speed__cntr_8c.html

使用AVR单片机控制步进电机的软件代码

00132     OCR1A = 10;
00133     <span class="comment">// Set Timer/Counter to divide clock by 8</span>
00134     TCCR1B |= ((0&lt;&lt;CS12)|(1&lt;&lt;CS11)|(0&lt;&lt;CS10));
00135   }
00136 }
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<a class="anchor" name="a3" doxytag="speed_cntr.c::speed_cntr_TIMER1_COMPA_interrupt" ></a><p>
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          <td class="md" nowrap valign="top"> __interrupt void speed_cntr_TIMER1_COMPA_interrupt           </td>
          <td class="md" valign="top">(&nbsp;</td>
          <td class="md" nowrap valign="top">void&nbsp;</td>
          <td class="mdname1" valign="top" nowrap>          </td>
          <td class="md" valign="top">&nbsp;)&nbsp;</td>
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<p>
Timer/Counter1 Output Compare A Match Interrupt. 
<p>
Timer/Counter1 Output Compare A Match Interrupt. Increments/decrements the position of the stepper motor exept after last position, when it stops. The step_delay defines the period of this interrupt and controls the speed of the stepper motor. A new step delay is calculated to follow wanted speed profile on basis of accel/decel parameters. 
<p>
Definition at line <a class="el" href="speed__cntr_8c-source.html#l00164">164</a> of file <a class="el" href="speed__cntr_8c-source.html">speed_cntr.c</a>.
<p>
References <a class="el" href="speed__cntr_8h-source.html#l00081">ACCEL</a>, <a class="el" href="speed__cntr_8h-source.html#l00044">speedRampData::accel_count</a>, <a class="el" href="speed__cntr_8h-source.html#l00082">DECEL</a>, <a class="el" href="speed__cntr_8h-source.html#l00038">speedRampData::decel_start</a>, <a class="el" href="speed__cntr_8h-source.html#l00040">speedRampData::decel_val</a>, <a class="el" href="speed__cntr_8h-source.html#l00034">speedRampData::dir</a>, <a class="el" href="global_8h-source.html#l00025">FALSE</a>, <a class="el" href="speed__cntr_8h-source.html#l00042">speedRampData::min_delay</a>, <a class="el" href="speed__cntr_8h-source.html#l00083">RUN</a>, <a class="el" href="speed__cntr_8h-source.html#l00032">speedRampData::run_state</a>, <a class="el" href="global_8h-source.html#l00031">GLOBAL_FLAGS::running</a>, <a class="el" href="sm__driver_8c-source.html#l00066">sm_driver_StepCounter()</a>, <a class="el" href="speed__cntr_8c-source.html#l00031">srd</a>, <a class="el" href="main_8c-source.html#l00033">status</a>, <a class="el" href="speed__cntr_8h-source.html#l00036">speedRampData::step_delay</a>, and <a class="el" href="speed__cntr_8h-source.html#l00080">STOP</a>.
<p>
<pre class="fragment"><div>00165 {
00166   <span class="comment">// Holds next delay period.</span>
00167   <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> new_step_delay;
00168   <span class="comment">// Remember the last step delay used when accelrating.</span>
00169   <span class="keyword">static</span> <span class="keywordtype">int</span> last_accel_delay;
00170   <span class="comment">// Counting steps when moving.</span>
00171   <span class="keyword">static</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> step_count = 0;
00172   <span class="comment">// Keep track of remainder from new_step-delay calculation to incrase accurancy</span>
00173   <span class="keyword">static</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> rest = 0;
00174 
00175   OCR1A = <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a>;
00176 
00177   <span class="keywordflow">switch</span>(<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o5">run_state</a>) {
00178     <span class="keywordflow">case</span> <a class="code" href="speed__cntr_8h.html#a7">STOP</a>:
00179       step_count = 0;
00180       rest = 0;
00181       <span class="comment">// Stop Timer/Counter 1.</span>
00182       TCCR1B &amp;= ~((1&lt;&lt;CS12)|(1&lt;&lt;CS11)|(1&lt;&lt;CS10));
00183       <a class="code" href="main_8c.html#a0">status</a>.<a class="code" href="structGLOBAL__FLAGS.html#o2">running</a> = <a class="code" href="global_8h.html#a1">FALSE</a>;
00184       <span class="keywordflow">break</span>;
00185 
00186     <span class="keywordflow">case</span> <a class="code" href="speed__cntr_8h.html#a8">ACCEL</a>:
00187       <a class="code" href="sm__driver_8h.html#a11">sm_driver_StepCounter</a>(<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o3">dir</a>);
00188       step_count++;
00189       <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a>++;
00190       new_step_delay = <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a> - (((2 * (<span class="keywordtype">long</span>)<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a>) + rest)/(4 * <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a> + 1));
00191       rest = ((2 * (<span class="keywordtype">long</span>)<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a>)+rest)%(4 * <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a> + 1);
00192       <span class="comment">// Chech if we should start decelration.</span>
00193       <span class="keywordflow">if</span>(step_count &gt;= <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o1">decel_start</a>) {
00194         <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a> = <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o2">decel_val</a>;
00195         <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o5">run_state</a> = <a class="code" href="speed__cntr_8h.html#a9">DECEL</a>;
00196       }
00197       <span class="comment">// Chech if we hitted max speed.</span>
00198       <span class="keywordflow">else</span> <span class="keywordflow">if</span>(new_step_delay &lt;= <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o4">min_delay</a>) {
00199         last_accel_delay = new_step_delay;
00200         new_step_delay = <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o4">min_delay</a>;
00201         rest = 0;
00202         <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o5">run_state</a> = <a class="code" href="speed__cntr_8h.html#a10">RUN</a>;
00203       }
00204       <span class="keywordflow">break</span>;
00205 
00206     <span class="keywordflow">case</span> <a class="code" href="speed__cntr_8h.html#a10">RUN</a>:
00207       <a class="code" href="sm__driver_8h.html#a11">sm_driver_StepCounter</a>(<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o3">dir</a>);
00208       step_count++;
00209       new_step_delay = <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o4">min_delay</a>;
00210       <span class="comment">// Chech if we should start decelration.</span>
00211       <span class="keywordflow">if</span>(step_count &gt;= <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o1">decel_start</a>) {
00212         <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a> = <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o2">decel_val</a>;
00213         <span class="comment">// Start decelration with same delay as accel ended with.</span>
00214         new_step_delay = last_accel_delay;
00215         <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o5">run_state</a> = <a class="code" href="speed__cntr_8h.html#a9">DECEL</a>;
00216       }
00217       <span class="keywordflow">break</span>;
00218 
00219     <span class="keywordflow">case</span> <a class="code" href="speed__cntr_8h.html#a9">DECEL</a>:
00220       <a class="code" href="sm__driver_8h.html#a11">sm_driver_StepCounter</a>(<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o3">dir</a>);
00221       step_count++;
00222       <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a>++;
00223       new_step_delay = <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a> - (((2 * (<span class="keywordtype">long</span>)<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a>) + rest)/(4 * <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a> + 1));
00224       rest = ((2 * (<span class="keywordtype">long</span>)<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a>)+rest)%(4 * <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a> + 1);
00225       <span class="comment">// Check if we at last step</span>
00226       <span class="keywordflow">if</span>(<a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o0">accel_count</a> &gt;= 0){
00227         <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o5">run_state</a> = <a class="code" href="speed__cntr_8h.html#a7">STOP</a>;
00228       }
00229       <span class="keywordflow">break</span>;
00230   }
00231   <a class="code" href="speed__cntr_8c.html#a0">srd</a>.<a class="code" href="structspeedRampData.html#o6">step_delay</a> = new_step_delay;
00232 }
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<p>
Here is the call graph for this function:<p><center><img src="speed__cntr_8c_a3_cgraph.png" border="0" usemap="#speed__cntr_8c_a3_cgraph_map" alt=""></center>
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<area href="sm__driver_8h.html#a11" shape="rect" coords="315,7,478,33" alt="">
<area href="sm__driver_8h.html#a12" shape="rect" coords="527,7,684,33" alt="">
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<hr><h2>Variable Documentation</h2>
<a class="anchor" name="a0" doxytag="speed_cntr.c::srd" ></a><p>
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          <td class="md" nowrap valign="top"> <a class="el" href="structspeedRampData.html">speedRampData</a> <a class="el" href="speed__cntr_8c.html#a0">srd</a>          </td>
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<p>
Cointains data for timer interrupt. 
<p>

<p>
Definition at line <a class="el" href="speed__cntr_8c-source.html#l00031">31</a> of file <a class="el" href="speed__cntr_8c-source.html">speed_cntr.c</a>.
<p>
Referenced by <a class="el" href="speed__cntr_8c-source.html#l00143">speed_cntr_Init_Timer1()</a>, <a class="el" href="speed__cntr_8c-source.html#l00046">speed_cntr_Move()</a>, and <a class="el" href="speed__cntr_8c-source.html#l00164">speed_cntr_TIMER1_COMPA_interrupt()</a>.    </td>
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<hr size="1"><address style="align: right;"><small>Generated on Mon May 8 15:05:04 2006 for AVR446 - Linear speed control of stepper motor by
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