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49 <div class="headertitle">
50 <h1>arm_fir_interpolate_f32.c</h1> </div>
52 <div class="contents">
53 <a href="arm__fir__interpolate__f32_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/* ---------------------------------------------------------------------- </span>
54 <a name="l00002"></a>00002 <span class="comment">* Copyright (C) 2010 ARM Limited. All rights reserved. </span>
55 <a name="l00003"></a>00003 <span class="comment">* </span>
56 <a name="l00004"></a>00004 <span class="comment">* $Date: 15. July 2011 </span>
57 <a name="l00005"></a>00005 <span class="comment">* $Revision: V1.0.10 </span>
58 <a name="l00006"></a>00006 <span class="comment">* </span>
59 <a name="l00007"></a>00007 <span class="comment">* Project: CMSIS DSP Library </span>
60 <a name="l00008"></a>00008 <span class="comment">* Title: arm_fir_interpolate_f32.c </span>
61 <a name="l00009"></a>00009 <span class="comment">* </span>
62 <a name="l00010"></a>00010 <span class="comment">* Description: FIR interpolation for floating-point sequences. </span>
63 <a name="l00011"></a>00011 <span class="comment">* </span>
64 <a name="l00012"></a>00012 <span class="comment">* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0</span>
65 <a name="l00013"></a>00013 <span class="comment">* </span>
66 <a name="l00014"></a>00014 <span class="comment">* Version 1.0.10 2011/7/15 </span>
67 <a name="l00015"></a>00015 <span class="comment">* Big Endian support added and Merged M0 and M3/M4 Source code. </span>
68 <a name="l00016"></a>00016 <span class="comment">* </span>
69 <a name="l00017"></a>00017 <span class="comment">* Version 1.0.3 2010/11/29 </span>
70 <a name="l00018"></a>00018 <span class="comment">* Re-organized the CMSIS folders and updated documentation. </span>
71 <a name="l00019"></a>00019 <span class="comment">* </span>
72 <a name="l00020"></a>00020 <span class="comment">* Version 1.0.2 2010/11/11 </span>
73 <a name="l00021"></a>00021 <span class="comment">* Documentation updated. </span>
74 <a name="l00022"></a>00022 <span class="comment">* </span>
75 <a name="l00023"></a>00023 <span class="comment">* Version 1.0.1 2010/10/05 </span>
76 <a name="l00024"></a>00024 <span class="comment">* Production release and review comments incorporated. </span>
77 <a name="l00025"></a>00025 <span class="comment">* </span>
78 <a name="l00026"></a>00026 <span class="comment">* Version 1.0.0 2010/09/20 </span>
79 <a name="l00027"></a>00027 <span class="comment">* Production release and review comments incorporated </span>
80 <a name="l00028"></a>00028 <span class="comment">* </span>
81 <a name="l00029"></a>00029 <span class="comment">* Version 0.0.7 2010/06/10 </span>
82 <a name="l00030"></a>00030 <span class="comment">* Misra-C changes done </span>
83 <a name="l00031"></a>00031 <span class="comment">* -------------------------------------------------------------------- */</span>
84 <a name="l00032"></a>00032
85 <a name="l00033"></a>00033 <span class="preprocessor">#include "<a class="code" href="arm__math_8h.html">arm_math.h</a>"</span>
86 <a name="l00034"></a>00034
87 <a name="l00135"></a><a class="code" href="group___f_i_r___interpolate.html#ga9cae104c5cf60b4e7671c82264a8c12e">00135</a> <span class="keywordtype">void</span> <a class="code" href="group___f_i_r___interpolate.html#ga9cae104c5cf60b4e7671c82264a8c12e" title="Processing function for the floating-point FIR interpolator.">arm_fir_interpolate_f32</a>(
88 <a name="l00136"></a>00136 <span class="keyword">const</span> <a class="code" href="structarm__fir__interpolate__instance__f32.html" title="Instance structure for the floating-point FIR interpolator.">arm_fir_interpolate_instance_f32</a> * S,
89 <a name="l00137"></a>00137 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> * pSrc,
90 <a name="l00138"></a>00138 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> * pDst,
91 <a name="l00139"></a>00139 uint32_t <a class="code" href="arm__fir__example__f32_8c.html#ab6558f40a619c2502fbc24c880fd4fb0">blockSize</a>)
92 <a name="l00140"></a>00140 {
93 <a name="l00141"></a>00141 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> *pState = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a42a8ba1bda85fa86d7b6c84d3da4c75b">pState</a>; <span class="comment">/* State pointer */</span>
94 <a name="l00142"></a>00142 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> *pCoeffs = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a86053b715980a93c9df630d6de5bb63c">pCoeffs</a>; <span class="comment">/* Coefficient pointer */</span>
95 <a name="l00143"></a>00143 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> *pStateCurnt; <span class="comment">/* Points to the current sample of the state */</span>
96 <a name="l00144"></a>00144 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> *ptr1, *ptr2; <span class="comment">/* Temporary pointers for state and coefficient buffers */</span>
97 <a name="l00145"></a>00145
98 <a name="l00146"></a>00146
99 <a name="l00147"></a>00147 <span class="preprocessor">#ifndef ARM_MATH_CM0</span>
100 <a name="l00148"></a>00148 <span class="preprocessor"></span>
101 <a name="l00149"></a>00149 <span class="comment">/* Run the below code for Cortex-M4 and Cortex-M3 */</span>
102 <a name="l00150"></a>00150
103 <a name="l00151"></a>00151 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> sum0; <span class="comment">/* Accumulators */</span>
104 <a name="l00152"></a>00152 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> x0, c0; <span class="comment">/* Temporary variables to hold state and coefficient values */</span>
105 <a name="l00153"></a>00153 uint32_t i, blkCnt, j; <span class="comment">/* Loop counters */</span>
106 <a name="l00154"></a>00154 uint16_t phaseLen = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a389e669e13ec56292a70db8e92194b12">phaseLength</a>, tapCnt; <span class="comment">/* Length of each polyphase filter component */</span>
107 <a name="l00155"></a>00155
108 <a name="l00156"></a>00156
109 <a name="l00157"></a>00157 <span class="comment">/* S->pState buffer contains previous frame (phaseLen - 1) samples */</span>
110 <a name="l00158"></a>00158 <span class="comment">/* pStateCurnt points to the location where the new input data should be written */</span>
111 <a name="l00159"></a>00159 pStateCurnt = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a42a8ba1bda85fa86d7b6c84d3da4c75b">pState</a> + (phaseLen - 1u);
112 <a name="l00160"></a>00160
113 <a name="l00161"></a>00161 <span class="comment">/* Total number of intput samples */</span>
114 <a name="l00162"></a>00162 blkCnt = <a class="code" href="arm__fir__example__f32_8c.html#ab6558f40a619c2502fbc24c880fd4fb0">blockSize</a>;
115 <a name="l00163"></a>00163
116 <a name="l00164"></a>00164 <span class="comment">/* Loop over the blockSize. */</span>
117 <a name="l00165"></a>00165 <span class="keywordflow">while</span>(blkCnt > 0u)
118 <a name="l00166"></a>00166 {
119 <a name="l00167"></a>00167 <span class="comment">/* Copy new input sample into the state buffer */</span>
120 <a name="l00168"></a>00168 *pStateCurnt++ = *pSrc++;
121 <a name="l00169"></a>00169
122 <a name="l00170"></a>00170 <span class="comment">/* Address modifier index of coefficient buffer */</span>
123 <a name="l00171"></a>00171 j = 1u;
124 <a name="l00172"></a>00172
125 <a name="l00173"></a>00173 <span class="comment">/* Loop over the Interpolation factor. */</span>
126 <a name="l00174"></a>00174 i = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
127 <a name="l00175"></a>00175 <span class="keywordflow">while</span>(i > 0u)
128 <a name="l00176"></a>00176 {
129 <a name="l00177"></a>00177 <span class="comment">/* Set accumulator to zero */</span>
130 <a name="l00178"></a>00178 sum0 = 0.0f;
131 <a name="l00179"></a>00179
132 <a name="l00180"></a>00180 <span class="comment">/* Initialize state pointer */</span>
133 <a name="l00181"></a>00181 ptr1 = pState;
134 <a name="l00182"></a>00182
135 <a name="l00183"></a>00183 <span class="comment">/* Initialize coefficient pointer */</span>
136 <a name="l00184"></a>00184 ptr2 = pCoeffs + (S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a> - j);
137 <a name="l00185"></a>00185
138 <a name="l00186"></a>00186 <span class="comment">/* Loop over the polyPhase length. Unroll by a factor of 4. </span>
139 <a name="l00187"></a>00187 <span class="comment"> ** Repeat until we've computed numTaps-(4*S->L) coefficients. */</span>
140 <a name="l00188"></a>00188 tapCnt = phaseLen >> 2u;
141 <a name="l00189"></a>00189 <span class="keywordflow">while</span>(tapCnt > 0u)
142 <a name="l00190"></a>00190 {
143 <a name="l00191"></a>00191
144 <a name="l00192"></a>00192 <span class="comment">/* Read the coefficient */</span>
145 <a name="l00193"></a>00193 c0 = *(ptr2);
146 <a name="l00194"></a>00194
147 <a name="l00195"></a>00195 <span class="comment">/* Upsampling is done by stuffing L-1 zeros between each sample. </span>
148 <a name="l00196"></a>00196 <span class="comment"> * So instead of multiplying zeros with coefficients, </span>
149 <a name="l00197"></a>00197 <span class="comment"> * Increment the coefficient pointer by interpolation factor times. */</span>
150 <a name="l00198"></a>00198 ptr2 += S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
151 <a name="l00199"></a>00199
152 <a name="l00200"></a>00200 <span class="comment">/* Read the input sample */</span>
153 <a name="l00201"></a>00201 x0 = *(ptr1++);
154 <a name="l00202"></a>00202
155 <a name="l00203"></a>00203 <span class="comment">/* Perform the multiply-accumulate */</span>
156 <a name="l00204"></a>00204 sum0 += x0 * c0;
157 <a name="l00205"></a>00205
158 <a name="l00206"></a>00206 <span class="comment">/* Read the coefficient */</span>
159 <a name="l00207"></a>00207 c0 = *(ptr2);
160 <a name="l00208"></a>00208
161 <a name="l00209"></a>00209 <span class="comment">/* Increment the coefficient pointer by interpolation factor times. */</span>
162 <a name="l00210"></a>00210 ptr2 += S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
163 <a name="l00211"></a>00211
164 <a name="l00212"></a>00212 <span class="comment">/* Read the input sample */</span>
165 <a name="l00213"></a>00213 x0 = *(ptr1++);
166 <a name="l00214"></a>00214
167 <a name="l00215"></a>00215 <span class="comment">/* Perform the multiply-accumulate */</span>
168 <a name="l00216"></a>00216 sum0 += x0 * c0;
169 <a name="l00217"></a>00217
170 <a name="l00218"></a>00218 <span class="comment">/* Read the coefficient */</span>
171 <a name="l00219"></a>00219 c0 = *(ptr2);
172 <a name="l00220"></a>00220
173 <a name="l00221"></a>00221 <span class="comment">/* Increment the coefficient pointer by interpolation factor times. */</span>
174 <a name="l00222"></a>00222 ptr2 += S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
175 <a name="l00223"></a>00223
176 <a name="l00224"></a>00224 <span class="comment">/* Read the input sample */</span>
177 <a name="l00225"></a>00225 x0 = *(ptr1++);
178 <a name="l00226"></a>00226
179 <a name="l00227"></a>00227 <span class="comment">/* Perform the multiply-accumulate */</span>
180 <a name="l00228"></a>00228 sum0 += x0 * c0;
181 <a name="l00229"></a>00229
182 <a name="l00230"></a>00230 <span class="comment">/* Read the coefficient */</span>
183 <a name="l00231"></a>00231 c0 = *(ptr2);
184 <a name="l00232"></a>00232
185 <a name="l00233"></a>00233 <span class="comment">/* Increment the coefficient pointer by interpolation factor times. */</span>
186 <a name="l00234"></a>00234 ptr2 += S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
187 <a name="l00235"></a>00235
188 <a name="l00236"></a>00236 <span class="comment">/* Read the input sample */</span>
189 <a name="l00237"></a>00237 x0 = *(ptr1++);
190 <a name="l00238"></a>00238
191 <a name="l00239"></a>00239 <span class="comment">/* Perform the multiply-accumulate */</span>
192 <a name="l00240"></a>00240 sum0 += x0 * c0;
193 <a name="l00241"></a>00241
194 <a name="l00242"></a>00242 <span class="comment">/* Decrement the loop counter */</span>
195 <a name="l00243"></a>00243 tapCnt--;
196 <a name="l00244"></a>00244 }
197 <a name="l00245"></a>00245
198 <a name="l00246"></a>00246 <span class="comment">/* If the polyPhase length is not a multiple of 4, compute the remaining filter taps */</span>
199 <a name="l00247"></a>00247 tapCnt = phaseLen % 0x4u;
200 <a name="l00248"></a>00248
201 <a name="l00249"></a>00249 <span class="keywordflow">while</span>(tapCnt > 0u)
202 <a name="l00250"></a>00250 {
203 <a name="l00251"></a>00251 <span class="comment">/* Perform the multiply-accumulate */</span>
204 <a name="l00252"></a>00252 sum0 += *(ptr1++) * (*ptr2);
205 <a name="l00253"></a>00253
206 <a name="l00254"></a>00254 <span class="comment">/* Increment the coefficient pointer by interpolation factor times. */</span>
207 <a name="l00255"></a>00255 ptr2 += S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
208 <a name="l00256"></a>00256
209 <a name="l00257"></a>00257 <span class="comment">/* Decrement the loop counter */</span>
210 <a name="l00258"></a>00258 tapCnt--;
211 <a name="l00259"></a>00259 }
212 <a name="l00260"></a>00260
213 <a name="l00261"></a>00261 <span class="comment">/* The result is in the accumulator, store in the destination buffer. */</span>
214 <a name="l00262"></a>00262 *pDst++ = sum0;
215 <a name="l00263"></a>00263
216 <a name="l00264"></a>00264 <span class="comment">/* Increment the address modifier index of coefficient buffer */</span>
217 <a name="l00265"></a>00265 j++;
218 <a name="l00266"></a>00266
219 <a name="l00267"></a>00267 <span class="comment">/* Decrement the loop counter */</span>
220 <a name="l00268"></a>00268 i--;
221 <a name="l00269"></a>00269 }
222 <a name="l00270"></a>00270
223 <a name="l00271"></a>00271 <span class="comment">/* Advance the state pointer by 1 </span>
224 <a name="l00272"></a>00272 <span class="comment"> * to process the next group of interpolation factor number samples */</span>
225 <a name="l00273"></a>00273 pState = pState + 1;
226 <a name="l00274"></a>00274
227 <a name="l00275"></a>00275 <span class="comment">/* Decrement the loop counter */</span>
228 <a name="l00276"></a>00276 blkCnt--;
229 <a name="l00277"></a>00277 }
230 <a name="l00278"></a>00278
231 <a name="l00279"></a>00279 <span class="comment">/* Processing is complete. </span>
232 <a name="l00280"></a>00280 <span class="comment"> ** Now copy the last phaseLen - 1 samples to the satrt of the state buffer. </span>
233 <a name="l00281"></a>00281 <span class="comment"> ** This prepares the state buffer for the next function call. */</span>
234 <a name="l00282"></a>00282
235 <a name="l00283"></a>00283 <span class="comment">/* Points to the start of the state buffer */</span>
236 <a name="l00284"></a>00284 pStateCurnt = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a42a8ba1bda85fa86d7b6c84d3da4c75b">pState</a>;
237 <a name="l00285"></a>00285
238 <a name="l00286"></a>00286 tapCnt = (phaseLen - 1u) >> 2u;
239 <a name="l00287"></a>00287
240 <a name="l00288"></a>00288 <span class="comment">/* copy data */</span>
241 <a name="l00289"></a>00289 <span class="keywordflow">while</span>(tapCnt > 0u)
242 <a name="l00290"></a>00290 {
243 <a name="l00291"></a>00291 *pStateCurnt++ = *pState++;
244 <a name="l00292"></a>00292 *pStateCurnt++ = *pState++;
245 <a name="l00293"></a>00293 *pStateCurnt++ = *pState++;
246 <a name="l00294"></a>00294 *pStateCurnt++ = *pState++;
247 <a name="l00295"></a>00295
248 <a name="l00296"></a>00296 <span class="comment">/* Decrement the loop counter */</span>
249 <a name="l00297"></a>00297 tapCnt--;
250 <a name="l00298"></a>00298 }
251 <a name="l00299"></a>00299
252 <a name="l00300"></a>00300 tapCnt = (phaseLen - 1u) % 0x04u;
253 <a name="l00301"></a>00301
254 <a name="l00302"></a>00302 <span class="keywordflow">while</span>(tapCnt > 0u)
255 <a name="l00303"></a>00303 {
256 <a name="l00304"></a>00304 *pStateCurnt++ = *pState++;
257 <a name="l00305"></a>00305
258 <a name="l00306"></a>00306 <span class="comment">/* Decrement the loop counter */</span>
259 <a name="l00307"></a>00307 tapCnt--;
260 <a name="l00308"></a>00308 }
261 <a name="l00309"></a>00309
262 <a name="l00310"></a>00310 <span class="preprocessor">#else</span>
263 <a name="l00311"></a>00311 <span class="preprocessor"></span>
264 <a name="l00312"></a>00312 <span class="comment">/* Run the below code for Cortex-M0 */</span>
265 <a name="l00313"></a>00313
266 <a name="l00314"></a>00314 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> sum; <span class="comment">/* Accumulator */</span>
267 <a name="l00315"></a>00315 uint32_t i, blkCnt; <span class="comment">/* Loop counters */</span>
268 <a name="l00316"></a>00316 uint16_t phaseLen = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a389e669e13ec56292a70db8e92194b12">phaseLength</a>, tapCnt; <span class="comment">/* Length of each polyphase filter component */</span>
269 <a name="l00317"></a>00317
270 <a name="l00318"></a>00318
271 <a name="l00319"></a>00319 <span class="comment">/* S->pState buffer contains previous frame (phaseLen - 1) samples */</span>
272 <a name="l00320"></a>00320 <span class="comment">/* pStateCurnt points to the location where the new input data should be written */</span>
273 <a name="l00321"></a>00321 pStateCurnt = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a42a8ba1bda85fa86d7b6c84d3da4c75b">pState</a> + (phaseLen - 1u);
274 <a name="l00322"></a>00322
275 <a name="l00323"></a>00323 <span class="comment">/* Total number of intput samples */</span>
276 <a name="l00324"></a>00324 blkCnt = <a class="code" href="arm__fir__example__f32_8c.html#ab6558f40a619c2502fbc24c880fd4fb0">blockSize</a>;
277 <a name="l00325"></a>00325
278 <a name="l00326"></a>00326 <span class="comment">/* Loop over the blockSize. */</span>
279 <a name="l00327"></a>00327 <span class="keywordflow">while</span>(blkCnt > 0u)
280 <a name="l00328"></a>00328 {
281 <a name="l00329"></a>00329 <span class="comment">/* Copy new input sample into the state buffer */</span>
282 <a name="l00330"></a>00330 *pStateCurnt++ = *pSrc++;
283 <a name="l00331"></a>00331
284 <a name="l00332"></a>00332 <span class="comment">/* Loop over the Interpolation factor. */</span>
285 <a name="l00333"></a>00333 i = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
286 <a name="l00334"></a>00334
287 <a name="l00335"></a>00335 <span class="keywordflow">while</span>(i > 0u)
288 <a name="l00336"></a>00336 {
289 <a name="l00337"></a>00337 <span class="comment">/* Set accumulator to zero */</span>
290 <a name="l00338"></a>00338 sum = 0.0f;
291 <a name="l00339"></a>00339
292 <a name="l00340"></a>00340 <span class="comment">/* Initialize state pointer */</span>
293 <a name="l00341"></a>00341 ptr1 = pState;
294 <a name="l00342"></a>00342
295 <a name="l00343"></a>00343 <span class="comment">/* Initialize coefficient pointer */</span>
296 <a name="l00344"></a>00344 ptr2 = pCoeffs + (i - 1u);
297 <a name="l00345"></a>00345
298 <a name="l00346"></a>00346 <span class="comment">/* Loop over the polyPhase length */</span>
299 <a name="l00347"></a>00347 tapCnt = phaseLen;
300 <a name="l00348"></a>00348
301 <a name="l00349"></a>00349 <span class="keywordflow">while</span>(tapCnt > 0u)
302 <a name="l00350"></a>00350 {
303 <a name="l00351"></a>00351 <span class="comment">/* Perform the multiply-accumulate */</span>
304 <a name="l00352"></a>00352 sum += *ptr1++ * *ptr2;
305 <a name="l00353"></a>00353
306 <a name="l00354"></a>00354 <span class="comment">/* Increment the coefficient pointer by interpolation factor times. */</span>
307 <a name="l00355"></a>00355 ptr2 += S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#ae6f94dcc0ccd8aa4bc699b20985d9df5">L</a>;
308 <a name="l00356"></a>00356
309 <a name="l00357"></a>00357 <span class="comment">/* Decrement the loop counter */</span>
310 <a name="l00358"></a>00358 tapCnt--;
311 <a name="l00359"></a>00359 }
312 <a name="l00360"></a>00360
313 <a name="l00361"></a>00361 <span class="comment">/* The result is in the accumulator, store in the destination buffer. */</span>
314 <a name="l00362"></a>00362 *pDst++ = sum;
315 <a name="l00363"></a>00363
316 <a name="l00364"></a>00364 <span class="comment">/* Decrement the loop counter */</span>
317 <a name="l00365"></a>00365 i--;
318 <a name="l00366"></a>00366 }
319 <a name="l00367"></a>00367
320 <a name="l00368"></a>00368 <span class="comment">/* Advance the state pointer by 1 </span>
321 <a name="l00369"></a>00369 <span class="comment"> * to process the next group of interpolation factor number samples */</span>
322 <a name="l00370"></a>00370 pState = pState + 1;
323 <a name="l00371"></a>00371
324 <a name="l00372"></a>00372 <span class="comment">/* Decrement the loop counter */</span>
325 <a name="l00373"></a>00373 blkCnt--;
326 <a name="l00374"></a>00374 }
327 <a name="l00375"></a>00375
328 <a name="l00376"></a>00376 <span class="comment">/* Processing is complete. </span>
329 <a name="l00377"></a>00377 <span class="comment"> ** Now copy the last phaseLen - 1 samples to the start of the state buffer. </span>
330 <a name="l00378"></a>00378 <span class="comment"> ** This prepares the state buffer for the next function call. */</span>
331 <a name="l00379"></a>00379
332 <a name="l00380"></a>00380 <span class="comment">/* Points to the start of the state buffer */</span>
333 <a name="l00381"></a>00381 pStateCurnt = S-><a class="code" href="structarm__fir__interpolate__instance__f32.html#a42a8ba1bda85fa86d7b6c84d3da4c75b">pState</a>;
334 <a name="l00382"></a>00382
335 <a name="l00383"></a>00383 tapCnt = phaseLen - 1u;
336 <a name="l00384"></a>00384
337 <a name="l00385"></a>00385 <span class="keywordflow">while</span>(tapCnt > 0u)
338 <a name="l00386"></a>00386 {
339 <a name="l00387"></a>00387 *pStateCurnt++ = *pState++;
340 <a name="l00388"></a>00388
341 <a name="l00389"></a>00389 <span class="comment">/* Decrement the loop counter */</span>
342 <a name="l00390"></a>00390 tapCnt--;
343 <a name="l00391"></a>00391 }
344 <a name="l00392"></a>00392
345 <a name="l00393"></a>00393 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_CM0 */</span>
346 <a name="l00394"></a>00394
347 <a name="l00395"></a>00395 }
348 <a name="l00396"></a>00396
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