begriffs open source - cmsis/blob - main/RTOS2/html/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-RTOS API v2</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"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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> (<a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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><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>
 178 <div class="image">
 179 <img src="MessageQueue.png" alt=""/>
 180 <div class="caption">
 181 CMSIS-RTOS Message Queue</div></div>
 182 <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>
 183 <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 Interrupt Service Routines. </dd>
 184 <dd>
 185 Refer to msgQueueConfig for RTX5 configuration options. </dd></dl>
 186 <hr/><h2 class="groupheader">Data Structure Documentation</h2>
 187 <a name="structosMessageQueueAttr__t" id="structosMessageQueueAttr__t"></a>
 188 <h2 class="memtitle"><span class="permalink"><a href="#structosMessageQueueAttr__t">&#9670;&#160;</a></span>osMessageQueueAttr_t</h2>
 189
 190 <div class="memitem">
 191 <div class="memproto">
 192       <table class="memname">
 193         <tr>
 194           <td class="memname">struct osMessageQueueAttr_t</td>
 195         </tr>
 196       </table>
 197 </div><div class="memdoc">
 198 <div class="textblock"><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 StaticObjectMemory for more information.</p>
 222 <p>Default: <span class="XML-Token">NULL</span> to use <a class="el" href="group__CMSIS__RTOS__MemoryMgmt.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>. For RTX, the minimum value is defined with osRtxMessageQueueCbSize (higher values are permitted).</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 StaticObjectMemory for more information.</p>
 238 <p>Default: <span class="XML-Token">NULL</span> to use <a class="el" href="group__CMSIS__RTOS__MemoryMgmt.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"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> 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 <dl class="params"><dt>Parameters</dt><dd>
 285   <table class="params">
 286     <tr><td class="paramdir">[in]</td><td class="paramname">msg_count</td><td>maximum number of messages in queue. </td></tr>
 287     <tr><td class="paramdir">[in]</td><td class="paramname">msg_size</td><td>maximum message size in bytes. </td></tr>
 288     <tr><td class="paramdir">[in]</td><td class="paramname">attr</td><td>message queue attributes; NULL: default values. </td></tr>
 289   </table>
 290   </dd>
 291 </dl>
 292 <dl class="section return"><dt>Returns</dt><dd>message queue ID for reference by other functions or NULL in case of error.</dd></dl>
 293 <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>
 294 <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>
 295 <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>
 296 <p>The memory blocks allocated from the message queue have a fixed size defined with the parameter <code>msg_size</code>.</p>
 297 <dl class="section note"><dt>Note</dt><dd>This function <b>cannot</b> be called from Interrupt Service Routines.</dd></dl>
 298 <p><b>Code Example</b></p>
 299 <p>Refer to <a class="el" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a> </p>
 300
 301 </div>
 302 </div>
 303 <a id="gae7cf7bf2b97a5ae481fb60fcce99247a" name="gae7cf7bf2b97a5ae481fb60fcce99247a"></a>
 304 <h2 class="memtitle"><span class="permalink"><a href="#gae7cf7bf2b97a5ae481fb60fcce99247a">&#9670;&#160;</a></span>osMessageQueueGetName()</h2>
 305
 306 <div class="memitem">
 307 <div class="memproto">
 308       <table class="memname">
 309         <tr>
 310           <td class="memname">const char * osMessageQueueGetName </td>
 311           <td>(</td>
 312           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 313           <td class="paramname"><em>mq_id</em></td><td>)</td>
 314           <td></td>
 315         </tr>
 316       </table>
 317 </div><div class="memdoc">
 318 <dl class="params"><dt>Parameters</dt><dd>
 319   <table class="params">
 320     <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>
 321   </table>
 322   </dd>
 323 </dl>
 324 <dl class="section return"><dt>Returns</dt><dd>name as null-terminated string.</dd></dl>
 325 <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>
 326 <dl class="section note"><dt>Note</dt><dd>This function may be called from Interrupt Service Routines. </dd></dl>
 327
 328 </div>
 329 </div>
 330 <a id="gaa515fc8b956f721a8f72b2c505813bfc" name="gaa515fc8b956f721a8f72b2c505813bfc"></a>
 331 <h2 class="memtitle"><span class="permalink"><a href="#gaa515fc8b956f721a8f72b2c505813bfc">&#9670;&#160;</a></span>osMessageQueuePut()</h2>
 332
 333 <div class="memitem">
 334 <div class="memproto">
 335       <table class="memname">
 336         <tr>
 337           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueuePut </td>
 338           <td>(</td>
 339           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 340           <td class="paramname"><em>mq_id</em>, </td>
 341         </tr>
 342         <tr>
 343           <td class="paramkey"></td>
 344           <td></td>
 345           <td class="paramtype">const void *&#160;</td>
 346           <td class="paramname"><em>msg_ptr</em>, </td>
 347         </tr>
 348         <tr>
 349           <td class="paramkey"></td>
 350           <td></td>
 351           <td class="paramtype">uint8_t&#160;</td>
 352           <td class="paramname"><em>msg_prio</em>, </td>
 353         </tr>
 354         <tr>
 355           <td class="paramkey"></td>
 356           <td></td>
 357           <td class="paramtype">uint32_t&#160;</td>
 358           <td class="paramname"><em>timeout</em>&#160;</td>
 359         </tr>
 360         <tr>
 361           <td></td>
 362           <td>)</td>
 363           <td></td><td></td>
 364         </tr>
 365       </table>
 366 </div><div class="memdoc">
 367 <dl class="params"><dt>Parameters</dt><dd>
 368   <table class="params">
 369     <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>
 370     <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>
 371     <tr><td class="paramdir">[in]</td><td class="paramname">msg_prio</td><td>message priority. </td></tr>
 372     <tr><td class="paramdir">[in]</td><td class="paramname">timeout</td><td>CMSIS_RTOS_TimeOutValue or 0 in case of no time-out. </td></tr>
 373   </table>
 374   </dd>
 375 </dl>
 376 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 377 <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>
 378 <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 timeout can have the following values:</p><ul>
 379 <li>when <em>timeout</em> is <span class="XML-Token">0</span>, the function returns instantly (i.e. try semantics).</li>
 380 <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>
 381 <li>all other values specify a time in kernel ticks for a timeout (i.e. timed-wait semantics).</li>
 382 </ul>
 383 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 384 <li><em>osOK:</em> the message has been put into the queue.</li>
 385 <li><em>osErrorTimeout:</em> the message could not be put into the queue in the given time (wait-timed semantics).</li>
 386 <li><em>osErrorResource:</em> not enough space in the queue (try semantics).</li>
 387 <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>
 388 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 389 </ul>
 390 <dl class="section note"><dt>Note</dt><dd>May be called from Interrupt Service Routines if the parameter <em>timeout</em> is set to <span class="XML-Token">0</span>.</dd></dl>
 391 <p><b>Code Example:</b> </p><div class="fragment"><div class="line"><span class="preprocessor">#include &quot;<a class="code" href="cmsis__os2_8h.html">cmsis_os2.h</a>&quot;</span>                          <span class="comment">// CMSIS RTOS header file</span></div>
 392 <div class="line"> </div>
 393 <div class="line"><span class="comment">/*----------------------------------------------------------------------------</span></div>
 394 <div class="line"><span class="comment"> *      Message Queue creation &amp; usage</span></div>
 395 <div class="line"><span class="comment"> *---------------------------------------------------------------------------*/</span></div>
 396 <div class="line"> </div>
 397 <div class="line"><span class="preprocessor">#define MSGQUEUE_OBJECTS 16                     </span><span class="comment">// number of Message Queue Objects</span></div>
 398 <div class="line"> </div>
 399 <div class="line"><span class="keyword">typedef</span> <span class="keyword">struct </span>{                                <span class="comment">// object data type</span></div>
 400 <div class="line">  uint8_t Buf[32];</div>
 401 <div class="line">  uint8_t Idx;</div>
 402 <div class="line">} MSGQUEUE_OBJ_t;</div>
 403 <div class="line"> </div>
 404 <div class="line"><a class="code hl_typedef" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a> mid_MsgQueue;                <span class="comment">// message queue id</span></div>
 405 <div class="line"> </div>
 406 <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>
 407 <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>
 408 <div class="line"> </div>
 409 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue1 (<span class="keywordtype">void</span> *argument);         <span class="comment">// thread function 1</span></div>
 410 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue2 (<span class="keywordtype">void</span> *argument);         <span class="comment">// thread function 2</span></div>
 411 <div class="line"> </div>
 412 <div class="line"><span class="keywordtype">int</span> Init_MsgQueue (<span class="keywordtype">void</span>) {</div>
 413 <div class="line"> </div>
 414 <div class="line">  mid_MsgQueue = <a class="code hl_function" href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a>(MSGQUEUE_OBJECTS, <span class="keyword">sizeof</span>(MSGQUEUE_OBJ_t), NULL);</div>
 415 <div class="line">  <span class="keywordflow">if</span> (mid_MsgQueue == NULL) {</div>
 416 <div class="line">    ; <span class="comment">// Message Queue object not created, handle failure</span></div>
 417 <div class="line">  }</div>
 418 <div class="line"> </div>
 419 <div class="line">  tid_Thread_MsgQueue1 = <a class="code hl_function" href="group__CMSIS__RTOS__ThreadMgmt.html#ga48d68b8666d99d28fa646ee1d2182b8f">osThreadNew</a>(Thread_MsgQueue1, NULL, NULL);</div>
 420 <div class="line">  <span class="keywordflow">if</span> (tid_Thread_MsgQueue1 == NULL) {</div>
 421 <div class="line">    <span class="keywordflow">return</span>(-1);</div>
 422 <div class="line">  }</div>
 423 <div class="line">  tid_Thread_MsgQueue2 = <a class="code hl_function" href="group__CMSIS__RTOS__ThreadMgmt.html#ga48d68b8666d99d28fa646ee1d2182b8f">osThreadNew</a>(Thread_MsgQueue2, NULL, NULL);</div>
 424 <div class="line">  <span class="keywordflow">if</span> (tid_Thread_MsgQueue2 == NULL) {</div>
 425 <div class="line">    <span class="keywordflow">return</span>(-1);</div>
 426 <div class="line">  }</div>
 427 <div class="line"> </div>
 428 <div class="line">  <span class="keywordflow">return</span>(0);</div>
 429 <div class="line">}</div>
 430 <div class="line"> </div>
 431 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue1 (<span class="keywordtype">void</span> *argument) {</div>
 432 <div class="line">  MSGQUEUE_OBJ_t msg;</div>
 433 <div class="line"> </div>
 434 <div class="line">  <span class="keywordflow">while</span> (1) {</div>
 435 <div class="line">    ; <span class="comment">// Insert thread code here...</span></div>
 436 <div class="line">    msg.Buf[0] = 0x55U;                                         <span class="comment">// do some work...</span></div>
 437 <div class="line">    msg.Idx    = 0U;</div>
 438 <div class="line">    <a class="code hl_function" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a>(mid_MsgQueue, &amp;msg, 0U, 0U);</div>
 439 <div class="line">    <a class="code hl_function" href="group__CMSIS__RTOS__ThreadMgmt.html#gad01c7ec26535b1de6b018bb9466720e2">osThreadYield</a>();                                            <span class="comment">// suspend thread</span></div>
 440 <div class="line">  }</div>
 441 <div class="line">}</div>
 442 <div class="line"> </div>
 443 <div class="line"><span class="keywordtype">void</span> Thread_MsgQueue2 (<span class="keywordtype">void</span> *argument) {</div>
 444 <div class="line">  MSGQUEUE_OBJ_t msg;</div>
 445 <div class="line">  <a class="code hl_enumeration" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> status;</div>
 446 <div class="line"> </div>
 447 <div class="line">  <span class="keywordflow">while</span> (1) {</div>
 448 <div class="line">    ; <span class="comment">// Insert thread code here...</span></div>
 449 <div class="line">    status = <a class="code hl_function" href="group__CMSIS__RTOS__Message.html#gad90d4959466a7a65105061da8256ab9e">osMessageQueueGet</a>(mid_MsgQueue, &amp;msg, NULL, 0U);   <span class="comment">// wait for message</span></div>
 450 <div class="line">    <span class="keywordflow">if</span> (status == <a class="code hl_enumvalue" href="cmsis__os2_8h.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813ea9e1c9e2550bb4de8969a935acffc968f">osOK</a>) {</div>
 451 <div class="line">      ; <span class="comment">// process data</span></div>
 452 <div class="line">    }</div>
 453 <div class="line">  }</div>
 454 <div class="line">}</div>
 455 <div class="ttc" id="acmsis__os2_8h_html"><div class="ttname"><a href="cmsis__os2_8h.html">cmsis_os2.h</a></div></div>
 456 <div class="ttc" id="acmsis__os2_8h_html_a206dbc05367e03c39fc6d4d1ebcff317"><div class="ttname"><a href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a></div><div class="ttdeci">void * osMessageQueueId_t</div><div class="ttdef"><b>Definition:</b> cmsis_os2.h:271</div></div>
 457 <div class="ttc" id="acmsis__os2_8h_html_ga6c0dbe6069e4e7f47bb4cd32ae2b813ea9e1c9e2550bb4de8969a935acffc968f"><div class="ttname"><a href="cmsis__os2_8h.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813ea9e1c9e2550bb4de8969a935acffc968f">osOK</a></div><div class="ttdeci">@ osOK</div><div class="ttdoc">Operation completed successfully.</div><div class="ttdef"><b>Definition:</b> cmsis_os2.h:240</div></div>
 458 <div class="ttc" id="agroup__CMSIS__RTOS__Definitions_html_ga6c0dbe6069e4e7f47bb4cd32ae2b813e"><div class="ttname"><a href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a></div><div class="ttdeci">osStatus_t</div><div class="ttdoc">Status code values returned by CMSIS-RTOS functions.</div><div class="ttdef"><b>Definition:</b> cmsis_os2.h:239</div></div>
 459 <div class="ttc" id="agroup__CMSIS__RTOS__Message_html_ga24e895a00f9d484db33aaf784c57bfed"><div class="ttname"><a href="group__CMSIS__RTOS__Message.html#ga24e895a00f9d484db33aaf784c57bfed">osMessageQueueNew</a></div><div class="ttdeci">osMessageQueueId_t osMessageQueueNew(uint32_t msg_count, uint32_t msg_size, const osMessageQueueAttr_t *attr)</div><div class="ttdoc">Create and Initialize a Message Queue object.</div></div>
 460 <div class="ttc" id="agroup__CMSIS__RTOS__Message_html_gaa515fc8b956f721a8f72b2c505813bfc"><div class="ttname"><a href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a></div><div class="ttdeci">osStatus_t osMessageQueuePut(osMessageQueueId_t mq_id, const void *msg_ptr, uint8_t msg_prio, uint32_t timeout)</div><div class="ttdoc">Put a Message into a Queue or timeout if Queue is full.</div></div>
 461 <div class="ttc" id="agroup__CMSIS__RTOS__Message_html_gad90d4959466a7a65105061da8256ab9e"><div class="ttname"><a href="group__CMSIS__RTOS__Message.html#gad90d4959466a7a65105061da8256ab9e">osMessageQueueGet</a></div><div class="ttdeci">osStatus_t osMessageQueueGet(osMessageQueueId_t mq_id, void *msg_ptr, uint8_t *msg_prio, uint32_t timeout)</div><div class="ttdoc">Get a Message from a Queue or timeout if Queue is empty.</div></div>
 462 <div class="ttc" id="agroup__CMSIS__RTOS__ThreadMgmt_html_ga48d68b8666d99d28fa646ee1d2182b8f"><div class="ttname"><a href="group__CMSIS__RTOS__ThreadMgmt.html#ga48d68b8666d99d28fa646ee1d2182b8f">osThreadNew</a></div><div class="ttdeci">osThreadId_t osThreadNew(osThreadFunc_t func, void *argument, const osThreadAttr_t *attr)</div><div class="ttdoc">Create a thread and add it to Active Threads.</div></div>
 463 <div class="ttc" id="agroup__CMSIS__RTOS__ThreadMgmt_html_gaa6c32fe2a3e0a2e01f212d55b02e51c7"><div class="ttname"><a href="group__CMSIS__RTOS__ThreadMgmt.html#gaa6c32fe2a3e0a2e01f212d55b02e51c7">osThreadId_t</a></div><div class="ttdeci">void * osThreadId_t</div><div class="ttdef"><b>Definition:</b> cmsis_os2.h:253</div></div>
 464 <div class="ttc" id="agroup__CMSIS__RTOS__ThreadMgmt_html_gad01c7ec26535b1de6b018bb9466720e2"><div class="ttname"><a href="group__CMSIS__RTOS__ThreadMgmt.html#gad01c7ec26535b1de6b018bb9466720e2">osThreadYield</a></div><div class="ttdeci">osStatus_t osThreadYield(void)</div><div class="ttdoc">Pass control to next thread that is in state READY.</div></div>
 465 </div><!-- fragment -->
 466 </div>
 467 </div>
 468 <a id="gad90d4959466a7a65105061da8256ab9e" name="gad90d4959466a7a65105061da8256ab9e"></a>
 469 <h2 class="memtitle"><span class="permalink"><a href="#gad90d4959466a7a65105061da8256ab9e">&#9670;&#160;</a></span>osMessageQueueGet()</h2>
 470
 471 <div class="memitem">
 472 <div class="memproto">
 473       <table class="memname">
 474         <tr>
 475           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueueGet </td>
 476           <td>(</td>
 477           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 478           <td class="paramname"><em>mq_id</em>, </td>
 479         </tr>
 480         <tr>
 481           <td class="paramkey"></td>
 482           <td></td>
 483           <td class="paramtype">void *&#160;</td>
 484           <td class="paramname"><em>msg_ptr</em>, </td>
 485         </tr>
 486         <tr>
 487           <td class="paramkey"></td>
 488           <td></td>
 489           <td class="paramtype">uint8_t *&#160;</td>
 490           <td class="paramname"><em>msg_prio</em>, </td>
 491         </tr>
 492         <tr>
 493           <td class="paramkey"></td>
 494           <td></td>
 495           <td class="paramtype">uint32_t&#160;</td>
 496           <td class="paramname"><em>timeout</em>&#160;</td>
 497         </tr>
 498         <tr>
 499           <td></td>
 500           <td>)</td>
 501           <td></td><td></td>
 502         </tr>
 503       </table>
 504 </div><div class="memdoc">
 505 <dl class="params"><dt>Parameters</dt><dd>
 506   <table class="params">
 507     <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>
 508     <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>
 509     <tr><td class="paramdir">[out]</td><td class="paramname">msg_prio</td><td>pointer to buffer for message priority or NULL. </td></tr>
 510     <tr><td class="paramdir">[in]</td><td class="paramname">timeout</td><td>CMSIS_RTOS_TimeOutValue or 0 in case of no time-out. </td></tr>
 511   </table>
 512   </dd>
 513 </dl>
 514 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 515 <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>
 516 <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 timeout can have the following values:</p><ul>
 517 <li>when <em>timeout</em> is <span class="XML-Token">0</span>, the function returns instantly (i.e. try semantics).</li>
 518 <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>
 519 <li>all other values specify a time in kernel ticks for a timeout (i.e. timed-wait semantics).</li>
 520 </ul>
 521 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 522 <li><em>osOK:</em> the message has been retrieved from the queue.</li>
 523 <li><em>osErrorTimeout:</em> the message could not be retrieved from the queue in the given time (timed-wait semantics).</li>
 524 <li><em>osErrorResource:</em> nothing to get from the queue (try semantics).</li>
 525 <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>
 526 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 527 </ul>
 528 <dl class="section note"><dt>Note</dt><dd>May be called from Interrupt Service Routines if the parameter <em>timeout</em> is set to <span class="XML-Token">0</span>.</dd></dl>
 529 <p><b>Code Example</b></p>
 530 <p>Refer to <a class="el" href="group__CMSIS__RTOS__Message.html#gaa515fc8b956f721a8f72b2c505813bfc">osMessageQueuePut</a> </p>
 531
 532 </div>
 533 </div>
 534 <a id="gac24f87d4f395e9e9c900c320e45ade8a" name="gac24f87d4f395e9e9c900c320e45ade8a"></a>
 535 <h2 class="memtitle"><span class="permalink"><a href="#gac24f87d4f395e9e9c900c320e45ade8a">&#9670;&#160;</a></span>osMessageQueueGetCapacity()</h2>
 536
 537 <div class="memitem">
 538 <div class="memproto">
 539       <table class="memname">
 540         <tr>
 541           <td class="memname">uint32_t osMessageQueueGetCapacity </td>
 542           <td>(</td>
 543           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 544           <td class="paramname"><em>mq_id</em></td><td>)</td>
 545           <td></td>
 546         </tr>
 547       </table>
 548 </div><div class="memdoc">
 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 Interrupt Service Routines. </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"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#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 <dl class="params"><dt>Parameters</dt><dd>
 577   <table class="params">
 578     <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>
 579   </table>
 580   </dd>
 581 </dl>
 582 <dl class="section return"><dt>Returns</dt><dd>maximum message size in bytes.</dd></dl>
 583 <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>
 584 <dl class="section note"><dt>Note</dt><dd>This function may be called from Interrupt Service Routines. </dd></dl>
 585
 586 </div>
 587 </div>
 588 <a id="ga6a32ac394fcff568b251c160cc3014b2" name="ga6a32ac394fcff568b251c160cc3014b2"></a>
 589 <h2 class="memtitle"><span class="permalink"><a href="#ga6a32ac394fcff568b251c160cc3014b2">&#9670;&#160;</a></span>osMessageQueueGetCount()</h2>
 590
 591 <div class="memitem">
 592 <div class="memproto">
 593       <table class="memname">
 594         <tr>
 595           <td class="memname">uint32_t osMessageQueueGetCount </td>
 596           <td>(</td>
 597           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 598           <td class="paramname"><em>mq_id</em></td><td>)</td>
 599           <td></td>
 600         </tr>
 601       </table>
 602 </div><div class="memdoc">
 603 <dl class="params"><dt>Parameters</dt><dd>
 604   <table class="params">
 605     <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>
 606   </table>
 607   </dd>
 608 </dl>
 609 <dl class="section return"><dt>Returns</dt><dd>number of queued messages.</dd></dl>
 610 <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>
 611 <dl class="section note"><dt>Note</dt><dd>This function may be called from Interrupt Service Routines. </dd></dl>
 612
 613 </div>
 614 </div>
 615 <a id="gaddf0904427436dd3880d46263c2dc9fa" name="gaddf0904427436dd3880d46263c2dc9fa"></a>
 616 <h2 class="memtitle"><span class="permalink"><a href="#gaddf0904427436dd3880d46263c2dc9fa">&#9670;&#160;</a></span>osMessageQueueGetSpace()</h2>
 617
 618 <div class="memitem">
 619 <div class="memproto">
 620       <table class="memname">
 621         <tr>
 622           <td class="memname">uint32_t osMessageQueueGetSpace </td>
 623           <td>(</td>
 624           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 625           <td class="paramname"><em>mq_id</em></td><td>)</td>
 626           <td></td>
 627         </tr>
 628       </table>
 629 </div><div class="memdoc">
 630 <dl class="params"><dt>Parameters</dt><dd>
 631   <table class="params">
 632     <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>
 633   </table>
 634   </dd>
 635 </dl>
 636 <dl class="section return"><dt>Returns</dt><dd>number of available slots for messages.</dd></dl>
 637 <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>
 638 <dl class="section note"><dt>Note</dt><dd>This function may be called from Interrupt Service Routines. </dd></dl>
 639
 640 </div>
 641 </div>
 642 <a id="gac6dce7f9ad132d266292c2e979d861b4" name="gac6dce7f9ad132d266292c2e979d861b4"></a>
 643 <h2 class="memtitle"><span class="permalink"><a href="#gac6dce7f9ad132d266292c2e979d861b4">&#9670;&#160;</a></span>osMessageQueueReset()</h2>
 644
 645 <div class="memitem">
 646 <div class="memproto">
 647       <table class="memname">
 648         <tr>
 649           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueueReset </td>
 650           <td>(</td>
 651           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 652           <td class="paramname"><em>mq_id</em></td><td>)</td>
 653           <td></td>
 654         </tr>
 655       </table>
 656 </div><div class="memdoc">
 657 <dl class="params"><dt>Parameters</dt><dd>
 658   <table class="params">
 659     <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>
 660   </table>
 661   </dd>
 662 </dl>
 663 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 664 <p>The function <b>osMessageQueueReset</b> resets the message queue specified by the parameter <em>mq_id</em>.</p>
 665 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 666 <li><em>osOK:</em> the message queue has been rest.</li>
 667 <li><em>osErrorParameter:</em> parameter <em>mq_id</em> is <span class="XML-Token">NULL</span> or invalid.</li>
 668 <li><em>osErrorResource:</em> the message queue is in an invalid state.</li>
 669 <li><em>osErrorISR:</em> <b>osMessageQueueReset</b> cannot be called from interrupt service routines.</li>
 670 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 671 </ul>
 672 <dl class="section note"><dt>Note</dt><dd>This function <b>cannot</b> be called from Interrupt Service Routines. </dd></dl>
 673
 674 </div>
 675 </div>
 676 <a id="gaba987f665444e0d83fa6a3a68bc72abe" name="gaba987f665444e0d83fa6a3a68bc72abe"></a>
 677 <h2 class="memtitle"><span class="permalink"><a href="#gaba987f665444e0d83fa6a3a68bc72abe">&#9670;&#160;</a></span>osMessageQueueDelete()</h2>
 678
 679 <div class="memitem">
 680 <div class="memproto">
 681       <table class="memname">
 682         <tr>
 683           <td class="memname"><a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> osMessageQueueDelete </td>
 684           <td>(</td>
 685           <td class="paramtype"><a class="el" href="cmsis__os2_8h.html#a206dbc05367e03c39fc6d4d1ebcff317">osMessageQueueId_t</a>&#160;</td>
 686           <td class="paramname"><em>mq_id</em></td><td>)</td>
 687           <td></td>
 688         </tr>
 689       </table>
 690 </div><div class="memdoc">
 691 <dl class="params"><dt>Parameters</dt><dd>
 692   <table class="params">
 693     <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>
 694   </table>
 695   </dd>
 696 </dl>
 697 <dl class="section return"><dt>Returns</dt><dd>status code that indicates the execution status of the function.</dd></dl>
 698 <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>
 699 <p>Possible <a class="el" href="group__CMSIS__RTOS__Definitions.html#ga6c0dbe6069e4e7f47bb4cd32ae2b813e">osStatus_t</a> return values:</p><ul>
 700 <li><em>osOK:</em> the message queue object has been deleted.</li>
 701 <li><em>osErrorParameter:</em> parameter <em>mq_id</em> is <span class="XML-Token">NULL</span> or invalid.</li>
 702 <li><em>osErrorResource:</em> the message queue is in an invalid state.</li>
 703 <li><em>osErrorISR:</em> <b>osMessageQueueDelete</b> cannot be called from interrupt service routines.</li>
 704 <li><em>osErrorSafetyClass:</em> the calling thread safety class is lower than the safety class of the specified message queue.</li>
 705 </ul>
 706 <dl class="section note"><dt>Note</dt><dd>This function <b>cannot</b> be called from Interrupt Service Routines. </dd></dl>
 707
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