Eli Hughes / CMSIS_DSP_401

V4.0.1 of the ARM CMSIS DSP libraries. Note that arm_bitreversal2.s, arm_cfft_f32.c and arm_rfft_fast_f32.c had to be removed. arm_bitreversal2.s will not assemble with the online tools. So, the fast f32 FFT functions are not yet available. All the other FFT functions are available.

Dependents:   MPU9150_Example fir_f32 fir_f32 MPU9150_nucleo_noni2cdev ... more

FilteringFunctions/arm_lms_q31.c@0:3d9c67d97d6f, 2014-07-28 (annotated)

Committer:
emh203
Date:
Mon Jul 28 15:03:15 2014 +0000
Revision:
0:3d9c67d97d6f
1st working commit.   Had to remove arm_bitreversal2.s     arm_cfft_f32.c and arm_rfft_fast_f32.c.    The .s will not assemble.      For now I removed these functions so we could at least have a library for the other functions.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emh203 0:3d9c67d97d6f 1 /* ----------------------------------------------------------------------
emh203 0:3d9c67d97d6f 2 * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
emh203 0:3d9c67d97d6f 3 *
emh203 0:3d9c67d97d6f 4 * $Date: 12. March 2014
emh203 0:3d9c67d97d6f 5 * $Revision: V1.4.3
emh203 0:3d9c67d97d6f 6 *
emh203 0:3d9c67d97d6f 7 * Project: CMSIS DSP Library
emh203 0:3d9c67d97d6f 8 * Title: arm_lms_q31.c
emh203 0:3d9c67d97d6f 9 *
emh203 0:3d9c67d97d6f 10 * Description: Processing function for the Q31 LMS filter.
emh203 0:3d9c67d97d6f 11 *
emh203 0:3d9c67d97d6f 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
emh203 0:3d9c67d97d6f 13 *
emh203 0:3d9c67d97d6f 14 * Redistribution and use in source and binary forms, with or without
emh203 0:3d9c67d97d6f 15 * modification, are permitted provided that the following conditions
emh203 0:3d9c67d97d6f 16 * are met:
emh203 0:3d9c67d97d6f 17 * - Redistributions of source code must retain the above copyright
emh203 0:3d9c67d97d6f 18 * notice, this list of conditions and the following disclaimer.
emh203 0:3d9c67d97d6f 19 * - Redistributions in binary form must reproduce the above copyright
emh203 0:3d9c67d97d6f 20 * notice, this list of conditions and the following disclaimer in
emh203 0:3d9c67d97d6f 21 * the documentation and/or other materials provided with the
emh203 0:3d9c67d97d6f 22 * distribution.
emh203 0:3d9c67d97d6f 23 * - Neither the name of ARM LIMITED nor the names of its contributors
emh203 0:3d9c67d97d6f 24 * may be used to endorse or promote products derived from this
emh203 0:3d9c67d97d6f 25 * software without specific prior written permission.
emh203 0:3d9c67d97d6f 26 *
emh203 0:3d9c67d97d6f 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
emh203 0:3d9c67d97d6f 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
emh203 0:3d9c67d97d6f 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
emh203 0:3d9c67d97d6f 30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
emh203 0:3d9c67d97d6f 31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
emh203 0:3d9c67d97d6f 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
emh203 0:3d9c67d97d6f 33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
emh203 0:3d9c67d97d6f 34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
emh203 0:3d9c67d97d6f 35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
emh203 0:3d9c67d97d6f 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
emh203 0:3d9c67d97d6f 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
emh203 0:3d9c67d97d6f 38 * POSSIBILITY OF SUCH DAMAGE.
emh203 0:3d9c67d97d6f 39 * -------------------------------------------------------------------- */
emh203 0:3d9c67d97d6f 40
emh203 0:3d9c67d97d6f 41 #include "arm_math.h"
emh203 0:3d9c67d97d6f 42 /**
emh203 0:3d9c67d97d6f 43 * @ingroup groupFilters
emh203 0:3d9c67d97d6f 44 */
emh203 0:3d9c67d97d6f 45
emh203 0:3d9c67d97d6f 46 /**
emh203 0:3d9c67d97d6f 47 * @addtogroup LMS
emh203 0:3d9c67d97d6f 48 * @{
emh203 0:3d9c67d97d6f 49 */
emh203 0:3d9c67d97d6f 50
emh203 0:3d9c67d97d6f 51 /**
emh203 0:3d9c67d97d6f 52 * @brief Processing function for Q31 LMS filter.
emh203 0:3d9c67d97d6f 53 * @param[in] *S points to an instance of the Q15 LMS filter structure.
emh203 0:3d9c67d97d6f 54 * @param[in] *pSrc points to the block of input data.
emh203 0:3d9c67d97d6f 55 * @param[in] *pRef points to the block of reference data.
emh203 0:3d9c67d97d6f 56 * @param[out] *pOut points to the block of output data.
emh203 0:3d9c67d97d6f 57 * @param[out] *pErr points to the block of error data.
emh203 0:3d9c67d97d6f 58 * @param[in] blockSize number of samples to process.
emh203 0:3d9c67d97d6f 59 * @return none.
emh203 0:3d9c67d97d6f 60 *
emh203 0:3d9c67d97d6f 61 * \par Scaling and Overflow Behavior:
emh203 0:3d9c67d97d6f 62 * The function is implemented using an internal 64-bit accumulator.
emh203 0:3d9c67d97d6f 63 * The accumulator has a 2.62 format and maintains full precision of the intermediate
emh203 0:3d9c67d97d6f 64 * multiplication results but provides only a single guard bit.
emh203 0:3d9c67d97d6f 65 * Thus, if the accumulator result overflows it wraps around rather than clips.
emh203 0:3d9c67d97d6f 66 * In order to avoid overflows completely the input signal must be scaled down by
emh203 0:3d9c67d97d6f 67 * log2(numTaps) bits.
emh203 0:3d9c67d97d6f 68 * The reference signal should not be scaled down.
emh203 0:3d9c67d97d6f 69 * After all multiply-accumulates are performed, the 2.62 accumulator is shifted
emh203 0:3d9c67d97d6f 70 * and saturated to 1.31 format to yield the final result.
emh203 0:3d9c67d97d6f 71 * The output signal and error signal are in 1.31 format.
emh203 0:3d9c67d97d6f 72 *
emh203 0:3d9c67d97d6f 73 * \par
emh203 0:3d9c67d97d6f 74 * In this filter, filter coefficients are updated for each sample and the updation of filter cofficients are saturted.
emh203 0:3d9c67d97d6f 75 */
emh203 0:3d9c67d97d6f 76
emh203 0:3d9c67d97d6f 77 void arm_lms_q31(
emh203 0:3d9c67d97d6f 78 const arm_lms_instance_q31 * S,
emh203 0:3d9c67d97d6f 79 q31_t * pSrc,
emh203 0:3d9c67d97d6f 80 q31_t * pRef,
emh203 0:3d9c67d97d6f 81 q31_t * pOut,
emh203 0:3d9c67d97d6f 82 q31_t * pErr,
emh203 0:3d9c67d97d6f 83 uint32_t blockSize)
emh203 0:3d9c67d97d6f 84 {
emh203 0:3d9c67d97d6f 85 q31_t *pState = S->pState; /* State pointer */
emh203 0:3d9c67d97d6f 86 uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
emh203 0:3d9c67d97d6f 87 q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
emh203 0:3d9c67d97d6f 88 q31_t *pStateCurnt; /* Points to the current sample of the state */
emh203 0:3d9c67d97d6f 89 q31_t mu = S->mu; /* Adaptive factor */
emh203 0:3d9c67d97d6f 90 q31_t *px; /* Temporary pointer for state */
emh203 0:3d9c67d97d6f 91 q31_t *pb; /* Temporary pointer for coefficient buffer */
emh203 0:3d9c67d97d6f 92 uint32_t tapCnt, blkCnt; /* Loop counters */
emh203 0:3d9c67d97d6f 93 q63_t acc; /* Accumulator */
emh203 0:3d9c67d97d6f 94 q31_t e = 0; /* error of data sample */
emh203 0:3d9c67d97d6f 95 q31_t alpha; /* Intermediate constant for taps update */
emh203 0:3d9c67d97d6f 96 q31_t coef; /* Temporary variable for coef */
emh203 0:3d9c67d97d6f 97 q31_t acc_l, acc_h; /* temporary input */
emh203 0:3d9c67d97d6f 98 uint32_t uShift = ((uint32_t) S->postShift + 1u);
emh203 0:3d9c67d97d6f 99 uint32_t lShift = 32u - uShift; /* Shift to be applied to the output */
emh203 0:3d9c67d97d6f 100
emh203 0:3d9c67d97d6f 101 /* S->pState points to buffer which contains previous frame (numTaps - 1) samples */
emh203 0:3d9c67d97d6f 102 /* pStateCurnt points to the location where the new input data should be written */
emh203 0:3d9c67d97d6f 103 pStateCurnt = &(S->pState[(numTaps - 1u)]);
emh203 0:3d9c67d97d6f 104
emh203 0:3d9c67d97d6f 105 /* Initializing blkCnt with blockSize */
emh203 0:3d9c67d97d6f 106 blkCnt = blockSize;
emh203 0:3d9c67d97d6f 107
emh203 0:3d9c67d97d6f 108
emh203 0:3d9c67d97d6f 109 #ifndef ARM_MATH_CM0_FAMILY
emh203 0:3d9c67d97d6f 110
emh203 0:3d9c67d97d6f 111 /* Run the below code for Cortex-M4 and Cortex-M3 */
emh203 0:3d9c67d97d6f 112
emh203 0:3d9c67d97d6f 113 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 114 {
emh203 0:3d9c67d97d6f 115 /* Copy the new input sample into the state buffer */
emh203 0:3d9c67d97d6f 116 *pStateCurnt++ = *pSrc++;
emh203 0:3d9c67d97d6f 117
emh203 0:3d9c67d97d6f 118 /* Initialize state pointer */
emh203 0:3d9c67d97d6f 119 px = pState;
emh203 0:3d9c67d97d6f 120
emh203 0:3d9c67d97d6f 121 /* Initialize coefficient pointer */
emh203 0:3d9c67d97d6f 122 pb = pCoeffs;
emh203 0:3d9c67d97d6f 123
emh203 0:3d9c67d97d6f 124 /* Set the accumulator to zero */
emh203 0:3d9c67d97d6f 125 acc = 0;
emh203 0:3d9c67d97d6f 126
emh203 0:3d9c67d97d6f 127 /* Loop unrolling. Process 4 taps at a time. */
emh203 0:3d9c67d97d6f 128 tapCnt = numTaps >> 2;
emh203 0:3d9c67d97d6f 129
emh203 0:3d9c67d97d6f 130 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 131 {
emh203 0:3d9c67d97d6f 132 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 133 /* acc += b[N] * x[n-N] */
emh203 0:3d9c67d97d6f 134 acc += ((q63_t) (*px++)) * (*pb++);
emh203 0:3d9c67d97d6f 135
emh203 0:3d9c67d97d6f 136 /* acc += b[N-1] * x[n-N-1] */
emh203 0:3d9c67d97d6f 137 acc += ((q63_t) (*px++)) * (*pb++);
emh203 0:3d9c67d97d6f 138
emh203 0:3d9c67d97d6f 139 /* acc += b[N-2] * x[n-N-2] */
emh203 0:3d9c67d97d6f 140 acc += ((q63_t) (*px++)) * (*pb++);
emh203 0:3d9c67d97d6f 141
emh203 0:3d9c67d97d6f 142 /* acc += b[N-3] * x[n-N-3] */
emh203 0:3d9c67d97d6f 143 acc += ((q63_t) (*px++)) * (*pb++);
emh203 0:3d9c67d97d6f 144
emh203 0:3d9c67d97d6f 145 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 146 tapCnt--;
emh203 0:3d9c67d97d6f 147 }
emh203 0:3d9c67d97d6f 148
emh203 0:3d9c67d97d6f 149 /* If the filter length is not a multiple of 4, compute the remaining filter taps */
emh203 0:3d9c67d97d6f 150 tapCnt = numTaps % 0x4u;
emh203 0:3d9c67d97d6f 151
emh203 0:3d9c67d97d6f 152 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 153 {
emh203 0:3d9c67d97d6f 154 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 155 acc += ((q63_t) (*px++)) * (*pb++);
emh203 0:3d9c67d97d6f 156
emh203 0:3d9c67d97d6f 157 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 158 tapCnt--;
emh203 0:3d9c67d97d6f 159 }
emh203 0:3d9c67d97d6f 160
emh203 0:3d9c67d97d6f 161 /* Converting the result to 1.31 format */
emh203 0:3d9c67d97d6f 162 /* Calc lower part of acc */
emh203 0:3d9c67d97d6f 163 acc_l = acc & 0xffffffff;
emh203 0:3d9c67d97d6f 164
emh203 0:3d9c67d97d6f 165 /* Calc upper part of acc */
emh203 0:3d9c67d97d6f 166 acc_h = (acc >> 32) & 0xffffffff;
emh203 0:3d9c67d97d6f 167
emh203 0:3d9c67d97d6f 168 acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
emh203 0:3d9c67d97d6f 169
emh203 0:3d9c67d97d6f 170 /* Store the result from accumulator into the destination buffer. */
emh203 0:3d9c67d97d6f 171 *pOut++ = (q31_t) acc;
emh203 0:3d9c67d97d6f 172
emh203 0:3d9c67d97d6f 173 /* Compute and store error */
emh203 0:3d9c67d97d6f 174 e = *pRef++ - (q31_t) acc;
emh203 0:3d9c67d97d6f 175
emh203 0:3d9c67d97d6f 176 *pErr++ = (q31_t) e;
emh203 0:3d9c67d97d6f 177
emh203 0:3d9c67d97d6f 178 /* Compute alpha i.e. intermediate constant for taps update */
emh203 0:3d9c67d97d6f 179 alpha = (q31_t) (((q63_t) e * mu) >> 31);
emh203 0:3d9c67d97d6f 180
emh203 0:3d9c67d97d6f 181 /* Initialize state pointer */
emh203 0:3d9c67d97d6f 182 /* Advance state pointer by 1 for the next sample */
emh203 0:3d9c67d97d6f 183 px = pState++;
emh203 0:3d9c67d97d6f 184
emh203 0:3d9c67d97d6f 185 /* Initialize coefficient pointer */
emh203 0:3d9c67d97d6f 186 pb = pCoeffs;
emh203 0:3d9c67d97d6f 187
emh203 0:3d9c67d97d6f 188 /* Loop unrolling. Process 4 taps at a time. */
emh203 0:3d9c67d97d6f 189 tapCnt = numTaps >> 2;
emh203 0:3d9c67d97d6f 190
emh203 0:3d9c67d97d6f 191 /* Update filter coefficients */
emh203 0:3d9c67d97d6f 192 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 193 {
emh203 0:3d9c67d97d6f 194 /* coef is in 2.30 format */
emh203 0:3d9c67d97d6f 195 coef = (q31_t) (((q63_t) alpha * (*px++)) >> (32));
emh203 0:3d9c67d97d6f 196 /* get coef in 1.31 format by left shifting */
emh203 0:3d9c67d97d6f 197 *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
emh203 0:3d9c67d97d6f 198 /* update coefficient buffer to next coefficient */
emh203 0:3d9c67d97d6f 199 pb++;
emh203 0:3d9c67d97d6f 200
emh203 0:3d9c67d97d6f 201 coef = (q31_t) (((q63_t) alpha * (*px++)) >> (32));
emh203 0:3d9c67d97d6f 202 *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
emh203 0:3d9c67d97d6f 203 pb++;
emh203 0:3d9c67d97d6f 204
emh203 0:3d9c67d97d6f 205 coef = (q31_t) (((q63_t) alpha * (*px++)) >> (32));
emh203 0:3d9c67d97d6f 206 *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
emh203 0:3d9c67d97d6f 207 pb++;
emh203 0:3d9c67d97d6f 208
emh203 0:3d9c67d97d6f 209 coef = (q31_t) (((q63_t) alpha * (*px++)) >> (32));
emh203 0:3d9c67d97d6f 210 *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
emh203 0:3d9c67d97d6f 211 pb++;
emh203 0:3d9c67d97d6f 212
emh203 0:3d9c67d97d6f 213 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 214 tapCnt--;
emh203 0:3d9c67d97d6f 215 }
emh203 0:3d9c67d97d6f 216
emh203 0:3d9c67d97d6f 217 /* If the filter length is not a multiple of 4, compute the remaining filter taps */
emh203 0:3d9c67d97d6f 218 tapCnt = numTaps % 0x4u;
emh203 0:3d9c67d97d6f 219
emh203 0:3d9c67d97d6f 220 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 221 {
emh203 0:3d9c67d97d6f 222 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 223 coef = (q31_t) (((q63_t) alpha * (*px++)) >> (32));
emh203 0:3d9c67d97d6f 224 *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
emh203 0:3d9c67d97d6f 225 pb++;
emh203 0:3d9c67d97d6f 226
emh203 0:3d9c67d97d6f 227 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 228 tapCnt--;
emh203 0:3d9c67d97d6f 229 }
emh203 0:3d9c67d97d6f 230
emh203 0:3d9c67d97d6f 231 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 232 blkCnt--;
emh203 0:3d9c67d97d6f 233 }
emh203 0:3d9c67d97d6f 234
emh203 0:3d9c67d97d6f 235 /* Processing is complete. Now copy the last numTaps - 1 samples to the
emh203 0:3d9c67d97d6f 236 satrt of the state buffer. This prepares the state buffer for the
emh203 0:3d9c67d97d6f 237 next function call. */
emh203 0:3d9c67d97d6f 238
emh203 0:3d9c67d97d6f 239 /* Points to the start of the pState buffer */
emh203 0:3d9c67d97d6f 240 pStateCurnt = S->pState;
emh203 0:3d9c67d97d6f 241
emh203 0:3d9c67d97d6f 242 /* Loop unrolling for (numTaps - 1u) samples copy */
emh203 0:3d9c67d97d6f 243 tapCnt = (numTaps - 1u) >> 2u;
emh203 0:3d9c67d97d6f 244
emh203 0:3d9c67d97d6f 245 /* copy data */
emh203 0:3d9c67d97d6f 246 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 247 {
emh203 0:3d9c67d97d6f 248 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 249 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 250 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 251 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 252
emh203 0:3d9c67d97d6f 253 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 254 tapCnt--;
emh203 0:3d9c67d97d6f 255 }
emh203 0:3d9c67d97d6f 256
emh203 0:3d9c67d97d6f 257 /* Calculate remaining number of copies */
emh203 0:3d9c67d97d6f 258 tapCnt = (numTaps - 1u) % 0x4u;
emh203 0:3d9c67d97d6f 259
emh203 0:3d9c67d97d6f 260 /* Copy the remaining q31_t data */
emh203 0:3d9c67d97d6f 261 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 262 {
emh203 0:3d9c67d97d6f 263 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 264
emh203 0:3d9c67d97d6f 265 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 266 tapCnt--;
emh203 0:3d9c67d97d6f 267 }
emh203 0:3d9c67d97d6f 268
emh203 0:3d9c67d97d6f 269 #else
emh203 0:3d9c67d97d6f 270
emh203 0:3d9c67d97d6f 271 /* Run the below code for Cortex-M0 */
emh203 0:3d9c67d97d6f 272
emh203 0:3d9c67d97d6f 273 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 274 {
emh203 0:3d9c67d97d6f 275 /* Copy the new input sample into the state buffer */
emh203 0:3d9c67d97d6f 276 *pStateCurnt++ = *pSrc++;
emh203 0:3d9c67d97d6f 277
emh203 0:3d9c67d97d6f 278 /* Initialize pState pointer */
emh203 0:3d9c67d97d6f 279 px = pState;
emh203 0:3d9c67d97d6f 280
emh203 0:3d9c67d97d6f 281 /* Initialize pCoeffs pointer */
emh203 0:3d9c67d97d6f 282 pb = pCoeffs;
emh203 0:3d9c67d97d6f 283
emh203 0:3d9c67d97d6f 284 /* Set the accumulator to zero */
emh203 0:3d9c67d97d6f 285 acc = 0;
emh203 0:3d9c67d97d6f 286
emh203 0:3d9c67d97d6f 287 /* Loop over numTaps number of values */
emh203 0:3d9c67d97d6f 288 tapCnt = numTaps;
emh203 0:3d9c67d97d6f 289
emh203 0:3d9c67d97d6f 290 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 291 {
emh203 0:3d9c67d97d6f 292 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 293 acc += ((q63_t) (*px++)) * (*pb++);
emh203 0:3d9c67d97d6f 294
emh203 0:3d9c67d97d6f 295 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 296 tapCnt--;
emh203 0:3d9c67d97d6f 297 }
emh203 0:3d9c67d97d6f 298
emh203 0:3d9c67d97d6f 299 /* Converting the result to 1.31 format */
emh203 0:3d9c67d97d6f 300 /* Store the result from accumulator into the destination buffer. */
emh203 0:3d9c67d97d6f 301 /* Calc lower part of acc */
emh203 0:3d9c67d97d6f 302 acc_l = acc & 0xffffffff;
emh203 0:3d9c67d97d6f 303
emh203 0:3d9c67d97d6f 304 /* Calc upper part of acc */
emh203 0:3d9c67d97d6f 305 acc_h = (acc >> 32) & 0xffffffff;
emh203 0:3d9c67d97d6f 306
emh203 0:3d9c67d97d6f 307 acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
emh203 0:3d9c67d97d6f 308
emh203 0:3d9c67d97d6f 309 *pOut++ = (q31_t) acc;
emh203 0:3d9c67d97d6f 310
emh203 0:3d9c67d97d6f 311 /* Compute and store error */
emh203 0:3d9c67d97d6f 312 e = *pRef++ - (q31_t) acc;
emh203 0:3d9c67d97d6f 313
emh203 0:3d9c67d97d6f 314 *pErr++ = (q31_t) e;
emh203 0:3d9c67d97d6f 315
emh203 0:3d9c67d97d6f 316 /* Weighting factor for the LMS version */
emh203 0:3d9c67d97d6f 317 alpha = (q31_t) (((q63_t) e * mu) >> 31);
emh203 0:3d9c67d97d6f 318
emh203 0:3d9c67d97d6f 319 /* Initialize pState pointer */
emh203 0:3d9c67d97d6f 320 /* Advance state pointer by 1 for the next sample */
emh203 0:3d9c67d97d6f 321 px = pState++;
emh203 0:3d9c67d97d6f 322
emh203 0:3d9c67d97d6f 323 /* Initialize pCoeffs pointer */
emh203 0:3d9c67d97d6f 324 pb = pCoeffs;
emh203 0:3d9c67d97d6f 325
emh203 0:3d9c67d97d6f 326 /* Loop over numTaps number of values */
emh203 0:3d9c67d97d6f 327 tapCnt = numTaps;
emh203 0:3d9c67d97d6f 328
emh203 0:3d9c67d97d6f 329 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 330 {
emh203 0:3d9c67d97d6f 331 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 332 coef = (q31_t) (((q63_t) alpha * (*px++)) >> (32));
emh203 0:3d9c67d97d6f 333 *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
emh203 0:3d9c67d97d6f 334 pb++;
emh203 0:3d9c67d97d6f 335
emh203 0:3d9c67d97d6f 336 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 337 tapCnt--;
emh203 0:3d9c67d97d6f 338 }
emh203 0:3d9c67d97d6f 339
emh203 0:3d9c67d97d6f 340 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 341 blkCnt--;
emh203 0:3d9c67d97d6f 342 }
emh203 0:3d9c67d97d6f 343
emh203 0:3d9c67d97d6f 344 /* Processing is complete. Now copy the last numTaps - 1 samples to the
emh203 0:3d9c67d97d6f 345 start of the state buffer. This prepares the state buffer for the
emh203 0:3d9c67d97d6f 346 next function call. */
emh203 0:3d9c67d97d6f 347
emh203 0:3d9c67d97d6f 348 /* Points to the start of the pState buffer */
emh203 0:3d9c67d97d6f 349 pStateCurnt = S->pState;
emh203 0:3d9c67d97d6f 350
emh203 0:3d9c67d97d6f 351 /* Copy (numTaps - 1u) samples */
emh203 0:3d9c67d97d6f 352 tapCnt = (numTaps - 1u);
emh203 0:3d9c67d97d6f 353
emh203 0:3d9c67d97d6f 354 /* Copy the data */
emh203 0:3d9c67d97d6f 355 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 356 {
emh203 0:3d9c67d97d6f 357 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 358
emh203 0:3d9c67d97d6f 359 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 360 tapCnt--;
emh203 0:3d9c67d97d6f 361 }
emh203 0:3d9c67d97d6f 362
emh203 0:3d9c67d97d6f 363 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
emh203 0:3d9c67d97d6f 364
emh203 0:3d9c67d97d6f 365 }
emh203 0:3d9c67d97d6f 366
emh203 0:3d9c67d97d6f 367 /**
emh203 0:3d9c67d97d6f 368 * @} end of LMS group
emh203 0:3d9c67d97d6f 369 */