1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<title>PID Motor Control</title>
<title>CMSIS-DSP: PID Motor Control</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="cmsis.css" rel="stylesheet" type="text/css" />
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<script type="text/javascript" src="printComponentTabs.js"></script>
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript">
$(document).ready(initResizable);
$(window).load(resizeHeight);
</script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/search.js"></script>
<script type="text/javascript">
$(document).ready(function() { searchBox.OnSelectItem(0); });
</script>
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 46px;">
<td id="projectlogo"><img alt="Logo" src="CMSIS_Logo_Final.png"/></td>
<td style="padding-left: 0.5em;">
<div id="projectname">CMSIS-DSP
 <span id="projectnumber">Version 1.7.0</span>
</div>
<div id="projectbrief">CMSIS DSP Software Library</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<div id="CMSISnav" class="tabs1">
<ul class="tablist">
<script type="text/javascript">
<!--
writeComponentTabs.call(this);
//-->
</script>
</ul>
</div>
<!-- Generated by Doxygen 1.8.6 -->
<script type="text/javascript">
var searchBox = new SearchBox("searchBox", "search",false,'Search');
</script>
<div id="navrow1" class="tabs">
<ul class="tablist">
<li><a href="index.html"><span>Main Page</span></a></li>
<li><a href="pages.html"><span>Usage and Description</span></a></li>
<li><a href="modules.html"><span>Reference</span></a></li>
<li>
<div id="MSearchBox" class="MSearchBoxInactive">
<span class="left">
<img id="MSearchSelect" src="search/mag_sel.png"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
alt=""/>
<input type="text" id="MSearchField" value="Search" accesskey="S"
onfocus="searchBox.OnSearchFieldFocus(true)"
onblur="searchBox.OnSearchFieldFocus(false)"
onkeyup="searchBox.OnSearchFieldChange(event)"/>
</span><span class="right">
<a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.png" alt=""/></a>
</span>
</div>
</li>
</ul>
</div>
</div><!-- top -->
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
<div id="nav-sync" class="sync"></div>
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
$(document).ready(function(){initNavTree('group__PID.html','');});
</script>
<div id="doc-content">
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
onkeydown="return searchBox.OnSearchSelectKey(event)">
<a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(0)"><span class="SelectionMark"> </span>All</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(1)"><span class="SelectionMark"> </span>Data Structures</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(2)"><span class="SelectionMark"> </span>Files</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(3)"><span class="SelectionMark"> </span>Functions</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(4)"><span class="SelectionMark"> </span>Variables</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(5)"><span class="SelectionMark"> </span>Typedefs</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(6)"><span class="SelectionMark"> </span>Enumerations</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(7)"><span class="SelectionMark"> </span>Enumerator</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(8)"><span class="SelectionMark"> </span>Macros</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(9)"><span class="SelectionMark"> </span>Groups</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(10)"><span class="SelectionMark"> </span>Pages</a></div>
<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0"
name="MSearchResults" id="MSearchResults">
</iframe>
</div>
<div class="header">
<div class="summary">
<a href="#func-members">Functions</a> </div>
<div class="headertitle">
<div class="title">PID Motor Control<div class="ingroups"><a class="el" href="group__groupController.html">Controller Functions</a></div></div> </div>
</div><!--header-->
<div class="contents">
<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="func-members"></a>
Functions</h2></td></tr>
<tr class="memitem:ga5a6865ed706b7dd969ef0bd58a61f306"><td class="memItemLeft" align="right" valign="top">__STATIC_FORCEINLINE <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#ga5a6865ed706b7dd969ef0bd58a61f306">arm_pid_f32</a> (<a class="el" href="structarm__pid__instance__f32.html">arm_pid_instance_f32</a> *S, <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> in)</td></tr>
<tr class="memdesc:ga5a6865ed706b7dd969ef0bd58a61f306"><td class="mdescLeft"> </td><td class="mdescRight">Process function for the floating-point PID Control. <a href="#ga5a6865ed706b7dd969ef0bd58a61f306">More...</a><br/></td></tr>
<tr class="separator:ga5a6865ed706b7dd969ef0bd58a61f306"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga9ead8b3180125fb42879389477b99dc8"><td class="memItemLeft" align="right" valign="top">__STATIC_FORCEINLINE <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#ga9ead8b3180125fb42879389477b99dc8">arm_pid_q31</a> (<a class="el" href="structarm__pid__instance__q31.html">arm_pid_instance_q31</a> *S, <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> in)</td></tr>
<tr class="memdesc:ga9ead8b3180125fb42879389477b99dc8"><td class="mdescLeft"> </td><td class="mdescRight">Process function for the Q31 PID Control. <a href="#ga9ead8b3180125fb42879389477b99dc8">More...</a><br/></td></tr>
<tr class="separator:ga9ead8b3180125fb42879389477b99dc8"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga7ecc87208cb297fb9a31cec4f18bb54e"><td class="memItemLeft" align="right" valign="top">__STATIC_FORCEINLINE <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#ga7ecc87208cb297fb9a31cec4f18bb54e">arm_pid_q15</a> (<a class="el" href="structarm__pid__instance__q15.html">arm_pid_instance_q15</a> *S, <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> in)</td></tr>
<tr class="memdesc:ga7ecc87208cb297fb9a31cec4f18bb54e"><td class="mdescLeft"> </td><td class="mdescRight">Process function for the Q15 PID Control. <a href="#ga7ecc87208cb297fb9a31cec4f18bb54e">More...</a><br/></td></tr>
<tr class="separator:ga7ecc87208cb297fb9a31cec4f18bb54e"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:gae31536b19b82b93ed184fb1ab73cfcb3"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#gae31536b19b82b93ed184fb1ab73cfcb3">arm_pid_init_f32</a> (<a class="el" href="structarm__pid__instance__f32.html">arm_pid_instance_f32</a> *S, int32_t resetStateFlag)</td></tr>
<tr class="memdesc:gae31536b19b82b93ed184fb1ab73cfcb3"><td class="mdescLeft"> </td><td class="mdescRight">Initialization function for the floating-point PID Control. <a href="#gae31536b19b82b93ed184fb1ab73cfcb3">More...</a><br/></td></tr>
<tr class="separator:gae31536b19b82b93ed184fb1ab73cfcb3"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga2cb1e3d3ebb167348fdabec74653d5c3"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#ga2cb1e3d3ebb167348fdabec74653d5c3">arm_pid_init_q15</a> (<a class="el" href="structarm__pid__instance__q15.html">arm_pid_instance_q15</a> *S, int32_t resetStateFlag)</td></tr>
<tr class="memdesc:ga2cb1e3d3ebb167348fdabec74653d5c3"><td class="mdescLeft"> </td><td class="mdescRight">Initialization function for the Q15 PID Control. <a href="#ga2cb1e3d3ebb167348fdabec74653d5c3">More...</a><br/></td></tr>
<tr class="separator:ga2cb1e3d3ebb167348fdabec74653d5c3"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:gad9d88485234fa9460b1ce9e64989ac86"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#gad9d88485234fa9460b1ce9e64989ac86">arm_pid_init_q31</a> (<a class="el" href="structarm__pid__instance__q31.html">arm_pid_instance_q31</a> *S, int32_t resetStateFlag)</td></tr>
<tr class="memdesc:gad9d88485234fa9460b1ce9e64989ac86"><td class="mdescLeft"> </td><td class="mdescRight">Initialization function for the Q31 PID Control. <a href="#gad9d88485234fa9460b1ce9e64989ac86">More...</a><br/></td></tr>
<tr class="separator:gad9d88485234fa9460b1ce9e64989ac86"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga9ec860bcb6f8ca31205bf0f1b51ab723"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#ga9ec860bcb6f8ca31205bf0f1b51ab723">arm_pid_reset_f32</a> (<a class="el" href="structarm__pid__instance__f32.html">arm_pid_instance_f32</a> *S)</td></tr>
<tr class="memdesc:ga9ec860bcb6f8ca31205bf0f1b51ab723"><td class="mdescLeft"> </td><td class="mdescRight">Reset function for the floating-point PID Control. <a href="#ga9ec860bcb6f8ca31205bf0f1b51ab723">More...</a><br/></td></tr>
<tr class="separator:ga9ec860bcb6f8ca31205bf0f1b51ab723"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga408566dacb4fa6e0458b2c75672e525f"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#ga408566dacb4fa6e0458b2c75672e525f">arm_pid_reset_q15</a> (<a class="el" href="structarm__pid__instance__q15.html">arm_pid_instance_q15</a> *S)</td></tr>
<tr class="memdesc:ga408566dacb4fa6e0458b2c75672e525f"><td class="mdescLeft"> </td><td class="mdescRight">Reset function for the Q15 PID Control. <a href="#ga408566dacb4fa6e0458b2c75672e525f">More...</a><br/></td></tr>
<tr class="separator:ga408566dacb4fa6e0458b2c75672e525f"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:gaeecbacd3fb37c608ec25474d3a0dffa9"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__PID.html#gaeecbacd3fb37c608ec25474d3a0dffa9">arm_pid_reset_q31</a> (<a class="el" href="structarm__pid__instance__q31.html">arm_pid_instance_q31</a> *S)</td></tr>
<tr class="memdesc:gaeecbacd3fb37c608ec25474d3a0dffa9"><td class="mdescLeft"> </td><td class="mdescRight">Reset function for the Q31 PID Control. <a href="#gaeecbacd3fb37c608ec25474d3a0dffa9">More...</a><br/></td></tr>
<tr class="separator:gaeecbacd3fb37c608ec25474d3a0dffa9"><td class="memSeparator" colspan="2"> </td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Description</h2>
<p>A Proportional Integral Derivative (PID) controller is a generic feedback control loop mechanism widely used in industrial control systems. A PID controller is the most commonly used type of feedback controller.</p>
<p>This set of functions implements (PID) controllers for Q15, Q31, and floating-point data types. The functions operate on a single sample of data and each call to the function returns a single processed value. <code>S</code> points to an instance of the PID control data structure. <code>in</code> is the input sample value. The functions return the output value.</p>
<dl class="section user"><dt>Algorithm:</dt><dd><pre>
y[n] = y[n-1] + A0 * x[n] + A1 * x[n-1] + A2 * x[n-2]
A0 = Kp + Ki + Kd
A1 = (-Kp ) - (2 * Kd )
A2 = Kd
</pre></dd></dl>
<dl class="section user"><dt></dt><dd>where <code>Kp</code> is proportional constant, <code>Ki</code> is Integral constant and <code>Kd</code> is Derivative constant</dd></dl>
<dl class="section user"><dt></dt><dd><div class="image">
<img src="PID.gif" alt="PID.gif"/>
<div class="caption">
Proportional Integral Derivative Controller</div></div>
</dd></dl>
<dl class="section user"><dt></dt><dd>The PID controller calculates an "error" value as the difference between the measured output and the reference input. The controller attempts to minimize the error by adjusting the process control inputs. The proportional value determines the reaction to the current error, the integral value determines the reaction based on the sum of recent errors, and the derivative value determines the reaction based on the rate at which the error has been changing.</dd></dl>
<dl class="section user"><dt>Instance Structure</dt><dd>The Gains A0, A1, A2 and state variables for a PID controller are stored together in an instance data structure. A separate instance structure must be defined for each PID Controller. There are separate instance structure declarations for each of the 3 supported data types.</dd></dl>
<dl class="section user"><dt>Reset Functions</dt><dd>There is also an associated reset function for each data type which clears the state array.</dd></dl>
<dl class="section user"><dt>Initialization Functions</dt><dd>There is also an associated initialization function for each data type. The initialization function performs the following operations:<ul>
<li>Initializes the Gains A0, A1, A2 from Kp,Ki, Kd gains.</li>
<li>Zeros out the values in the state buffer.</li>
</ul>
</dd></dl>
<dl class="section user"><dt></dt><dd>Instance structure cannot be placed into a const data section and it is recommended to use the initialization function.</dd></dl>
<dl class="section user"><dt>Fixed-Point Behavior</dt><dd>Care must be taken when using the fixed-point versions of the PID Controller functions. In particular, the overflow and saturation behavior of the accumulator used in each function must be considered. Refer to the function specific documentation below for usage guidelines. </dd></dl>
<h2 class="groupheader">Function Documentation</h2>
<a class="anchor" id="ga5a6865ed706b7dd969ef0bd58a61f306"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">__STATIC_FORCEINLINE <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> arm_pid_f32 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__f32.html">arm_pid_instance_f32</a> * </td>
<td class="paramname"><em>S</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> </td>
<td class="paramname"><em>in</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>is an instance of the floating-point PID Control structure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">in</td><td>input sample to process </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>processed output sample. </dd></dl>
</div>
</div>
<a class="anchor" id="gae31536b19b82b93ed184fb1ab73cfcb3"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void arm_pid_init_f32 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__f32.html">arm_pid_instance_f32</a> * </td>
<td class="paramname"><em>S</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int32_t </td>
<td class="paramname"><em>resetStateFlag</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the PID structure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">resetStateFlag</td><td><ul>
<li>value = 0: no change in state</li>
<li>value = 1: reset state </li>
</ul>
</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>none</dd></dl>
<dl class="section user"><dt>Details</dt><dd>The <code>resetStateFlag</code> specifies whether to set state to zero or not. <br/>
The function computes the structure fields: <code>A0</code>, <code>A1</code> <code>A2</code> using the proportional gain( <code>Kp</code>), integral gain( <code>Ki</code>) and derivative gain( <code>Kd</code>) also sets the state variables to all zeros. </dd></dl>
</div>
</div>
<a class="anchor" id="ga2cb1e3d3ebb167348fdabec74653d5c3"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void arm_pid_init_q15 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__q15.html">arm_pid_instance_q15</a> * </td>
<td class="paramname"><em>S</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int32_t </td>
<td class="paramname"><em>resetStateFlag</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the Q15 PID structure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">resetStateFlag</td><td><ul>
<li>value = 0: no change in state</li>
<li>value = 1: reset state </li>
</ul>
</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>none</dd></dl>
<dl class="section user"><dt>Details</dt><dd>The <code>resetStateFlag</code> specifies whether to set state to zero or not. <br/>
The function computes the structure fields: <code>A0</code>, <code>A1</code> <code>A2</code> using the proportional gain( <code>Kp</code>), integral gain( <code>Ki</code>) and derivative gain( <code>Kd</code>) also sets the state variables to all zeros. </dd></dl>
</div>
</div>
<a class="anchor" id="gad9d88485234fa9460b1ce9e64989ac86"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void arm_pid_init_q31 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__q31.html">arm_pid_instance_q31</a> * </td>
<td class="paramname"><em>S</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int32_t </td>
<td class="paramname"><em>resetStateFlag</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the Q31 PID structure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">resetStateFlag</td><td><ul>
<li>value = 0: no change in state</li>
<li>value = 1: reset state </li>
</ul>
</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>none</dd></dl>
<dl class="section user"><dt>Details</dt><dd>The <code>resetStateFlag</code> specifies whether to set state to zero or not. <br/>
The function computes the structure fields: <code>A0</code>, <code>A1</code> <code>A2</code> using the proportional gain( <code>Kp</code>), integral gain( <code>Ki</code>) and derivative gain( <code>Kd</code>) also sets the state variables to all zeros. </dd></dl>
</div>
</div>
<a class="anchor" id="ga7ecc87208cb297fb9a31cec4f18bb54e"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">__STATIC_FORCEINLINE <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> arm_pid_q15 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__q15.html">arm_pid_instance_q15</a> * </td>
<td class="paramname"><em>S</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> </td>
<td class="paramname"><em>in</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the Q15 PID Control structure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">in</td><td>input sample to process </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>processed output sample.</dd></dl>
<dl class="section user"><dt>Scaling and Overflow Behavior</dt><dd>The function is implemented using a 64-bit internal accumulator. Both Gains and state variables are represented in 1.15 format and multiplications yield a 2.30 result. The 2.30 intermediate results are accumulated in a 64-bit accumulator in 34.30 format. There is no risk of internal overflow with this approach and the full precision of intermediate multiplications is preserved. After all additions have been performed, the accumulator is truncated to 34.15 format by discarding low 15 bits. Lastly, the accumulator is saturated to yield a result in 1.15 format. </dd></dl>
</div>
</div>
<a class="anchor" id="ga9ead8b3180125fb42879389477b99dc8"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">__STATIC_FORCEINLINE <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> arm_pid_q31 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__q31.html">arm_pid_instance_q31</a> * </td>
<td class="paramname"><em>S</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> </td>
<td class="paramname"><em>in</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the Q31 PID Control structure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">in</td><td>input sample to process </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>processed output sample.</dd></dl>
<dl class="section user"><dt>Scaling and Overflow Behavior</dt><dd>The function is implemented using an internal 64-bit accumulator. The accumulator has a 2.62 format and maintains full precision of the intermediate multiplication results but provides only a single guard bit. Thus, if the accumulator result overflows it wraps around rather than clip. In order to avoid overflows completely the input signal must be scaled down by 2 bits as there are four additions. After all multiply-accumulates are performed, the 2.62 accumulator is truncated to 1.32 format and then saturated to 1.31 format. </dd></dl>
</div>
</div>
<a class="anchor" id="ga9ec860bcb6f8ca31205bf0f1b51ab723"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void arm_pid_reset_f32 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__f32.html">arm_pid_instance_f32</a> * </td>
<td class="paramname"><em>S</em></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the floating-point PID structure </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>none</dd></dl>
<dl class="section user"><dt>Details</dt><dd>The function resets the state buffer to zeros. </dd></dl>
</div>
</div>
<a class="anchor" id="ga408566dacb4fa6e0458b2c75672e525f"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void arm_pid_reset_q15 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__q15.html">arm_pid_instance_q15</a> * </td>
<td class="paramname"><em>S</em></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the Q15 PID structure </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>none</dd></dl>
<dl class="section user"><dt>Details</dt><dd>The function resets the state buffer to zeros. </dd></dl>
</div>
</div>
<a class="anchor" id="gaeecbacd3fb37c608ec25474d3a0dffa9"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void arm_pid_reset_q31 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structarm__pid__instance__q31.html">arm_pid_instance_q31</a> * </td>
<td class="paramname"><em>S</em></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">S</td><td>points to an instance of the Q31 PID structure </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>none</dd></dl>
<dl class="section user"><dt>Details</dt><dd>The function resets the state buffer to zeros. </dd></dl>
</div>
</div>
</div><!-- contents -->
</div><!-- doc-content -->
<!-- start footer part -->
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="footer">Generated on Wed Jul 10 2019 15:20:39 for CMSIS-DSP Version 1.7.0 by Arm Ltd. All rights reserved.
<!--
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.8.6
-->
</li>
</ul>
</div>
</body>
</html>
|
