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style="mso-spacerun: yes"> </span>The maximum </span><b><span lang=EN-US
style='font-family:"Courier New"'>timeout</span></b><span lang=EN-US> is 65535
clock ticks.<span style="mso-spacerun: yes"> </span>The timeout value is
not synchronized with the clock tick.<span style="mso-spacerun: yes">
</span>The timeout count starts being decremented on the next clock tick which
could potentially occur immediately.</span></p>
<p class=Descript><b><span lang=EN-US style='font-family:"Courier New"'>err</span></b><span
lang=EN-US> is a pointer to a variable which will be used to hold an error
code.<span style="mso-spacerun: yes"> </span></span><b><span lang=EN-US
style='font-family:"Courier New"'>OSMboxPend()</span></b><span lang=EN-US> sets
</span><b><span lang=EN-US style='font-family:"Courier New"'>*err</span></b><span
lang=EN-US> to either:</span></p>
<p class=Descript style='margin-left:54.0pt;text-indent:-18.0pt'><span
lang=EN-US>1) <span style='mso-tab-count:1'> </span></span><b><span
lang=EN-US style='font-family:"Courier New"'>OS_NO_ERR</span></b><span
lang=EN-US>, a message was received</span></p>
<p class=Descript style='margin-left:54.0pt;text-indent:-18.0pt'><span
lang=EN-US>2) <span style='mso-tab-count:1'> </span></span><b><span
lang=EN-US style='font-family:"Courier New"'>OS_TIMEOUT</span></b><span
lang=EN-US>, a message was not received within the specified timeout period</span></p>
<p class=Descript style='margin-left:54.0pt;text-indent:-18.0pt'><span
lang=EN-US>3) <span style='mso-tab-count:1'> </span></span><b><span
lang=EN-US style='font-family:"Courier New"'>OS_ERR_PEND_ISR</span></b><span
lang=EN-US>, you called this function from an ISR and µC/OS-II would have to
suspend the ISR.<span style="mso-spacerun: yes"> </span>In general, you
should not call </span><b><span lang=EN-US style='font-family:"Courier New"'>OSMboxPend()</span></b><span
lang=EN-US>.<span style="mso-spacerun: yes"> </span>µC/OS-II checks for
this situation in case you do anyway. </span></p>
<p class=Descript><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
<p class=NewSectionPara><b><span lang=EN-US>Returned Value<o:p></o:p></span></b></p>
<p class=Descript><b><span lang=EN-US style='font-family:"Courier New"'>OSMboxPend()</span></b><span
lang=EN-US> returns the message sent by either a task or an ISR and </span><b><span
lang=EN-US style='font-family:"Courier New"'>*err</span></b><span lang=EN-US>
is set to </span><b><span lang=EN-US style='font-family:"Courier New"'>OS_NO_ERR</span></b><span
lang=EN-US>.<span style="mso-spacerun: yes"> </span>If a message is not
received within the specified timeout period, the returned message will be a </span><b><span
lang=EN-US style='font-family:"Courier New"'>NULL</span></b><span lang=EN-US>
pointer and </span><b><span lang=EN-US style='font-family:"Courier New"'>*err</span></b><span
lang=EN-US> is set to </span><b><span lang=EN-US style='font-family:"Courier New"'>OS_TIMEOUT</span></b><span
lang=EN-US>.</span></p>
<p class=NewSectionPara><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
<p class=NewSectionPara><b><span lang=EN-US>Notes/Warnings<o:p></o:p></span></b></p>
<p class=Descript><span lang=EN-US>Mailboxes must be created before they are
used. </span></p>
<p class=Descript><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
<b><span lang=EN-US style='font-size:10.0pt;mso-bidi-font-size:12.0pt;
font-family:"Times New Roman";mso-fareast-font-family:宋体;mso-ansi-language:
EN-US;mso-fareast-language:RU;mso-bidi-language:AR-SA'><br clear=all
style='page-break-before:always'>
</span></b>
<p class=NewSectionPara><b><span lang=EN-US>Example<o:p></o:p></span></b></p>
<div style='border:solid #999999 1.5pt;padding:1.0pt 1.0pt 15.0pt 1.0pt;
background:#F2F2F2;mso-shading:windowtext;mso-pattern:gray-5 auto'>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style='mso-tab-count:1'> </span>OS_EVENT *CommMbox;</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style='mso-tab-count:1'> </span>void CommTask(void *pdata)</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style='mso-tab-count:1'> </span>{</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes"> </span>INT8U<span
style="mso-spacerun: yes"> </span>err;</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes"> </span>void<span
style="mso-spacerun: yes"> </span>*msg;</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes"> </span>pdata = pdata;</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes"> </span>for (;;) {</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes">
</span>.</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style='mso-tab-count:3'> </span>.</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style='mso-tab-count:3'> </span>msg
= OSMboxPend(CommMbox, 10, &err);</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes">
</span>if (err == OS_NO_ERR) {</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun:
yes">
</span>.</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun:
yes">
</span>.<span style="mso-spacerun: yes"> </span>/* Code for received
message<span style="mso-spacerun: yes">
</span>*/<span style="mso-spacerun:
yes"> </span></span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun:
yes">
</span>.</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes">
</span>} else {</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun:
yes">
</span>.</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun:
yes">
</span>.<span style="mso-spacerun: yes"> </span>/* Code for message not
received within timeout */</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun:
yes">
</span>.</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes">
</span>} </span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes"> </span><span
style="mso-spacerun: yes"> </span>.<span style="mso-spacerun:
yes"> </span></span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style='mso-tab-count:3'> </span>.</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style="mso-spacerun: yes"> </span>}</span></p>
<p class=CodeSeg style='border:none;mso-border-alt:solid #999999 1.5pt;
padding:0cm;mso-padding-alt:1.0pt 1.0pt 15.0pt 1.0pt'><span lang=EN-US><span
style='mso-tab-count:1'> </span>}</span></p>
</div>
</div>
<span lang=EN-US style='font-size:10.5pt;mso-bidi-font-size:12.0pt;font-family:
"Times New Roman";mso-fareast-font-family:宋体;mso-font-kerning:1.0pt;mso-ansi-language:
EN-US;mso-fareast-language:ZH-CN;mso-bidi-language:AR-SA'><br clear=all
style='page-break-before:always;mso-break-type:section-break'>
</span>
<div class=Section2 style='layout-grid:15.6pt'>
<p class=MsoNormal><span lang=EN-US><![if !supportEmptyParas]> <![endif]><o:p></o:p></span></p>
</div>
</body>
</html>
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