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| <h1>arm_biquad_cascade_df1_f32.c</h1> </div> |
| </div> |
| <div class="contents"> |
| <a href="arm__biquad__cascade__df1__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> |
| <a name="l00002"></a>00002 <span class="comment">* Copyright (C) 2010 ARM Limited. All rights reserved. </span> |
| <a name="l00003"></a>00003 <span class="comment">* </span> |
| <a name="l00004"></a>00004 <span class="comment">* $Date: 15. July 2011 </span> |
| <a name="l00005"></a>00005 <span class="comment">* $Revision: V1.0.10 </span> |
| <a name="l00006"></a>00006 <span class="comment">* </span> |
| <a name="l00007"></a>00007 <span class="comment">* Project: CMSIS DSP Library </span> |
| <a name="l00008"></a>00008 <span class="comment">* Title: arm_biquad_cascade_df1_f32.c </span> |
| <a name="l00009"></a>00009 <span class="comment">* </span> |
| <a name="l00010"></a>00010 <span class="comment">* Description: Processing function for the </span> |
| <a name="l00011"></a>00011 <span class="comment">* floating-point Biquad cascade DirectFormI(DF1) filter. </span> |
| <a name="l00012"></a>00012 <span class="comment">* </span> |
| <a name="l00013"></a>00013 <span class="comment">* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0</span> |
| <a name="l00014"></a>00014 <span class="comment">* </span> |
| <a name="l00015"></a>00015 <span class="comment">* Version 1.0.10 2011/7/15 </span> |
| <a name="l00016"></a>00016 <span class="comment">* Big Endian support added and Merged M0 and M3/M4 Source code. </span> |
| <a name="l00017"></a>00017 <span class="comment">* </span> |
| <a name="l00018"></a>00018 <span class="comment">* Version 1.0.3 2010/11/29 </span> |
| <a name="l00019"></a>00019 <span class="comment">* Re-organized the CMSIS folders and updated documentation. </span> |
| <a name="l00020"></a>00020 <span class="comment">* </span> |
| <a name="l00021"></a>00021 <span class="comment">* Version 1.0.2 2010/11/11 </span> |
| <a name="l00022"></a>00022 <span class="comment">* Documentation updated. </span> |
| <a name="l00023"></a>00023 <span class="comment">* </span> |
| <a name="l00024"></a>00024 <span class="comment">* Version 1.0.1 2010/10/05 </span> |
| <a name="l00025"></a>00025 <span class="comment">* Production release and review comments incorporated. </span> |
| <a name="l00026"></a>00026 <span class="comment">* </span> |
| <a name="l00027"></a>00027 <span class="comment">* Version 1.0.0 2010/09/20 </span> |
| <a name="l00028"></a>00028 <span class="comment">* Production release and review comments incorporated. </span> |
| <a name="l00029"></a>00029 <span class="comment">* </span> |
| <a name="l00030"></a>00030 <span class="comment">* Version 0.0.5 2010/04/26 </span> |
| <a name="l00031"></a>00031 <span class="comment">* incorporated review comments and updated with latest CMSIS layer </span> |
| <a name="l00032"></a>00032 <span class="comment">* </span> |
| <a name="l00033"></a>00033 <span class="comment">* Version 0.0.3 2010/03/10 </span> |
| <a name="l00034"></a>00034 <span class="comment">* Initial version </span> |
| <a name="l00035"></a>00035 <span class="comment">* -------------------------------------------------------------------- */</span> |
| <a name="l00036"></a>00036 |
| <a name="l00037"></a>00037 <span class="preprocessor">#include "<a class="code" href="arm__math_8h.html">arm_math.h</a>"</span> |
| <a name="l00038"></a>00038 |
| <a name="l00171"></a><a class="code" href="group___biquad_cascade_d_f1.html#gaa0dbe330d763e3c1d8030b3ef12d5bdc">00171</a> <span class="keywordtype">void</span> <a class="code" href="group___biquad_cascade_d_f1.html#gaa0dbe330d763e3c1d8030b3ef12d5bdc" title="Processing function for the floating-point Biquad cascade filter.">arm_biquad_cascade_df1_f32</a>( |
| <a name="l00172"></a>00172 <span class="keyword">const</span> <a class="code" href="structarm__biquad__casd__df1__inst__f32.html" title="Instance structure for the floating-point Biquad cascade filter.">arm_biquad_casd_df1_inst_f32</a> * S, |
| <a name="l00173"></a>00173 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> * pSrc, |
| <a name="l00174"></a>00174 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> * pDst, |
| <a name="l00175"></a>00175 uint32_t <a class="code" href="arm__fir__example__f32_8c.html#ab6558f40a619c2502fbc24c880fd4fb0">blockSize</a>) |
| <a name="l00176"></a>00176 { |
| <a name="l00177"></a>00177 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> *pIn = pSrc; <span class="comment">/* source pointer */</span> |
| <a name="l00178"></a>00178 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> *pOut = pDst; <span class="comment">/* destination pointer */</span> |
| <a name="l00179"></a>00179 <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__biquad__casd__df1__inst__f32.html#a8c245d79e0d8cfabc82409d4b54fb682">pState</a>; <span class="comment">/* pState pointer */</span> |
| <a name="l00180"></a>00180 <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__biquad__casd__df1__inst__f32.html#af9df3820576fb921809d1462c9c6d16c">pCoeffs</a>; <span class="comment">/* coefficient pointer */</span> |
| <a name="l00181"></a>00181 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> acc; <span class="comment">/* Simulates the accumulator */</span> |
| <a name="l00182"></a>00182 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> b0, b1, b2, a1, a2; <span class="comment">/* Filter coefficients */</span> |
| <a name="l00183"></a>00183 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> Xn1, Xn2, Yn1, Yn2; <span class="comment">/* Filter pState variables */</span> |
| <a name="l00184"></a>00184 <a class="code" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715" title="32-bit floating-point type definition.">float32_t</a> Xn; <span class="comment">/* temporary input */</span> |
| <a name="l00185"></a>00185 uint32_t sample, stage = S-><a class="code" href="structarm__biquad__casd__df1__inst__f32.html#af69820c37a87252c46453e4cfe120585">numStages</a>; <span class="comment">/* loop counters */</span> |
| <a name="l00186"></a>00186 |
| <a name="l00187"></a>00187 |
| <a name="l00188"></a>00188 <span class="preprocessor">#ifndef ARM_MATH_CM0</span> |
| <a name="l00189"></a>00189 <span class="preprocessor"></span> |
| <a name="l00190"></a>00190 <span class="comment">/* Run the below code for Cortex-M4 and Cortex-M3 */</span> |
| <a name="l00191"></a>00191 |
| <a name="l00192"></a>00192 <span class="keywordflow">do</span> |
| <a name="l00193"></a>00193 { |
| <a name="l00194"></a>00194 <span class="comment">/* Reading the coefficients */</span> |
| <a name="l00195"></a>00195 b0 = *pCoeffs++; |
| <a name="l00196"></a>00196 b1 = *pCoeffs++; |
| <a name="l00197"></a>00197 b2 = *pCoeffs++; |
| <a name="l00198"></a>00198 a1 = *pCoeffs++; |
| <a name="l00199"></a>00199 a2 = *pCoeffs++; |
| <a name="l00200"></a>00200 |
| <a name="l00201"></a>00201 <span class="comment">/* Reading the pState values */</span> |
| <a name="l00202"></a>00202 Xn1 = pState[0]; |
| <a name="l00203"></a>00203 Xn2 = pState[1]; |
| <a name="l00204"></a>00204 Yn1 = pState[2]; |
| <a name="l00205"></a>00205 Yn2 = pState[3]; |
| <a name="l00206"></a>00206 |
| <a name="l00207"></a>00207 <span class="comment">/* Apply loop unrolling and compute 4 output values simultaneously. */</span> |
| <a name="l00208"></a>00208 <span class="comment">/* The variable acc hold output values that are being computed: </span> |
| <a name="l00209"></a>00209 <span class="comment"> * </span> |
| <a name="l00210"></a>00210 <span class="comment"> * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] </span> |
| <a name="l00211"></a>00211 <span class="comment"> * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] </span> |
| <a name="l00212"></a>00212 <span class="comment"> * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] </span> |
| <a name="l00213"></a>00213 <span class="comment"> * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] </span> |
| <a name="l00214"></a>00214 <span class="comment"> */</span> |
| <a name="l00215"></a>00215 |
| <a name="l00216"></a>00216 sample = blockSize >> 2u; |
| <a name="l00217"></a>00217 |
| <a name="l00218"></a>00218 <span class="comment">/* First part of the processing with loop unrolling. Compute 4 outputs at a time. </span> |
| <a name="l00219"></a>00219 <span class="comment"> ** a second loop below computes the remaining 1 to 3 samples. */</span> |
| <a name="l00220"></a>00220 <span class="keywordflow">while</span>(sample > 0u) |
| <a name="l00221"></a>00221 { |
| <a name="l00222"></a>00222 <span class="comment">/* Read the first input */</span> |
| <a name="l00223"></a>00223 Xn = *pIn++; |
| <a name="l00224"></a>00224 |
| <a name="l00225"></a>00225 <span class="comment">/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */</span> |
| <a name="l00226"></a>00226 Yn2 = (b0 * Xn) + (b1 * Xn1) + (b2 * Xn2) + (a1 * Yn1) + (a2 * Yn2); |
| <a name="l00227"></a>00227 |
| <a name="l00228"></a>00228 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00229"></a>00229 *pOut++ = Yn2; |
| <a name="l00230"></a>00230 |
| <a name="l00231"></a>00231 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00232"></a>00232 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00233"></a>00233 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00234"></a>00234 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00235"></a>00235 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00236"></a>00236 <span class="comment">/* Yn1 = acc */</span> |
| <a name="l00237"></a>00237 |
| <a name="l00238"></a>00238 <span class="comment">/* Read the second input */</span> |
| <a name="l00239"></a>00239 Xn2 = *pIn++; |
| <a name="l00240"></a>00240 |
| <a name="l00241"></a>00241 <span class="comment">/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */</span> |
| <a name="l00242"></a>00242 Yn1 = (b0 * Xn2) + (b1 * Xn) + (b2 * Xn1) + (a1 * Yn2) + (a2 * Yn1); |
| <a name="l00243"></a>00243 |
| <a name="l00244"></a>00244 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00245"></a>00245 *pOut++ = Yn1; |
| <a name="l00246"></a>00246 |
| <a name="l00247"></a>00247 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00248"></a>00248 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00249"></a>00249 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00250"></a>00250 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00251"></a>00251 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00252"></a>00252 <span class="comment">/* Yn1 = acc */</span> |
| <a name="l00253"></a>00253 |
| <a name="l00254"></a>00254 <span class="comment">/* Read the third input */</span> |
| <a name="l00255"></a>00255 Xn1 = *pIn++; |
| <a name="l00256"></a>00256 |
| <a name="l00257"></a>00257 <span class="comment">/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */</span> |
| <a name="l00258"></a>00258 Yn2 = (b0 * Xn1) + (b1 * Xn2) + (b2 * Xn) + (a1 * Yn1) + (a2 * Yn2); |
| <a name="l00259"></a>00259 |
| <a name="l00260"></a>00260 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00261"></a>00261 *pOut++ = Yn2; |
| <a name="l00262"></a>00262 |
| <a name="l00263"></a>00263 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00264"></a>00264 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00265"></a>00265 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00266"></a>00266 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00267"></a>00267 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00268"></a>00268 <span class="comment">/* Yn1 = acc */</span> |
| <a name="l00269"></a>00269 |
| <a name="l00270"></a>00270 <span class="comment">/* Read the forth input */</span> |
| <a name="l00271"></a>00271 Xn = *pIn++; |
| <a name="l00272"></a>00272 |
| <a name="l00273"></a>00273 <span class="comment">/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */</span> |
| <a name="l00274"></a>00274 Yn1 = (b0 * Xn) + (b1 * Xn1) + (b2 * Xn2) + (a1 * Yn2) + (a2 * Yn1); |
| <a name="l00275"></a>00275 |
| <a name="l00276"></a>00276 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00277"></a>00277 *pOut++ = Yn1; |
| <a name="l00278"></a>00278 |
| <a name="l00279"></a>00279 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00280"></a>00280 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00281"></a>00281 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00282"></a>00282 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00283"></a>00283 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00284"></a>00284 <span class="comment">/* Yn1 = acc */</span> |
| <a name="l00285"></a>00285 Xn2 = Xn1; |
| <a name="l00286"></a>00286 Xn1 = Xn; |
| <a name="l00287"></a>00287 |
| <a name="l00288"></a>00288 <span class="comment">/* decrement the loop counter */</span> |
| <a name="l00289"></a>00289 sample--; |
| <a name="l00290"></a>00290 |
| <a name="l00291"></a>00291 } |
| <a name="l00292"></a>00292 |
| <a name="l00293"></a>00293 <span class="comment">/* If the blockSize is not a multiple of 4, compute any remaining output samples here. </span> |
| <a name="l00294"></a>00294 <span class="comment"> ** No loop unrolling is used. */</span> |
| <a name="l00295"></a>00295 sample = blockSize & 0x3u; |
| <a name="l00296"></a>00296 |
| <a name="l00297"></a>00297 <span class="keywordflow">while</span>(sample > 0u) |
| <a name="l00298"></a>00298 { |
| <a name="l00299"></a>00299 <span class="comment">/* Read the input */</span> |
| <a name="l00300"></a>00300 Xn = *pIn++; |
| <a name="l00301"></a>00301 |
| <a name="l00302"></a>00302 <span class="comment">/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */</span> |
| <a name="l00303"></a>00303 acc = (b0 * Xn) + (b1 * Xn1) + (b2 * Xn2) + (a1 * Yn1) + (a2 * Yn2); |
| <a name="l00304"></a>00304 |
| <a name="l00305"></a>00305 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00306"></a>00306 *pOut++ = acc; |
| <a name="l00307"></a>00307 |
| <a name="l00308"></a>00308 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00309"></a>00309 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00310"></a>00310 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00311"></a>00311 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00312"></a>00312 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00313"></a>00313 <span class="comment">/* Yn1 = acc */</span> |
| <a name="l00314"></a>00314 Xn2 = Xn1; |
| <a name="l00315"></a>00315 Xn1 = Xn; |
| <a name="l00316"></a>00316 Yn2 = Yn1; |
| <a name="l00317"></a>00317 Yn1 = acc; |
| <a name="l00318"></a>00318 |
| <a name="l00319"></a>00319 <span class="comment">/* decrement the loop counter */</span> |
| <a name="l00320"></a>00320 sample--; |
| <a name="l00321"></a>00321 |
| <a name="l00322"></a>00322 } |
| <a name="l00323"></a>00323 |
| <a name="l00324"></a>00324 <span class="comment">/* Store the updated state variables back into the pState array */</span> |
| <a name="l00325"></a>00325 *pState++ = Xn1; |
| <a name="l00326"></a>00326 *pState++ = Xn2; |
| <a name="l00327"></a>00327 *pState++ = Yn1; |
| <a name="l00328"></a>00328 *pState++ = Yn2; |
| <a name="l00329"></a>00329 |
| <a name="l00330"></a>00330 <span class="comment">/* The first stage goes from the input buffer to the output buffer. */</span> |
| <a name="l00331"></a>00331 <span class="comment">/* Subsequent numStages occur in-place in the output buffer */</span> |
| <a name="l00332"></a>00332 pIn = pDst; |
| <a name="l00333"></a>00333 |
| <a name="l00334"></a>00334 <span class="comment">/* Reset the output pointer */</span> |
| <a name="l00335"></a>00335 pOut = pDst; |
| <a name="l00336"></a>00336 |
| <a name="l00337"></a>00337 <span class="comment">/* decrement the loop counter */</span> |
| <a name="l00338"></a>00338 stage--; |
| <a name="l00339"></a>00339 |
| <a name="l00340"></a>00340 } <span class="keywordflow">while</span>(stage > 0u); |
| <a name="l00341"></a>00341 |
| <a name="l00342"></a>00342 <span class="preprocessor">#else</span> |
| <a name="l00343"></a>00343 <span class="preprocessor"></span> |
| <a name="l00344"></a>00344 <span class="comment">/* Run the below code for Cortex-M0 */</span> |
| <a name="l00345"></a>00345 |
| <a name="l00346"></a>00346 <span class="keywordflow">do</span> |
| <a name="l00347"></a>00347 { |
| <a name="l00348"></a>00348 <span class="comment">/* Reading the coefficients */</span> |
| <a name="l00349"></a>00349 b0 = *pCoeffs++; |
| <a name="l00350"></a>00350 b1 = *pCoeffs++; |
| <a name="l00351"></a>00351 b2 = *pCoeffs++; |
| <a name="l00352"></a>00352 a1 = *pCoeffs++; |
| <a name="l00353"></a>00353 a2 = *pCoeffs++; |
| <a name="l00354"></a>00354 |
| <a name="l00355"></a>00355 <span class="comment">/* Reading the pState values */</span> |
| <a name="l00356"></a>00356 Xn1 = pState[0]; |
| <a name="l00357"></a>00357 Xn2 = pState[1]; |
| <a name="l00358"></a>00358 Yn1 = pState[2]; |
| <a name="l00359"></a>00359 Yn2 = pState[3]; |
| <a name="l00360"></a>00360 |
| <a name="l00361"></a>00361 <span class="comment">/* The variables acc holds the output value that is computed: </span> |
| <a name="l00362"></a>00362 <span class="comment"> * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] </span> |
| <a name="l00363"></a>00363 <span class="comment"> */</span> |
| <a name="l00364"></a>00364 |
| <a name="l00365"></a>00365 sample = <a class="code" href="arm__fir__example__f32_8c.html#ab6558f40a619c2502fbc24c880fd4fb0">blockSize</a>; |
| <a name="l00366"></a>00366 |
| <a name="l00367"></a>00367 <span class="keywordflow">while</span>(sample > 0u) |
| <a name="l00368"></a>00368 { |
| <a name="l00369"></a>00369 <span class="comment">/* Read the input */</span> |
| <a name="l00370"></a>00370 Xn = *pIn++; |
| <a name="l00371"></a>00371 |
| <a name="l00372"></a>00372 <span class="comment">/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */</span> |
| <a name="l00373"></a>00373 acc = (b0 * Xn) + (b1 * Xn1) + (b2 * Xn2) + (a1 * Yn1) + (a2 * Yn2); |
| <a name="l00374"></a>00374 |
| <a name="l00375"></a>00375 <span class="comment">/* Store the result in the accumulator in the destination buffer. */</span> |
| <a name="l00376"></a>00376 *pOut++ = acc; |
| <a name="l00377"></a>00377 |
| <a name="l00378"></a>00378 <span class="comment">/* Every time after the output is computed state should be updated. */</span> |
| <a name="l00379"></a>00379 <span class="comment">/* The states should be updated as: */</span> |
| <a name="l00380"></a>00380 <span class="comment">/* Xn2 = Xn1 */</span> |
| <a name="l00381"></a>00381 <span class="comment">/* Xn1 = Xn */</span> |
| <a name="l00382"></a>00382 <span class="comment">/* Yn2 = Yn1 */</span> |
| <a name="l00383"></a>00383 <span class="comment">/* Yn1 = acc */</span> |
| <a name="l00384"></a>00384 Xn2 = Xn1; |
| <a name="l00385"></a>00385 Xn1 = Xn; |
| <a name="l00386"></a>00386 Yn2 = Yn1; |
| <a name="l00387"></a>00387 Yn1 = acc; |
| <a name="l00388"></a>00388 |
| <a name="l00389"></a>00389 <span class="comment">/* decrement the loop counter */</span> |
| <a name="l00390"></a>00390 sample--; |
| <a name="l00391"></a>00391 } |
| <a name="l00392"></a>00392 |
| <a name="l00393"></a>00393 <span class="comment">/* Store the updated state variables back into the pState array */</span> |
| <a name="l00394"></a>00394 *pState++ = Xn1; |
| <a name="l00395"></a>00395 *pState++ = Xn2; |
| <a name="l00396"></a>00396 *pState++ = Yn1; |
| <a name="l00397"></a>00397 *pState++ = Yn2; |
| <a name="l00398"></a>00398 |
| <a name="l00399"></a>00399 <span class="comment">/* The first stage goes from the input buffer to the output buffer. */</span> |
| <a name="l00400"></a>00400 <span class="comment">/* Subsequent numStages occur in-place in the output buffer */</span> |
| <a name="l00401"></a>00401 pIn = pDst; |
| <a name="l00402"></a>00402 |
| <a name="l00403"></a>00403 <span class="comment">/* Reset the output pointer */</span> |
| <a name="l00404"></a>00404 pOut = pDst; |
| <a name="l00405"></a>00405 |
| <a name="l00406"></a>00406 <span class="comment">/* decrement the loop counter */</span> |
| <a name="l00407"></a>00407 stage--; |
| <a name="l00408"></a>00408 |
| <a name="l00409"></a>00409 } <span class="keywordflow">while</span>(stage > 0u); |
| <a name="l00410"></a>00410 |
| <a name="l00411"></a>00411 <span class="preprocessor">#endif </span><span class="comment">/* #ifndef ARM_MATH_CM0 */</span> |
| <a name="l00412"></a>00412 |
| <a name="l00413"></a>00413 } |
| <a name="l00414"></a>00414 |
| <a name="l00415"></a>00415 |
| </pre></div></div> |
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