ga2d446a0b4bb90bf05d6f92eedeaabc97">osMessageQ</a>. </td></tr> <tr><td class="paramdir">[in]</td><td class="paramname">thread_id</td><td>thread ID (obtained by <a class="el" href="group__CMSIS__RTOS__ThreadMgmt.html#gac59b5713cb083702dce759c73fd90dff">osThreadCreate</a> or <a class="el" href="group__CMSIS__RTOS__ThreadMgmt.html#gab1df2a28925862ef8f9cf4e1c995c5a7">osThreadGetId</a>) or NULL. </td></tr> </table> </dd> </dl> <dl class="section return"><dt>Returns</dt><dd>message queue ID for reference by other functions or NULL in case of error. </dd></dl> <dl class="section note"><dt>Note</dt><dd>MUST REMAIN UNCHANGED: <b>osMessageCreate</b> shall be consistent in every CMSIS-RTOS.</dd></dl> <p>Create and initialize a message queue. The parameter <em>thread_id</em> registers the receiving thread for a message and is needed for the general <a class="el" href="technicalData.html#osWait">osWait</a> function to deliver the message.</p> <dl class="section note"><dt>Note</dt><dd>Cannot be called from <a class="el" href="functionOverview.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>.</dd></dl> <p><b>Code Example</b> </p> <div class="fragment"><div class="line"><span class="preprocessor">#include "<a class="code" href="cmsis__os_8h.html">cmsis_os.h</a>"</span></div> <div class="line"> </div> <div class="line"><a class="code" href="cmsis__os_8h.html#adfeb153a84a81309e2d958268197617f">osThreadId</a> tid_thread1; <span class="comment">// ID for thread 1</span></div> <div class="line"><a class="code" href="cmsis__os_8h.html#adfeb153a84a81309e2d958268197617f">osThreadId</a> tid_thread2; <span class="comment">// for thread 2</span></div> <div class="line"> </div> <div class="line"><span class="keyword">typedef</span> <span class="keyword">struct </span>{ <span class="comment">// Message object structure</span></div> <div class="line"> <span class="keywordtype">float</span> voltage; <span class="comment">// AD result of measured voltage</span></div> <div class="line"> <span class="keywordtype">float</span> current; <span class="comment">// AD result of measured current</span></div> <div class="line"> <span class="keywordtype">int</span> counter; <span class="comment">// A counter value</span></div> <div class="line">} T_MEAS;</div> <div class="line"> </div> <div class="line"><a class="code" href="group__CMSIS__RTOS__PoolMgmt.html#ga87b471d4fe2d5dbd0040708edd52771b">osPoolDef</a>(mpool, 16, T_MEAS); <span class="comment">// Define memory pool</span></div> <div class="line"><a class="code" href="cmsis__os_8h.html#a08d2e20fd9bbd96220fe068d420f3686">osPoolId</a> mpool;</div> <div class="line"><a class="code" href="group__CMSIS__RTOS__Message.html#gac9a6a6276c12609793e7701afcc82326">osMessageQDef</a>(MsgBox, 16, &T_MEAS); <span class="comment">// Define message queue</span></div> <div class="line"><a class="code" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> MsgBox;</div> <div class="line"> </div> <div class="line"><span class="keywordtype">void</span> send_thread (<span class="keywordtype">void</span> <span class="keyword">const</span> *argument); <span class="comment">// forward reference</span></div> <div class="line"><span class="keywordtype">void</span> recv_thread (<span class="keywordtype">void</span> <span class="keyword">const</span> *argument); <span class="comment">// forward reference</span></div> <div class="line"> <span class="comment">// Thread definitions</span></div> <div class="line"><a class="code" href="group__CMSIS__RTOS__ThreadMgmt.html#gaee93d929beb350f16e5cc7fa602e229f">osThreadDef</a>(send_thread, <a class="code" href="cmsis__os_8h.html#ga7f2b42f1983b9107775ec2a1c69a849aa45a2895ad30c79fb97de18cac7cc19f1">osPriorityNormal</a>, 1, 0);</div> <div class="line"><a class="code" href="group__CMSIS__RTOS__ThreadMgmt.html#gaee93d929beb350f16e5cc7fa602e229f">osThreadDef</a>(recv_thread, <a class="code" href="cmsis__os_8h.html#ga7f2b42f1983b9107775ec2a1c69a849aa45a2895ad30c79fb97de18cac7cc19f1">osPriorityNormal</a>, 1, 2000);</div> <div class="line"> </div> <div class="line"><span class="comment">//</span></div> <div class="line"><span class="comment">// Thread 1: Send thread</span></div> <div class="line"><span class="comment">//</span></div> <div class="line"><span class="keywordtype">void</span> send_thread (<span class="keywordtype">void</span> <span class="keyword">const</span> *argument) {</div> <div class="line"> T_MEAS *mptr;</div> <div class="line"> </div> <div class="line"> mptr = <a class="code" href="group__CMSIS__RTOS__PoolMgmt.html#gaa0b2994f1a866c19e0d11e6e0d44f543">osPoolAlloc</a>(mpool); <span class="comment">// Allocate memory for the message</span></div> <div class="line"> mptr->voltage = 223.72; <span class="comment">// Set the message content</span></div> <div class="line"> mptr->current = 17.54;</div> <div class="line"> mptr->counter = 120786;</div> <div class="line"> <a class="code" href="group__CMSIS__RTOS__Message.html#gac0dcf462fc92de8ffaba6cc004514a6d">osMessagePut</a>(MsgBox, (uint32_t)mptr, <a class="code" href="cmsis__os_8h.html#a9eb9a7a797a42e4b55eb171ecc609ddb">osWaitForever</a>); <span class="comment">// Send Message</span></div> <div class="line"> <a class="code" href="group__CMSIS__RTOS__Wait.html#ga02e19d5e723bfb06ba9324d625162255">osDelay</a>(100);</div> <div class="line"> </div> <div class="line"> mptr = <a class="code" href="group__CMSIS__RTOS__PoolMgmt.html#gaa0b2994f1a866c19e0d11e6e0d44f543">osPoolAlloc</a>(mpool); <span class="comment">// Allocate memory for the message</span></div> <div class="line"> mptr->voltage = 227.23; <span class="comment">// Prepare a 2nd message</span></div> <div class="line"> mptr->current = 12.41;</div> <div class="line"> mptr->counter = 170823;</div> <div class="line"> <a class="code" href="group__CMSIS__RTOS__Message.html#gac0dcf462fc92de8ffaba6cc004514a6d">osMessagePut</a>(MsgBox, (uint32_t)mptr, <a class="code" href="cmsis__os_8h.html#a9eb9a7a797a42e4b55eb171ecc609ddb">osWaitForever</a>); <span class="comment">// Send Message</span></div> <div class="line"> <a class="code" href="group__CMSIS__RTOS__ThreadMgmt.html#gaf13a667493c5d629a90c13e113b99233">osThreadYield</a>(); <span class="comment">// Cooperative multitasking</span></div> <div class="line"> <span class="comment">// We are done here, exit this thread</span></div> <div class="line">}</div> <div class="line"> </div> <div class="line"><span class="comment">//</span></div> <div class="line"><span class="comment">// Thread 2: Receive thread</span></div> <div class="line"><span class="comment">//</span></div> <div class="line"><span class="keywordtype">void</span> recv_thread (<span class="keywordtype">void</span> <span class="keyword">const</span> *argument) {</div> <div class="line"> T_MEAS *rptr;</div> <div class="line"> <a class="code" href="group__CMSIS__RTOS__Definitions.html#structosEvent">osEvent</a> evt;</div> <div class="line"> </div> <div class="line"> <span class="keywordflow">for</span> (;;) {</div> <div class="line"> evt = <a class="code" href="group__CMSIS__RTOS__Message.html#ga6c6892b8f2296cca6becd57ca2d7e1ae">osMessageGet</a>(MsgBox, <a class="code" href="cmsis__os_8h.html#a9eb9a7a797a42e4b55eb171ecc609ddb">osWaitForever</a>); <span class="comment">// wait for message</span></div> <div class="line"> <span class="keywordflow">if</span> (evt.<a class="code" href="group__CMSIS__RTOS__Definitions.html#ad477a289f1f03ac45407b64268d707d3">status</a> == <a class="code" href="group__CMSIS__RTOS__Status.html#gae2e091fefc4c767117727bd5aba4d99ead604f3673359dd4ac643b16dc5a2c342">osEventMessage</a>) {</div> <div class="line"> rptr = evt.<a class="code" href="group__CMSIS__RTOS__Definitions.html#a0b9f8fd3645f01d8cb09cae82add2d7f">value</a>.<a class="code" href="group__CMSIS__RTOS__Definitions.html#a117104b82864d3b23ec174af6d392709">p</a>;</div> <div class="line"> printf (<span class="stringliteral">"\nVoltage: %.2f V\n"</span>, rptr->voltage);</div> <div class="line"> printf (<span class="stringliteral">"Current: %.2f A\n"</span>, rptr->current);</div> <div class="line"> printf (<span class="stringliteral">"Number of cycles: %d\n"</span>, rptr->counter);</div> <div class="line"> <a class="code" href="group__CMSIS__RTOS__PoolMgmt.html#ga4a861e9c469c9d0daf5721bf174f8e54">osPoolFree</a>(mpool, rptr); <span class="comment">// free memory allocated for message</span></div> <div class="line"> }</div> <div class="line"> }</div> <div class="line">}</div> <div class="line"> </div> <div class="line"><span class="keywordtype">void</span> StartApplication (<span class="keywordtype">void</span>) {</div> <div class="line"> mpool = <a class="code" href="group__CMSIS__RTOS__PoolMgmt.html#ga34af5c4f4ab38f4138ea7f1f9ece3a1a">osPoolCreate</a>(<a class="code" href="group__CMSIS__RTOS__PoolMgmt.html#ga5f0b204a82327533d420210125c90697">osPool</a>(mpool)); <span class="comment">// create memory pool</span></div> <div class="line"> MsgBox = <a class="code" href="group__CMSIS__RTOS__Message.html#gaf3b9345cf426304d46565152bc26fb78">osMessageCreate</a>(<a class="code" href="group__CMSIS__RTOS__Message.html#ga2d446a0b4bb90bf05d6f92eedeaabc97">osMessageQ</a>(MsgBox), NULL); <span class="comment">// create msg queue</span></div> <div class="line"> </div> <div class="line"> tid_thread1 = <a class="code" href="group__CMSIS__RTOS__ThreadMgmt.html#gac59b5713cb083702dce759c73fd90dff">osThreadCreate</a>(<a class="code" href="group__CMSIS__RTOS__ThreadMgmt.html#gaf0c7c6b5e09f8be198312144b5c9e453">osThread</a>(send_thread), NULL);</div> <div class="line"> tid_thread2 = <a class="code" href="group__CMSIS__RTOS__ThreadMgmt.html#gac59b5713cb083702dce759c73fd90dff">osThreadCreate</a>(<a class="code" href="group__CMSIS__RTOS__ThreadMgmt.html#gaf0c7c6b5e09f8be198312144b5c9e453">osThread</a>(recv_thread), NULL);</div> <div class="line"> :</div> <div class="line">}</div> </div><!-- fragment --> </div> </div> <a class="anchor" id="ga6c6892b8f2296cca6becd57ca2d7e1ae"></a> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#structosEvent">osEvent</a> osMessageGet </td> <td>(</td> <td class="paramtype"><a class="el" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> </td> <td class="paramname"><em>queue_id</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">uint32_t </td> <td class="paramname"><em>millisec</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramdir">[in]</td><td class="paramname">queue_id</td><td>message queue ID obtained with <a class="el" href="group__CMSIS__RTOS__Message.html#gaf3b9345cf426304d46565152bc26fb78">osMessageCreate</a>. </td></tr> <tr><td class="paramdir">[in]</td><td class="paramname">millisec</td><td><a class="el" href="functionOverview.html#CMSIS_RTOS_TimeOutValue">Timout Value</a> or 0 in case of no time-out. </td></tr> </table> </dd> </dl> <dl class="section return"><dt>Returns</dt><dd>event information that includes status code. </dd></dl> <dl class="section note"><dt>Note</dt><dd>MUST REMAIN UNCHANGED: <b>osMessageGet</b> shall be consistent in every CMSIS-RTOS.</dd></dl> <p>Suspend the execution of the current <b>RUNNING</b> thread until a message arrives. When a message is already in the queue, the function returns instantly with the message information.</p> <p>The argument <em>millisec</em> specifies how long the system waits for a message to become available. While the system waits the thread that is calling this function is put into the state <b>WAITING</b>. The <em>millisec</em> timeout value can have the following values:</p> <ul> <li>when <em>millisec</em> is 0, the function returns instantly.</li> <li>when <em>millisec</em> is set to <b>osWaitForever</b> the function will wait for an infinite time until a message arrives.</li> <li>all other values specify a time in millisecond for a timeout.</li> </ul> <dl class="section note"><dt>Note</dt><dd>The parameter <em>millisec</em> must be 0 for using this function in an ISR. </dd> <dd> <a class="el" href="functionOverview.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a> can call this function.</dd></dl> <p><b><a class="el" href="group__CMSIS__RTOS__Status.html">Status and Error Codes</a></b><br/> </p> <ul> <li><em>osOK:</em> no message is available in the queue and no timeout was specified.</li> <li><em>osEventTimeout:</em> no message has arrived during the given timeout period.</li> <li><em>osEventMessage:</em> message received, <em>value.p</em> contains the pointer to message.</li> <li><em>osErrorParameter:</em> a parameter is invalid or outside of a permitted range. </li> </ul> </div> </div> <a class="anchor" id="gac0dcf462fc92de8ffaba6cc004514a6d"></a> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname"><a class="el" href="group__CMSIS__RTOS__Status.html#gae2e091fefc4c767117727bd5aba4d99e">osStatus</a> osMessagePut </td> <td>(</td> <td class="paramtype"><a class="el" href="cmsis__os_8h.html#ad9ec70c32c6c521970636b521e12d17f">osMessageQId</a> </td> <td class="paramname"><em>queue_id</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">uint32_t </td> <td class="paramname"><em>info</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">uint32_t </td> <td class="paramname"><em>millisec</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramdir">[in]</td><td class="paramname">queue_id</td><td>message queue ID obtained with <a class="el" href="group__CMSIS__RTOS__Message.html#gaf3b9345cf426304d46565152bc26fb78">osMessageCreate</a>. </td></tr> <tr><td class="paramdir">[in]</td><td class="paramname">info</td><td>message information. </td></tr> <tr><td class="paramdir">[in]</td><td class="paramname">millisec</td><td><a class="el" href="functionOverview.html#CMSIS_RTOS_TimeOutValue">Timout Value</a> or 0 in case of no time-out. </td></tr> </table> </dd> </dl> <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function. </dd></dl> <dl class="section note"><dt>Note</dt><dd>MUST REMAIN UNCHANGED: <b>osMessagePut</b> shall be consistent in every CMSIS-RTOS.</dd></dl> <p>Put the message <em>info</em> in a message queue specified by <em>queue_id</em>.</p> <p>When the message queue is full, the system retries for a specified time with <em>millisec</em>. While the system retries the thread that is calling this function is put into the state <b>WAITING</b>. The <em>millisec</em> timeout can have the following values:</p> <ul> <li>when <em>millisec</em> is 0, the function returns instantly.</li> <li>when <em>millisec</em> is set to <b>osWaitForever</b> the function will wait for an infinite time until a message queue slot becomes available.</li> <li>all other values specify a time in millisecond for a timeout.</li> </ul> <dl class="section note"><dt>Note</dt><dd>The parameter <em>millisec</em> must be 0 for using this function in an ISR. </dd> <dd> <a class="el" href="functionOverview.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a> can call this function.</dd></dl> <p><b><a class="el" href="group__CMSIS__RTOS__Status.html">Status and Error Codes</a></b><br/> </p> <ul> <li><em>osOK:</em> the message is put into the queue.</li> <li><em>osErrorResource:</em> no memory in the queue was available.</li> <li><em>osErrorTimeoutResource:</em> no memory in the queue was available during the given time limit.</li> <li><em>osErrorParameter:</em> a parameter is invalid or outside of a permitted range. </li> </ul> </div> </div> </div><!-- contents --> </div><!-- doc-content --> <!-- start footer part --> <div id="nav-path" class="navpath"><!-- id is needed for treeview function! --> <ul> <li class="footer">Generated on Wed Feb 8 2017 10:21:02 for CMSIS-RTOS by ARM Ltd. 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