begriffs open source - cmsis/blob - main/RTOS2/group__CMSIS__RTOS__Message.html

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 128 <a href="#nested-classes">Data Structures</a> &#124;
 129 <a href="#func-members">Functions</a>  </div>
 130   <div class="headertitle"><div class="title">Message Queue<div class="ingroups"><a class="el" href="group__CMSIS__RTOS.html">CMSIS-RTOS2 API</a></div></div></div>
 131 </div><!--header-->
 132 <div class="contents">
 133
 134 <p>Exchange messages between threads in a FIFO-like operation.
 135 <a href="#details">More...</a></p>
 136 <table class="memberdecls">
 137 <tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="nested-classes" name="nested-classes"></a>
 138 Data Structures</h2></td></tr>
 139 <tr class="memitem:structosMessageQueueAttr__t"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#structosMessageQueueAttr__t">osMessageQueueAttr_t</a></td></tr>
 140 <tr class="memdesc:structosMessageQueueAttr__t"><td class="mdescLeft">&#160;</td><td class="mdescRight">Attributes structure for message queue.  <a href="group__CMSIS__RTOS__Message.html#structosMessageQueueAttr__t">More...</a><br /></td></tr>
 141 <tr class="separator:structosMessageQueueAttr__t"><td class="memSeparator" colspan="2">&#160;</td></tr>
 142 </table><table class="memberdecls">
 143 <tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="func-members" name="func-members"></a>
 144 Functions</h2></td></tr>
 145 <tr class="memitem:ga24e895a00f9d484db33aaf784c57bfed"><td class="memItemLeft" align="right" valign="top">osMessageQueueId_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a> (uint32_t msg_count, uint32_t msg_size, const <a class="el" href="group__CMSIS__RTOS__Message.html#structosMessageQueueAttr__t">osMessageQueueAttr_t</a> *attr)</td></tr>
 146 <tr class="memdesc:ga24e895a00f9d484db33aaf784c57bfed"><td class="mdescLeft">&#160;</td><td class="mdescRight">Create and Initialize a Message Queue object.  <br /></td></tr>
 147 <tr class="separator:ga24e895a00f9d484db33aaf784c57bfed"><td class="memSeparator" colspan="2">&#160;</td></tr>
 148 <tr class="memitem:gae7cf7bf2b97a5ae481fb60fcce99247a"><td class="memItemLeft" align="right" valign="top">const char *&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gae7cf7bf2b97a5ae481fb60fcce99247a">osMessageQueueGetName</a> (osMessageQueueId_t mq_id)</td></tr>
 149 <tr class="memdesc:gae7cf7bf2b97a5ae481fb60fcce99247a"><td class="mdescLeft">&#160;</td><td class="mdescRight">Get name of a Message Queue object.  <br /></td></tr>
 150 <tr class="separator:gae7cf7bf2b97a5ae481fb60fcce99247a"><td class="memSeparator" colspan="2">&#160;</td></tr>
 151 <tr class="memitem:gaa515fc8b956f721a8f72b2c505813bfc"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a> (osMessageQueueId_t mq_id, const void *msg_ptr, uint8_t msg_prio, uint32_t timeout)</td></tr>
 152 <tr class="memdesc:gaa515fc8b956f721a8f72b2c505813bfc"><td class="mdescLeft">&#160;</td><td class="mdescRight">Put a Message into a Queue or timeout if Queue is full.  <br /></td></tr>
 153 <tr class="separator:gaa515fc8b956f721a8f72b2c505813bfc"><td class="memSeparator" colspan="2">&#160;</td></tr>
 154 <tr class="memitem:gad90d4959466a7a65105061da8256ab9e"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gad90d4959466a7a65105061da8256ab9e">osMessageQueueGet</a> (osMessageQueueId_t mq_id, void *msg_ptr, uint8_t *msg_prio, uint32_t timeout)</td></tr>
 155 <tr class="memdesc:gad90d4959466a7a65105061da8256ab9e"><td class="mdescLeft">&#160;</td><td class="mdescRight">Get a Message from a Queue or timeout if Queue is empty.  <br /></td></tr>
 156 <tr class="separator:gad90d4959466a7a65105061da8256ab9e"><td class="memSeparator" colspan="2">&#160;</td></tr>
 157 <tr class="memitem:gac24f87d4f395e9e9c900c320e45ade8a"><td class="memItemLeft" align="right" valign="top">uint32_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gac24f87d4f395e9e9c900c320e45ade8a">osMessageQueueGetCapacity</a> (osMessageQueueId_t mq_id)</td></tr>
 158 <tr class="memdesc:gac24f87d4f395e9e9c900c320e45ade8a"><td class="mdescLeft">&#160;</td><td class="mdescRight">Get maximum number of messages in a Message Queue.  <br /></td></tr>
 159 <tr class="separator:gac24f87d4f395e9e9c900c320e45ade8a"><td class="memSeparator" colspan="2">&#160;</td></tr>
 160 <tr class="memitem:ga96d3d84069b20359de48109e28a1a89e"><td class="memItemLeft" align="right" valign="top">uint32_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#ga96d3d84069b20359de48109e28a1a89e">osMessageQueueGetMsgSize</a> (osMessageQueueId_t mq_id)</td></tr>
 161 <tr class="memdesc:ga96d3d84069b20359de48109e28a1a89e"><td class="mdescLeft">&#160;</td><td class="mdescRight">Get maximum message size in a Message Queue.  <br /></td></tr>
 162 <tr class="separator:ga96d3d84069b20359de48109e28a1a89e"><td class="memSeparator" colspan="2">&#160;</td></tr>
 163 <tr class="memitem:ga6a32ac394fcff568b251c160cc3014b2"><td class="memItemLeft" align="right" valign="top">uint32_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#ga6a32ac394fcff568b251c160cc3014b2">osMessageQueueGetCount</a> (osMessageQueueId_t mq_id)</td></tr>
 164 <tr class="memdesc:ga6a32ac394fcff568b251c160cc3014b2"><td class="mdescLeft">&#160;</td><td class="mdescRight">Get number of queued messages in a Message Queue.  <br /></td></tr>
 165 <tr class="separator:ga6a32ac394fcff568b251c160cc3014b2"><td class="memSeparator" colspan="2">&#160;</td></tr>
 166 <tr class="memitem:gaddf0904427436dd3880d46263c2dc9fa"><td class="memItemLeft" align="right" valign="top">uint32_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gaddf0904427436dd3880d46263c2dc9fa">osMessageQueueGetSpace</a> (osMessageQueueId_t mq_id)</td></tr>
 167 <tr class="memdesc:gaddf0904427436dd3880d46263c2dc9fa"><td class="mdescLeft">&#160;</td><td class="mdescRight">Get number of available slots for messages in a Message Queue.  <br /></td></tr>
 168 <tr class="separator:gaddf0904427436dd3880d46263c2dc9fa"><td class="memSeparator" colspan="2">&#160;</td></tr>
 169 <tr class="memitem:gac6dce7f9ad132d266292c2e979d861b4"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gac6dce7f9ad132d266292c2e979d861b4">osMessageQueueReset</a> (osMessageQueueId_t mq_id)</td></tr>
 170 <tr class="memdesc:gac6dce7f9ad132d266292c2e979d861b4"><td class="mdescLeft">&#160;</td><td class="mdescRight">Reset a Message Queue to initial empty state.  <br /></td></tr>
 171 <tr class="separator:gac6dce7f9ad132d266292c2e979d861b4"><td class="memSeparator" colspan="2">&#160;</td></tr>
 172 <tr class="memitem:gaba987f665444e0d83fa6a3a68bc72abe"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__CMSIS__RTOS__Message.html#gaba987f665444e0d83fa6a3a68bc72abe">osMessageQueueDelete</a> (osMessageQueueId_t mq_id)</td></tr>
 173 <tr class="memdesc:gaba987f665444e0d83fa6a3a68bc72abe"><td class="mdescLeft">&#160;</td><td class="mdescRight">Delete a Message Queue object.  <br /></td></tr>
 174 <tr class="separator:gaba987f665444e0d83fa6a3a68bc72abe"><td class="memSeparator" colspan="2">&#160;</td></tr>
 175 </table>
 176 <a name="details" id="details"></a><h2 class="groupheader">Description</h2>
 177 <p>Exchange messages between threads in a FIFO-like operation. </p>
 178 <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>
 179 <div class="image">
 180 <img src="MessageQueue.png" alt=""/>
 181 <div class="caption">
 182 CMSIS-RTOS Message Queue</div></div>
 183 <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>
 184 <dl class="section note"><dt>Note</dt><dd>The functions <a class="el" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a>, <a class="el" href="group__CMSIS__RTOS__Message.html#gad90d4959466a7a65105061da8256ab9e">osMessageQueueGet</a>, <a class="el" href="group__CMSIS__RTOS__Message.html#gac24f87d4f395e9e9c900c320e45ade8a">osMessageQueueGetCapacity</a>, <a class="el" href="group__CMSIS__RTOS__Message.html#ga96d3d84069b20359de48109e28a1a89e">osMessageQueueGetMsgSize</a>, <a class="el" href="group__CMSIS__RTOS__Message.html#ga6a32ac394fcff568b251c160cc3014b2">osMessageQueueGetCount</a>, <a class="el" href="group__CMSIS__RTOS__Message.html#gaddf0904427436dd3880d46263c2dc9fa">osMessageQueueGetSpace</a> can be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 185 <hr/><h2 class="groupheader">Data Structure Documentation</h2>
 186 <a name="structosMessageQueueAttr__t" id="structosMessageQueueAttr__t"></a>
 187 <h2 class="memtitle"><span class="permalink"><a href="#structosMessageQueueAttr__t">&#9670;&#160;</a></span>osMessageQueueAttr_t</h2>
 188
 189 <div class="memitem">
 190 <div class="memproto">
 191       <table class="memname">
 192         <tr>
 193           <td class="memname">struct osMessageQueueAttr_t</td>
 194         </tr>
 195       </table>
 196 </div><div class="memdoc">
 197 <div class="textblock"><p>Attributes structure for message queue. </p>
 198 <p>Specifies the following attributes for the <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a> function. </p>
 199 </div><table class="fieldtable">
 200 <tr><th colspan="3">Data Fields</th></tr>
 201 <tr><td class="fieldtype">
 202 <a id="ab74e6bf80237ddc4109968cedc58c151" name="ab74e6bf80237ddc4109968cedc58c151"></a>const char *</td>
 203 <td class="fieldname">
 204 name</td>
 205 <td class="fielddoc">
 206 name of the message queue <p>Pointer to a constant string with a human readable name (displayed during debugging) of the message queue object.</p>
 207 <p>Default: <span class="XML-Token">NULL</span> no name specified. </p>
 208 </td></tr>
 209 <tr><td class="fieldtype">
 210 <a id="a6e93b49cb79c12f768d72580c7731f30" name="a6e93b49cb79c12f768d72580c7731f30"></a>uint32_t</td>
 211 <td class="fieldname">
 212 attr_bits</td>
 213 <td class="fielddoc">
 214 attribute bits <p>Reserved for future use (must be set to '0' for future compatibility). </p>
 215 </td></tr>
 216 <tr><td class="fieldtype">
 217 <a id="a1e100dc33d403841ed3c344e3397868e" name="a1e100dc33d403841ed3c344e3397868e"></a>void *</td>
 218 <td class="fieldname">
 219 cb_mem</td>
 220 <td class="fielddoc">
 221 memory for control block <p>Pointer to a memory for the message queue control block object. Refer to <a class="el" href="usingOS2.html#CMSIS_RTOS_MemoryMgmt_Manual">Manual User-defined Allocation</a> for more information.</p>
 222 <p>Default: <span class="XML-Token">NULL</span> to use <a class="el" href="usingOS2.html#CMSIS_RTOS_MemoryMgmt_Automatic">Automatic Dynamic Allocation</a> for the message queue control block. </p>
 223 </td></tr>
 224 <tr><td class="fieldtype">
 225 <a id="aa55a4335d12dc2785dc00fdc292d1159" name="aa55a4335d12dc2785dc00fdc292d1159"></a>uint32_t</td>
 226 <td class="fieldname">
 227 cb_size</td>
 228 <td class="fielddoc">
 229 size of provided memory for control block <p>The size (in bytes) of memory block passed with <a class="el" href="group__CMSIS__RTOS__Message.html#a1e100dc33d403841ed3c344e3397868e">cb_mem</a>. Required value depends on the underlying kernel implementation.</p>
 230 <p>Default: <span class="XML-Token">0</span> as the default is no memory provided with <a class="el" href="group__CMSIS__RTOS__Message.html#a1e100dc33d403841ed3c344e3397868e">cb_mem</a>. </p>
 231 </td></tr>
 232 <tr><td class="fieldtype">
 233 <a id="a4e208dc0fb049b42c4b90cbd2791c5ad" name="a4e208dc0fb049b42c4b90cbd2791c5ad"></a>void *</td>
 234 <td class="fieldname">
 235 mq_mem</td>
 236 <td class="fielddoc">
 237 memory for data storage <p>Pointer to a memory for the message queue data. Refer to <a class="el" href="usingOS2.html#CMSIS_RTOS_MemoryMgmt_Manual">Manual User-defined Allocation</a> for more information.</p>
 238 <p>Default: <span class="XML-Token">NULL</span> to use <a class="el" href="usingOS2.html#CMSIS_RTOS_MemoryMgmt_Automatic">Automatic Dynamic Allocation</a> for the memory pool data. </p>
 239 </td></tr>
 240 <tr><td class="fieldtype">
 241 <a id="ac1cc09f875e20c926920b57bb83c70ee" name="ac1cc09f875e20c926920b57bb83c70ee"></a>uint32_t</td>
 242 <td class="fieldname">
 243 mq_size</td>
 244 <td class="fielddoc">
 245 size of provided memory for data storage <p>The size (in bytes) of memory block passed with <a class="el" href="group__CMSIS__RTOS__Message.html#a4e208dc0fb049b42c4b90cbd2791c5ad">mq_mem</a>. The minimum memory block size is <code>msg_count * msg_size</code> (parameters of the <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a> function). The <em>msg_size</em> is rounded up to a double even number to ensure 32-bit alignment of the memory blocks.</p>
 246 <p>Default: 0 as the default is no memory provided with <a class="el" href="group__CMSIS__RTOS__Message.html#a4e208dc0fb049b42c4b90cbd2791c5ad">mq_mem</a>. </p>
 247 </td></tr>
 248 </table>
 249
 250 </div>
 251 </div>
 252 <h2 class="groupheader">Function Documentation</h2>
 253 <a id="ga24e895a00f9d484db33aaf784c57bfed" name="ga24e895a00f9d484db33aaf784c57bfed"></a>
 254 <h2 class="memtitle"><span class="permalink"><a href="#ga24e895a00f9d484db33aaf784c57bfed">&#9670;&#160;</a></span>osMessageQueueNew()</h2>
 255
 256 <div class="memitem">
 257 <div class="memproto">
 258       <table class="memname">
 259         <tr>
 260           <td class="memname">osMessageQueueId_t osMessageQueueNew </td>
 261           <td>(</td>
 262           <td class="paramtype">uint32_t&#160;</td>
 263           <td class="paramname"><em>msg_count</em>, </td>
 264         </tr>
 265         <tr>
 266           <td class="paramkey"></td>
 267           <td></td>
 268           <td class="paramtype">uint32_t&#160;</td>
 269           <td class="paramname"><em>msg_size</em>, </td>
 270         </tr>
 271         <tr>
 272           <td class="paramkey"></td>
 273           <td></td>
 274           <td class="paramtype">const <a class="el" href="group__CMSIS__RTOS__Message.html#structosMessageQueueAttr__t">osMessageQueueAttr_t</a> *&#160;</td>
 275           <td class="paramname"><em>attr</em>&#160;</td>
 276         </tr>
 277         <tr>
 278           <td></td>
 279           <td>)</td>
 280           <td></td><td></td>
 281         </tr>
 282       </table>
 283 </div><div class="memdoc">
 284
 285 <p>Create and Initialize a Message Queue object. </p>
 286 <dl class="params"><dt>Parameters</dt><dd>
 287   <table class="params">
 288     <tr><td class="paramdir">[in]</td><td class="paramname">msg_count</td><td>maximum number of messages in queue. </td></tr>
 289     <tr><td class="paramdir">[in]</td><td class="paramname">msg_size</td><td>maximum message size in bytes. </td></tr>
 290     <tr><td class="paramdir">[in]</td><td class="paramname">attr</td><td>message queue attributes; NULL: default values. </td></tr>
 291   </table>
 292   </dd>
 293 </dl>
 294 <dl class="section return"><dt>Returns</dt><dd>message queue ID for reference by other functions or NULL in case of error.</dd></dl>
 295 <p>The function <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a> creates and initializes a message queue object. The function returns a message queue object identifier or <span class="XML-Token">NULL</span> in case of an error.</p>
 296 <p>The function can be called after kernel initialization with <a class="el" href="group__CMSIS__RTOS__KernelCtrl.html#gae818f6611d25ba3140bede410a52d659">osKernelInitialize</a>. It is possible to create message queue objects before the RTOS kernel is started with <a class="el" href="group__CMSIS__RTOS__KernelCtrl.html#ga9ae2cc00f0d89d7b6a307bba942b5221">osKernelStart</a>.</p>
 297 <p>The total amount of memory required for the message queue data is at least <code>msg_count * msg_size</code>. The <em>msg_size</em> is rounded up to a double even number to ensure 32-bit alignment of the memory blocks.</p>
 298 <p>The memory blocks allocated from the message queue have a fixed size defined with the parameter <code>msg_size</code>.</p>
 299 <dl class="section note"><dt>Note</dt><dd>This function <b>cannot</b> be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>.</dd></dl>
 300 <p><b>Code Example</b></p>
 301 <p>Refer to <a class="el" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a> </p>
 302
 303 </div>
 304 </div>
 305 <a id="gae7cf7bf2b97a5ae481fb60fcce99247a" name="gae7cf7bf2b97a5ae481fb60fcce99247a"></a>
 306 <h2 class="memtitle"><span class="permalink"><a href="#gae7cf7bf2b97a5ae481fb60fcce99247a">&#9670;&#160;</a></span>osMessageQueueGetName()</h2>
 307
 308 <div class="memitem">
 309 <div class="memproto">
 310       <table class="memname">
 311         <tr>
 312           <td class="memname">const char * osMessageQueueGetName </td>
 313           <td>(</td>
 314           <td class="paramtype">osMessageQueueId_t&#160;</td>
 315           <td class="paramname"><em>mq_id</em></td><td>)</td>
 316           <td></td>
 317         </tr>
 318       </table>
 319 </div><div class="memdoc">
 320
 321 <p>Get name of a Message Queue object. </p>
 322 <dl class="params"><dt>Parameters</dt><dd>
 323   <table class="params">
 324     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 325   </table>
 326   </dd>
 327 </dl>
 328 <dl class="section return"><dt>Returns</dt><dd>name as null-terminated string.</dd></dl>
 329 <p>The function <b>osMessageQueueGetName</b> returns the pointer to the name string of the message queue identified by parameter <em>mq_id</em> or <span class="XML-Token">NULL</span> in case of an error.</p>
 330 <dl class="section note"><dt>Note</dt><dd>This function may be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 331
 332 </div>
 333 </div>
 334 <a id="gaa515fc8b956f721a8f72b2c505813bfc" name="gaa515fc8b956f721a8f72b2c505813bfc"></a>
 335 <h2 class="memtitle"><span class="permalink"><a href="#gaa515fc8b956f721a8f72b2c505813bfc">&#9670;&#160;</a></span>osMessageQueuePut()</h2>
 336
 337 <div class="memitem">
 338 <div class="memproto">
 339       <table class="memname">
 340         <tr>
 341           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueuePut </td>
 342           <td>(</td>
 343           <td class="paramtype">osMessageQueueId_t&#160;</td>
 344           <td class="paramname"><em>mq_id</em>, </td>
 345         </tr>
 346         <tr>
 347           <td class="paramkey"></td>
 348           <td></td>
 349           <td class="paramtype">const void *&#160;</td>
 350           <td class="paramname"><em>msg_ptr</em>, </td>
 351         </tr>
 352         <tr>
 353           <td class="paramkey"></td>
 354           <td></td>
 355           <td class="paramtype">uint8_t&#160;</td>
 356           <td class="paramname"><em>msg_prio</em>, </td>
 357         </tr>
 358         <tr>
 359           <td class="paramkey"></td>
 360           <td></td>
 361           <td class="paramtype">uint32_t&#160;</td>
 362           <td class="paramname"><em>timeout</em>&#160;</td>
 363         </tr>
 364         <tr>
 365           <td></td>
 366           <td>)</td>
 367           <td></td><td></td>
 368         </tr>
 369       </table>
 370 </div><div class="memdoc">
 371
 372 <p>Put a Message into a Queue or timeout if Queue is full. </p>
 373 <dl class="params"><dt>Parameters</dt><dd>
 374   <table class="params">
 375     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 376     <tr><td class="paramdir">[in]</td><td class="paramname">msg_ptr</td><td>pointer to buffer with message to put into a queue. </td></tr>
 377     <tr><td class="paramdir">[in]</td><td class="paramname">msg_prio</td><td>message priority. </td></tr>
 378     <tr><td class="paramdir">[in]</td><td class="paramname">timeout</td><td><a class="el" href="usingOS2.html#CMSIS_RTOS_TimeOutValue">Timeout Values</a> or 0 in case of no time-out. </td></tr>
 379   </table>
 380   </dd>
 381 </dl>
 382 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 383 <p>The blocking function <b>osMessageQueuePut</b> puts the message pointed to by <em>msg_ptr</em> into the the message queue specified by parameter <em>mq_id</em>. The parameter <em>msg_prio</em> is used to sort message according their priority (higher numbers indicate a higher priority) on insertion.</p>
 384 <p>The parameter <em>timeout</em> specifies how long the system waits to put the message into the queue. While the system waits, the thread that is calling this function is put into the <a class="el" href="group__CMSIS__RTOS__ThreadMgmt.html#ThreadStates">BLOCKED</a> state. The parameter <a class="el" href="usingOS2.html#CMSIS_RTOS_TimeOutValue">timeout</a> can have the following values:</p><ul>
 385 <li>when <em>timeout</em> is <span class="XML-Token">0</span>, the function returns instantly (i.e. try semantics).</li>
 386 <li>when <em>timeout</em> is set to <b>osWaitForever</b> the function will wait for an infinite time until the message is delivered (i.e. wait semantics).</li>
 387 <li>all other values specify a time in kernel ticks for a timeout (i.e. timed-wait semantics).</li>
 388 </ul>
 389 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 390 <li><em>osOK:</em> the message has been put into the queue.</li>
 391 <li><em>osErrorTimeout:</em> the message could not be put into the queue in the given time (wait-timed semantics).</li>
 392 <li><em>osErrorResource:</em> not enough space in the queue (try semantics).</li>
 393 <li><em>osErrorParameter:</em> parameter <em>mq_id</em> is <span class="XML-Token">NULL</span> or invalid, non-zero timeout specified in an ISR.</li>
 394 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 395 </ul>
 396 <dl class="section note"><dt>Note</dt><dd>May be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a> if the parameter <em>timeout</em> is set to <span class="XML-Token">0</span>.</dd></dl>
 397 <p><b>Code Example:</b> </p><div class="fragment"><div class="line"><span class="preprocessor">#include &quot;cmsis_os2.h&quot;</span>                          <span class="comment">// CMSIS RTOS header file</span></div>
 398 <div class="line"> </div>
 399 <div class="line"><span class="comment">/*----------------------------------------------------------------------------</span></div>
 400 <div class="line"><span class="comment"> *      Message Queue creation &amp; usage</span></div>
 401 <div class="line"><span class="comment"> *---------------------------------------------------------------------------*/</span></div>
 402 <div class="line"> </div>
 403 <div class="line"><span class="preprocessor">#define MSGQUEUE_OBJECTS 16                     </span><span class="comment">// number of Message Queue Objects</span></div>
 404 <div class="line"> </div>
 405 <div class="line"><span class="keyword">typedef</span> <span class="keyword">struct </span>{                                <span class="comment">// object data type</span></div>
 406 <div class="line">  uint8_t Buf[32];</div>
 407 <div class="line">  uint8_t Idx;</div>
 408 <div class="line">} MSGQUEUE_OBJ_t;</div>
 409 <div class="line"> </div>
 410 <div class="line">osMessageQueueId_t mid_MsgQueue;                <span class="comment">// message queue id</span></div>
 411 <div class="line"> </div>
 412 <div class="line"><a class="code hl_typedef" href="group__CMSIS__RTOS__ThreadMgmt.html#gaa6c32fe2a3e0a2e01f212d55b02e51c7">osThreadId_t</a> tid_Thread_MsgQueue1;              <span class="comment">// thread id 1</span></div>
 413 <div class="line"><a class="code hl_typedef" href="group__CMSIS__RTOS__ThreadMgmt.html#gaa6c32fe2a3e0a2e01f212d55b02e51c7">osThreadId_t</a> tid_Thread_MsgQueue2;              <span class="comment">// thread id 2</span></div>
 414 <div class="line"> </div>
 415 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue1 (<span class="keywordtype">void</span> *argument);         <span class="comment">// thread function 1</span></div>
 416 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue2 (<span class="keywordtype">void</span> *argument);         <span class="comment">// thread function 2</span></div>
 417 <div class="line"> </div>
 418 <div class="line"><span class="keywordtype">int</span> Init_MsgQueue (<span class="keywordtype">void</span>) {</div>
 419 <div class="line"> </div>
 420 <div class="line">  mid_MsgQueue = <a class="code hl_function" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed" title="Create and Initialize a Message Queue object.">osMessageQueueNew</a>(MSGQUEUE_OBJECTS, <span class="keyword">sizeof</span>(MSGQUEUE_OBJ_t), NULL);</div>
 421 <div class="line">  <span class="keywordflow">if</span> (mid_MsgQueue == NULL) {</div>
 422 <div class="line">    ; <span class="comment">// Message Queue object not created, handle failure</span></div>
 423 <div class="line">  }</div>
 424 <div class="line"> </div>
 425 <div class="line">  tid_Thread_MsgQueue1 = <a class="code hl_function" href="group__CMSIS__RTOS__ThreadMgmt.html#ga48d68b8666d99d28fa646ee1d2182b8f" title="Create a thread and add it to Active Threads.">osThreadNew</a>(Thread_MsgQueue1, NULL, NULL);</div>
 426 <div class="line">  <span class="keywordflow">if</span> (tid_Thread_MsgQueue1 == NULL) {</div>
 427 <div class="line">    <span class="keywordflow">return</span>(-1);</div>
 428 <div class="line">  }</div>
 429 <div class="line">  tid_Thread_MsgQueue2 = <a class="code hl_function" href="group__CMSIS__RTOS__ThreadMgmt.html#ga48d68b8666d99d28fa646ee1d2182b8f" title="Create a thread and add it to Active Threads.">osThreadNew</a>(Thread_MsgQueue2, NULL, NULL);</div>
 430 <div class="line">  <span class="keywordflow">if</span> (tid_Thread_MsgQueue2 == NULL) {</div>
 431 <div class="line">    <span class="keywordflow">return</span>(-1);</div>
 432 <div class="line">  }</div>
 433 <div class="line"> </div>
 434 <div class="line">  <span class="keywordflow">return</span>(0);</div>
 435 <div class="line">}</div>
 436 <div class="line"> </div>
 437 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue1 (<span class="keywordtype">void</span> *argument) {</div>
 438 <div class="line">  MSGQUEUE_OBJ_t msg;</div>
 439 <div class="line"> </div>
 440 <div class="line">  <span class="keywordflow">while</span> (1) {</div>
 441 <div class="line">    ; <span class="comment">// Insert thread code here...</span></div>
 442 <div class="line">    msg.Buf[0] = 0x55U;                                         <span class="comment">// do some work...</span></div>
 443 <div class="line">    msg.Idx    = 0U;</div>
 444 <div class="line">    <a class="code hl_function" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc" title="Put a Message into a Queue or timeout if Queue is full.">osMessageQueuePut</a>(mid_MsgQueue, &amp;msg, 0U, 0U);</div>
 445 <div class="line">    <a class="code hl_function" href="group__CMSIS__RTOS__ThreadMgmt.html#gad01c7ec26535b1de6b018bb9466720e2" title="Pass control to next thread that is in state READY.">osThreadYield</a>();                                            <span class="comment">// suspend thread</span></div>
 446 <div class="line">  }</div>
 447 <div class="line">}</div>
 448 <div class="line"> </div>
 449 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue2 (<span class="keywordtype">void</span> *argument) {</div>
 450 <div class="line">  MSGQUEUE_OBJ_t msg;</div>
 451 <div class="line">  <a class="code hl_enumeration" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e" title="Status code values returned by CMSIS-RTOS functions.">osStatus_t</a> status;</div>
 452 <div class="line"> </div>
 453 <div class="line">  <span class="keywordflow">while</span> (1) {</div>
 454 <div class="line">    ; <span class="comment">// Insert thread code here...</span></div>
 455 <div class="line">    status = <a class="code hl_function" href="group__CMSIS__RTOS__Message.html#gad90d4959466a7a65105061da8256ab9e" title="Get a Message from a Queue or timeout if Queue is empty.">osMessageQueueGet</a>(mid_MsgQueue, &amp;msg, NULL, 0U);   <span class="comment">// wait for message</span></div>
 456 <div class="line">    <span class="keywordflow">if</span> (status == <a class="code hl_enumvalue" href="group__CMSIS__RTOS__Definitions.html#gga6c0dbe6069e4e7f47bb4cd32ae2b813eab17c65ad8b5bae759882b41c5bf35cda" title="Operation completed successfully.">osOK</a>) {</div>
 457 <div class="line">      ; <span class="comment">// process data</span></div>
 458 <div class="line">    }</div>
 459 <div class="line">  }</div>
 460 <div class="line">}</div>
 461 </div><!-- fragment -->
 462 </div>
 463 </div>
 464 <a id="gad90d4959466a7a65105061da8256ab9e" name="gad90d4959466a7a65105061da8256ab9e"></a>
 465 <h2 class="memtitle"><span class="permalink"><a href="#gad90d4959466a7a65105061da8256ab9e">&#9670;&#160;</a></span>osMessageQueueGet()</h2>
 466
 467 <div class="memitem">
 468 <div class="memproto">
 469       <table class="memname">
 470         <tr>
 471           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueueGet </td>
 472           <td>(</td>
 473           <td class="paramtype">osMessageQueueId_t&#160;</td>
 474           <td class="paramname"><em>mq_id</em>, </td>
 475         </tr>
 476         <tr>
 477           <td class="paramkey"></td>
 478           <td></td>
 479           <td class="paramtype">void *&#160;</td>
 480           <td class="paramname"><em>msg_ptr</em>, </td>
 481         </tr>
 482         <tr>
 483           <td class="paramkey"></td>
 484           <td></td>
 485           <td class="paramtype">uint8_t *&#160;</td>
 486           <td class="paramname"><em>msg_prio</em>, </td>
 487         </tr>
 488         <tr>
 489           <td class="paramkey"></td>
 490           <td></td>
 491           <td class="paramtype">uint32_t&#160;</td>
 492           <td class="paramname"><em>timeout</em>&#160;</td>
 493         </tr>
 494         <tr>
 495           <td></td>
 496           <td>)</td>
 497           <td></td><td></td>
 498         </tr>
 499       </table>
 500 </div><div class="memdoc">
 501
 502 <p>Get a Message from a Queue or timeout if Queue is empty. </p>
 503 <dl class="params"><dt>Parameters</dt><dd>
 504   <table class="params">
 505     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 506     <tr><td class="paramdir">[out]</td><td class="paramname">msg_ptr</td><td>pointer to buffer for message to get from a queue. </td></tr>
 507     <tr><td class="paramdir">[out]</td><td class="paramname">msg_prio</td><td>pointer to buffer for message priority or NULL. </td></tr>
 508     <tr><td class="paramdir">[in]</td><td class="paramname">timeout</td><td><a class="el" href="usingOS2.html#CMSIS_RTOS_TimeOutValue">Timeout Values</a> or 0 in case of no time-out. </td></tr>
 509   </table>
 510   </dd>
 511 </dl>
 512 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 513 <p>The function <b>osMessageQueueGet</b> retrieves a message from the message queue specified by the parameter <em>mq_id</em> and saves it to the buffer pointed to by the parameter <em>msg_ptr</em>. The message priority is stored to parameter <em>msg_prio</em> if not token{NULL}.</p>
 514 <p>The parameter <em>timeout</em> specifies how long the system waits to retrieve the message from the queue. While the system waits, the thread that is calling this function is put into the <a class="el" href="group__CMSIS__RTOS__ThreadMgmt.html#ThreadStates">BLOCKED</a> state. The parameter <a class="el" href="usingOS2.html#CMSIS_RTOS_TimeOutValue">timeout</a> can have the following values:</p><ul>
 515 <li>when <em>timeout</em> is <span class="XML-Token">0</span>, the function returns instantly (i.e. try semantics).</li>
 516 <li>when <em>timeout</em> is set to <b>osWaitForever</b> the function will wait for an infinite time until the message is retrieved (i.e. wait semantics).</li>
 517 <li>all other values specify a time in kernel ticks for a timeout (i.e. timed-wait semantics).</li>
 518 </ul>
 519 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 520 <li><em>osOK:</em> the message has been retrieved from the queue.</li>
 521 <li><em>osErrorTimeout:</em> the message could not be retrieved from the queue in the given time (timed-wait semantics).</li>
 522 <li><em>osErrorResource:</em> nothing to get from the queue (try semantics).</li>
 523 <li><em>osErrorParameter:</em> parameter <em>mq_id</em> is <span class="XML-Token">NULL</span> or invalid, non-zero timeout specified in an ISR.</li>
 524 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 525 </ul>
 526 <dl class="section note"><dt>Note</dt><dd>May be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a> if the parameter <em>timeout</em> is set to <span class="XML-Token">0</span>.</dd></dl>
 527 <p><b>Code Example</b></p>
 528 <p>Refer to <a class="el" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a> </p>
 529
 530 </div>
 531 </div>
 532 <a id="gac24f87d4f395e9e9c900c320e45ade8a" name="gac24f87d4f395e9e9c900c320e45ade8a"></a>
 533 <h2 class="memtitle"><span class="permalink"><a href="#gac24f87d4f395e9e9c900c320e45ade8a">&#9670;&#160;</a></span>osMessageQueueGetCapacity()</h2>
 534
 535 <div class="memitem">
 536 <div class="memproto">
 537       <table class="memname">
 538         <tr>
 539           <td class="memname">uint32_t osMessageQueueGetCapacity </td>
 540           <td>(</td>
 541           <td class="paramtype">osMessageQueueId_t&#160;</td>
 542           <td class="paramname"><em>mq_id</em></td><td>)</td>
 543           <td></td>
 544         </tr>
 545       </table>
 546 </div><div class="memdoc">
 547
 548 <p>Get maximum number of messages in a Message Queue. </p>
 549 <dl class="params"><dt>Parameters</dt><dd>
 550   <table class="params">
 551     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 552   </table>
 553   </dd>
 554 </dl>
 555 <dl class="section return"><dt>Returns</dt><dd>maximum number of messages.</dd></dl>
 556 <p>The function <b>osMessageQueueGetCapacity</b> returns the maximum number of messages in the message queue object specified by parameter <em>mq_id</em> or <span class="XML-Token">0</span> in case of an error.</p>
 557 <dl class="section note"><dt>Note</dt><dd>This function may be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 558
 559 </div>
 560 </div>
 561 <a id="ga96d3d84069b20359de48109e28a1a89e" name="ga96d3d84069b20359de48109e28a1a89e"></a>
 562 <h2 class="memtitle"><span class="permalink"><a href="#ga96d3d84069b20359de48109e28a1a89e">&#9670;&#160;</a></span>osMessageQueueGetMsgSize()</h2>
 563
 564 <div class="memitem">
 565 <div class="memproto">
 566       <table class="memname">
 567         <tr>
 568           <td class="memname">uint32_t osMessageQueueGetMsgSize </td>
 569           <td>(</td>
 570           <td class="paramtype">osMessageQueueId_t&#160;</td>
 571           <td class="paramname"><em>mq_id</em></td><td>)</td>
 572           <td></td>
 573         </tr>
 574       </table>
 575 </div><div class="memdoc">
 576
 577 <p>Get maximum message size in a Message Queue. </p>
 578 <dl class="params"><dt>Parameters</dt><dd>
 579   <table class="params">
 580     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 581   </table>
 582   </dd>
 583 </dl>
 584 <dl class="section return"><dt>Returns</dt><dd>maximum message size in bytes.</dd></dl>
 585 <p>The function <b>osMessageQueueGetMsgSize</b> returns the maximum message size in bytes for the message queue object specified by parameter <em>mq_id</em> or <span class="XML-Token">0</span> in case of an error.</p>
 586 <dl class="section note"><dt>Note</dt><dd>This function may be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 587
 588 </div>
 589 </div>
 590 <a id="ga6a32ac394fcff568b251c160cc3014b2" name="ga6a32ac394fcff568b251c160cc3014b2"></a>
 591 <h2 class="memtitle"><span class="permalink"><a href="#ga6a32ac394fcff568b251c160cc3014b2">&#9670;&#160;</a></span>osMessageQueueGetCount()</h2>
 592
 593 <div class="memitem">
 594 <div class="memproto">
 595       <table class="memname">
 596         <tr>
 597           <td class="memname">uint32_t osMessageQueueGetCount </td>
 598           <td>(</td>
 599           <td class="paramtype">osMessageQueueId_t&#160;</td>
 600           <td class="paramname"><em>mq_id</em></td><td>)</td>
 601           <td></td>
 602         </tr>
 603       </table>
 604 </div><div class="memdoc">
 605
 606 <p>Get number of queued messages in a Message Queue. </p>
 607 <dl class="params"><dt>Parameters</dt><dd>
 608   <table class="params">
 609     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 610   </table>
 611   </dd>
 612 </dl>
 613 <dl class="section return"><dt>Returns</dt><dd>number of queued messages.</dd></dl>
 614 <p>The function <b>osMessageQueueGetCount</b> returns the number of queued messages in the message queue object specified by parameter <em>mq_id</em> or <span class="XML-Token">0</span> in case of an error.</p>
 615 <dl class="section note"><dt>Note</dt><dd>This function may be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 616
 617 </div>
 618 </div>
 619 <a id="gaddf0904427436dd3880d46263c2dc9fa" name="gaddf0904427436dd3880d46263c2dc9fa"></a>
 620 <h2 class="memtitle"><span class="permalink"><a href="#gaddf0904427436dd3880d46263c2dc9fa">&#9670;&#160;</a></span>osMessageQueueGetSpace()</h2>
 621
 622 <div class="memitem">
 623 <div class="memproto">
 624       <table class="memname">
 625         <tr>
 626           <td class="memname">uint32_t osMessageQueueGetSpace </td>
 627           <td>(</td>
 628           <td class="paramtype">osMessageQueueId_t&#160;</td>
 629           <td class="paramname"><em>mq_id</em></td><td>)</td>
 630           <td></td>
 631         </tr>
 632       </table>
 633 </div><div class="memdoc">
 634
 635 <p>Get number of available slots for messages in a Message Queue. </p>
 636 <dl class="params"><dt>Parameters</dt><dd>
 637   <table class="params">
 638     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 639   </table>
 640   </dd>
 641 </dl>
 642 <dl class="section return"><dt>Returns</dt><dd>number of available slots for messages.</dd></dl>
 643 <p>The function <b>osMessageQueueGetSpace</b> returns the number available slots for messages in the message queue object specified by parameter <em>mq_id</em> or <span class="XML-Token">0</span> in case of an error.</p>
 644 <dl class="section note"><dt>Note</dt><dd>This function may be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 645
 646 </div>
 647 </div>
 648 <a id="gac6dce7f9ad132d266292c2e979d861b4" name="gac6dce7f9ad132d266292c2e979d861b4"></a>
 649 <h2 class="memtitle"><span class="permalink"><a href="#gac6dce7f9ad132d266292c2e979d861b4">&#9670;&#160;</a></span>osMessageQueueReset()</h2>
 650
 651 <div class="memitem">
 652 <div class="memproto">
 653       <table class="memname">
 654         <tr>
 655           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueueReset </td>
 656           <td>(</td>
 657           <td class="paramtype">osMessageQueueId_t&#160;</td>
 658           <td class="paramname"><em>mq_id</em></td><td>)</td>
 659           <td></td>
 660         </tr>
 661       </table>
 662 </div><div class="memdoc">
 663
 664 <p>Reset a Message Queue to initial empty state. </p>
 665 <dl class="params"><dt>Parameters</dt><dd>
 666   <table class="params">
 667     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 668   </table>
 669   </dd>
 670 </dl>
 671 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 672 <p>The function <b>osMessageQueueReset</b> resets the message queue specified by the parameter <em>mq_id</em>.</p>
 673 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 674 <li><em>osOK:</em> the message queue has been rest.</li>
 675 <li><em>osErrorParameter:</em> parameter <em>mq_id</em> is <span class="XML-Token">NULL</span> or invalid.</li>
 676 <li><em>osErrorResource:</em> the message queue is in an invalid state.</li>
 677 <li><em>osErrorISR:</em> <b>osMessageQueueReset</b> cannot be called from interrupt service routines.</li>
 678 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 679 </ul>
 680 <dl class="section note"><dt>Note</dt><dd>This function <b>cannot</b> be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 681
 682 </div>
 683 </div>
 684 <a id="gaba987f665444e0d83fa6a3a68bc72abe" name="gaba987f665444e0d83fa6a3a68bc72abe"></a>
 685 <h2 class="memtitle"><span class="permalink"><a href="#gaba987f665444e0d83fa6a3a68bc72abe">&#9670;&#160;</a></span>osMessageQueueDelete()</h2>
 686
 687 <div class="memitem">
 688 <div class="memproto">
 689       <table class="memname">
 690         <tr>
 691           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueueDelete </td>
 692           <td>(</td>
 693           <td class="paramtype">osMessageQueueId_t&#160;</td>
 694           <td class="paramname"><em>mq_id</em></td><td>)</td>
 695           <td></td>
 696         </tr>
 697       </table>
 698 </div><div class="memdoc">
 699
 700 <p>Delete a Message Queue object. </p>
 701 <dl class="params"><dt>Parameters</dt><dd>
 702   <table class="params">
 703     <tr><td class="paramdir">[in]</td><td class="paramname">mq_id</td><td>message queue ID obtained by <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>. </td></tr>
 704   </table>
 705   </dd>
 706 </dl>
 707 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 708 <p>The function <b>osMessageQueueDelete</b> deletes a message queue object specified by parameter <em>mq_id</em>. It releases internal memory obtained for message queue handling. After this call, the <em>mq_id</em> is no longer valid and cannot be used. The message queue may be created again using the function <a class="el" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>.</p>
 709 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 710 <li><em>osOK:</em> the message queue object has been deleted.</li>
 711 <li><em>osErrorParameter:</em> parameter <em>mq_id</em> is <span class="XML-Token">NULL</span> or invalid.</li>
 712 <li><em>osErrorResource:</em> the message queue is in an invalid state.</li>
 713 <li><em>osErrorISR:</em> <b>osMessageQueueDelete</b> cannot be called from interrupt service routines.</li>
 714 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 715 </ul>
 716 <dl class="section note"><dt>Note</dt><dd>This function <b>cannot</b> be called from <a class="el" href="usingOS2.html#CMSIS_RTOS_ISR_Calls">Interrupt Service Routines</a>. </dd></dl>
 717
 718 </div>
 719 </div>
 720 </div><!-- contents -->
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