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CMSIS DSP library

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cmsis_dsp/FilteringFunctions/arm_lms_norm_q15.c@2:da51fb522205, 2013-05-30 (annotated)

Committer:
emilmont
Date:
Thu May 30 17:10:11 2013 +0100
Revision:
2:da51fb522205
Parent:
1:fdd22bb7aa52
Child:
3:7a284390b0ce
Keep "cmsis-dsp" module in synch with its source

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
emilmont 1:fdd22bb7aa52 2 * Copyright (C) 2010 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
emilmont 1:fdd22bb7aa52 4 * $Date: 15. February 2012
emilmont 2:da51fb522205 5 * $Revision: V1.1.0
emilmont 1:fdd22bb7aa52 6 *
emilmont 2:da51fb522205 7 * Project: CMSIS DSP Library
emilmont 2:da51fb522205 8 * Title: arm_lms_norm_q15.c
emilmont 1:fdd22bb7aa52 9 *
emilmont 2:da51fb522205 10 * Description: Q15 NLMS filter.
emilmont 1:fdd22bb7aa52 11 *
emilmont 1:fdd22bb7aa52 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
emilmont 1:fdd22bb7aa52 13 *
emilmont 1:fdd22bb7aa52 14 * Version 1.1.0 2012/02/15
emilmont 1:fdd22bb7aa52 15 * Updated with more optimizations, bug fixes and minor API changes.
emilmont 1:fdd22bb7aa52 16 *
emilmont 1:fdd22bb7aa52 17 * Version 1.0.10 2011/7/15
emilmont 1:fdd22bb7aa52 18 * Big Endian support added and Merged M0 and M3/M4 Source code.
emilmont 1:fdd22bb7aa52 19 *
emilmont 1:fdd22bb7aa52 20 * Version 1.0.3 2010/11/29
emilmont 1:fdd22bb7aa52 21 * Re-organized the CMSIS folders and updated documentation.
emilmont 1:fdd22bb7aa52 22 *
emilmont 1:fdd22bb7aa52 23 * Version 1.0.2 2010/11/11
emilmont 1:fdd22bb7aa52 24 * Documentation updated.
emilmont 1:fdd22bb7aa52 25 *
emilmont 1:fdd22bb7aa52 26 * Version 1.0.1 2010/10/05
emilmont 1:fdd22bb7aa52 27 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 28 *
emilmont 1:fdd22bb7aa52 29 * Version 1.0.0 2010/09/20
emilmont 1:fdd22bb7aa52 30 * Production release and review comments incorporated
emilmont 1:fdd22bb7aa52 31 *
emilmont 1:fdd22bb7aa52 32 * Version 0.0.7 2010/06/10
emilmont 1:fdd22bb7aa52 33 * Misra-C changes done
emilmont 1:fdd22bb7aa52 34 * -------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 35
emilmont 1:fdd22bb7aa52 36 #include "arm_math.h"
emilmont 1:fdd22bb7aa52 37
emilmont 1:fdd22bb7aa52 38 /**
emilmont 1:fdd22bb7aa52 39 * @ingroup groupFilters
emilmont 1:fdd22bb7aa52 40 */
emilmont 1:fdd22bb7aa52 41
emilmont 1:fdd22bb7aa52 42 /**
emilmont 1:fdd22bb7aa52 43 * @addtogroup LMS_NORM
emilmont 1:fdd22bb7aa52 44 * @{
emilmont 1:fdd22bb7aa52 45 */
emilmont 1:fdd22bb7aa52 46
emilmont 1:fdd22bb7aa52 47 /**
emilmont 1:fdd22bb7aa52 48 * @brief Processing function for Q15 normalized LMS filter.
emilmont 1:fdd22bb7aa52 49 * @param[in] *S points to an instance of the Q15 normalized LMS filter structure.
emilmont 1:fdd22bb7aa52 50 * @param[in] *pSrc points to the block of input data.
emilmont 1:fdd22bb7aa52 51 * @param[in] *pRef points to the block of reference data.
emilmont 1:fdd22bb7aa52 52 * @param[out] *pOut points to the block of output data.
emilmont 1:fdd22bb7aa52 53 * @param[out] *pErr points to the block of error data.
emilmont 1:fdd22bb7aa52 54 * @param[in] blockSize number of samples to process.
emilmont 1:fdd22bb7aa52 55 * @return none.
emilmont 1:fdd22bb7aa52 56 *
emilmont 1:fdd22bb7aa52 57 * <b>Scaling and Overflow Behavior:</b>
emilmont 1:fdd22bb7aa52 58 * \par
emilmont 1:fdd22bb7aa52 59 * The function is implemented using a 64-bit internal accumulator.
emilmont 1:fdd22bb7aa52 60 * Both coefficients and state variables are represented in 1.15 format and
emilmont 1:fdd22bb7aa52 61 * multiplications yield a 2.30 result. The 2.30 intermediate results are
emilmont 1:fdd22bb7aa52 62 * accumulated in a 64-bit accumulator in 34.30 format.
emilmont 1:fdd22bb7aa52 63 * There is no risk of internal overflow with this approach and the full
emilmont 1:fdd22bb7aa52 64 * precision of intermediate multiplications is preserved. After all additions
emilmont 1:fdd22bb7aa52 65 * have been performed, the accumulator is truncated to 34.15 format by
emilmont 1:fdd22bb7aa52 66 * discarding low 15 bits. Lastly, the accumulator is saturated to yield a
emilmont 1:fdd22bb7aa52 67 * result in 1.15 format.
emilmont 1:fdd22bb7aa52 68 *
emilmont 1:fdd22bb7aa52 69 * \par
emilmont 2:da51fb522205 70 * In this filter, filter coefficients are updated for each sample and the updation of filter cofficients are saturted.
emilmont 1:fdd22bb7aa52 71 *
emilmont 1:fdd22bb7aa52 72 */
emilmont 1:fdd22bb7aa52 73
emilmont 1:fdd22bb7aa52 74 void arm_lms_norm_q15(
emilmont 1:fdd22bb7aa52 75 arm_lms_norm_instance_q15 * S,
emilmont 1:fdd22bb7aa52 76 q15_t * pSrc,
emilmont 1:fdd22bb7aa52 77 q15_t * pRef,
emilmont 1:fdd22bb7aa52 78 q15_t * pOut,
emilmont 1:fdd22bb7aa52 79 q15_t * pErr,
emilmont 1:fdd22bb7aa52 80 uint32_t blockSize)
emilmont 1:fdd22bb7aa52 81 {
emilmont 1:fdd22bb7aa52 82 q15_t *pState = S->pState; /* State pointer */
emilmont 1:fdd22bb7aa52 83 q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
emilmont 1:fdd22bb7aa52 84 q15_t *pStateCurnt; /* Points to the current sample of the state */
emilmont 1:fdd22bb7aa52 85 q15_t *px, *pb; /* Temporary pointers for state and coefficient buffers */
emilmont 1:fdd22bb7aa52 86 q15_t mu = S->mu; /* Adaptive factor */
emilmont 1:fdd22bb7aa52 87 uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
emilmont 1:fdd22bb7aa52 88 uint32_t tapCnt, blkCnt; /* Loop counters */
emilmont 1:fdd22bb7aa52 89 q31_t energy; /* Energy of the input */
emilmont 1:fdd22bb7aa52 90 q63_t acc; /* Accumulator */
emilmont 1:fdd22bb7aa52 91 q15_t e = 0, d = 0; /* error, reference data sample */
emilmont 1:fdd22bb7aa52 92 q15_t w = 0, in; /* weight factor and state */
emilmont 1:fdd22bb7aa52 93 q15_t x0; /* temporary variable to hold input sample */
emilmont 1:fdd22bb7aa52 94 //uint32_t shift = (uint32_t) S->postShift + 1u; /* Shift to be applied to the output */
emilmont 1:fdd22bb7aa52 95 q15_t errorXmu, oneByEnergy; /* Temporary variables to store error and mu product and reciprocal of energy */
emilmont 1:fdd22bb7aa52 96 q15_t postShift; /* Post shift to be applied to weight after reciprocal calculation */
emilmont 1:fdd22bb7aa52 97 q31_t coef; /* Teporary variable for coefficient */
emilmont 1:fdd22bb7aa52 98 q31_t acc_l, acc_h;
emilmont 1:fdd22bb7aa52 99 int32_t lShift = (15 - (int32_t) S->postShift); /* Post shift */
emilmont 1:fdd22bb7aa52 100 int32_t uShift = (32 - lShift);
emilmont 1:fdd22bb7aa52 101
emilmont 1:fdd22bb7aa52 102 energy = S->energy;
emilmont 1:fdd22bb7aa52 103 x0 = S->x0;
emilmont 1:fdd22bb7aa52 104
emilmont 1:fdd22bb7aa52 105 /* S->pState points to buffer which contains previous frame (numTaps - 1) samples */
emilmont 1:fdd22bb7aa52 106 /* pStateCurnt points to the location where the new input data should be written */
emilmont 1:fdd22bb7aa52 107 pStateCurnt = &(S->pState[(numTaps - 1u)]);
emilmont 1:fdd22bb7aa52 108
emilmont 1:fdd22bb7aa52 109 /* Loop over blockSize number of values */
emilmont 1:fdd22bb7aa52 110 blkCnt = blockSize;
emilmont 1:fdd22bb7aa52 111
emilmont 1:fdd22bb7aa52 112
emilmont 1:fdd22bb7aa52 113 #ifndef ARM_MATH_CM0
emilmont 1:fdd22bb7aa52 114
emilmont 1:fdd22bb7aa52 115 /* Run the below code for Cortex-M4 and Cortex-M3 */
emilmont 1:fdd22bb7aa52 116
emilmont 1:fdd22bb7aa52 117 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 118 {
emilmont 1:fdd22bb7aa52 119 /* Copy the new input sample into the state buffer */
emilmont 1:fdd22bb7aa52 120 *pStateCurnt++ = *pSrc;
emilmont 1:fdd22bb7aa52 121
emilmont 1:fdd22bb7aa52 122 /* Initialize pState pointer */
emilmont 1:fdd22bb7aa52 123 px = pState;
emilmont 1:fdd22bb7aa52 124
emilmont 1:fdd22bb7aa52 125 /* Initialize coeff pointer */
emilmont 1:fdd22bb7aa52 126 pb = (pCoeffs);
emilmont 1:fdd22bb7aa52 127
emilmont 1:fdd22bb7aa52 128 /* Read the sample from input buffer */
emilmont 1:fdd22bb7aa52 129 in = *pSrc++;
emilmont 1:fdd22bb7aa52 130
emilmont 1:fdd22bb7aa52 131 /* Update the energy calculation */
emilmont 1:fdd22bb7aa52 132 energy -= (((q31_t) x0 * (x0)) >> 15);
emilmont 1:fdd22bb7aa52 133 energy += (((q31_t) in * (in)) >> 15);
emilmont 1:fdd22bb7aa52 134
emilmont 1:fdd22bb7aa52 135 /* Set the accumulator to zero */
emilmont 1:fdd22bb7aa52 136 acc = 0;
emilmont 1:fdd22bb7aa52 137
emilmont 1:fdd22bb7aa52 138 /* Loop unrolling. Process 4 taps at a time. */
emilmont 1:fdd22bb7aa52 139 tapCnt = numTaps >> 2;
emilmont 1:fdd22bb7aa52 140
emilmont 1:fdd22bb7aa52 141 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 142 {
emilmont 1:fdd22bb7aa52 143
emilmont 1:fdd22bb7aa52 144 /* Perform the multiply-accumulate */
emilmont 1:fdd22bb7aa52 145 #ifndef UNALIGNED_SUPPORT_DISABLE
emilmont 1:fdd22bb7aa52 146
emilmont 1:fdd22bb7aa52 147 acc = __SMLALD(*__SIMD32(px)++, (*__SIMD32(pb)++), acc);
emilmont 1:fdd22bb7aa52 148 acc = __SMLALD(*__SIMD32(px)++, (*__SIMD32(pb)++), acc);
emilmont 1:fdd22bb7aa52 149
emilmont 1:fdd22bb7aa52 150 #else
emilmont 1:fdd22bb7aa52 151
emilmont 1:fdd22bb7aa52 152 acc += (((q31_t) * px++ * (*pb++)));
emilmont 1:fdd22bb7aa52 153 acc += (((q31_t) * px++ * (*pb++)));
emilmont 1:fdd22bb7aa52 154 acc += (((q31_t) * px++ * (*pb++)));
emilmont 1:fdd22bb7aa52 155 acc += (((q31_t) * px++ * (*pb++)));
emilmont 1:fdd22bb7aa52 156
emilmont 2:da51fb522205 157 #endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */
emilmont 1:fdd22bb7aa52 158
emilmont 1:fdd22bb7aa52 159 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 160 tapCnt--;
emilmont 1:fdd22bb7aa52 161 }
emilmont 1:fdd22bb7aa52 162
emilmont 1:fdd22bb7aa52 163 /* If the filter length is not a multiple of 4, compute the remaining filter taps */
emilmont 1:fdd22bb7aa52 164 tapCnt = numTaps % 0x4u;
emilmont 1:fdd22bb7aa52 165
emilmont 1:fdd22bb7aa52 166 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 167 {
emilmont 1:fdd22bb7aa52 168 /* Perform the multiply-accumulate */
emilmont 1:fdd22bb7aa52 169 acc += (((q31_t) * px++ * (*pb++)));
emilmont 1:fdd22bb7aa52 170
emilmont 1:fdd22bb7aa52 171 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 172 tapCnt--;
emilmont 1:fdd22bb7aa52 173 }
emilmont 1:fdd22bb7aa52 174
emilmont 1:fdd22bb7aa52 175 /* Calc lower part of acc */
emilmont 1:fdd22bb7aa52 176 acc_l = acc & 0xffffffff;
emilmont 1:fdd22bb7aa52 177
emilmont 1:fdd22bb7aa52 178 /* Calc upper part of acc */
emilmont 1:fdd22bb7aa52 179 acc_h = (acc >> 32) & 0xffffffff;
emilmont 1:fdd22bb7aa52 180
emilmont 1:fdd22bb7aa52 181 /* Apply shift for lower part of acc and upper part of acc */
emilmont 1:fdd22bb7aa52 182 acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
emilmont 1:fdd22bb7aa52 183
emilmont 1:fdd22bb7aa52 184 /* Converting the result to 1.15 format and saturate the output */
emilmont 1:fdd22bb7aa52 185 acc = __SSAT(acc, 16u);
emilmont 1:fdd22bb7aa52 186
emilmont 1:fdd22bb7aa52 187 /* Store the result from accumulator into the destination buffer. */
emilmont 1:fdd22bb7aa52 188 *pOut++ = (q15_t) acc;
emilmont 1:fdd22bb7aa52 189
emilmont 1:fdd22bb7aa52 190 /* Compute and store error */
emilmont 1:fdd22bb7aa52 191 d = *pRef++;
emilmont 1:fdd22bb7aa52 192 e = d - (q15_t) acc;
emilmont 1:fdd22bb7aa52 193 *pErr++ = e;
emilmont 1:fdd22bb7aa52 194
emilmont 1:fdd22bb7aa52 195 /* Calculation of 1/energy */
emilmont 1:fdd22bb7aa52 196 postShift = arm_recip_q15((q15_t) energy + DELTA_Q15,
emilmont 1:fdd22bb7aa52 197 &oneByEnergy, S->recipTable);
emilmont 1:fdd22bb7aa52 198
emilmont 1:fdd22bb7aa52 199 /* Calculation of e * mu value */
emilmont 1:fdd22bb7aa52 200 errorXmu = (q15_t) (((q31_t) e * mu) >> 15);
emilmont 1:fdd22bb7aa52 201
emilmont 1:fdd22bb7aa52 202 /* Calculation of (e * mu) * (1/energy) value */
emilmont 1:fdd22bb7aa52 203 acc = (((q31_t) errorXmu * oneByEnergy) >> (15 - postShift));
emilmont 1:fdd22bb7aa52 204
emilmont 1:fdd22bb7aa52 205 /* Weighting factor for the normalized version */
emilmont 1:fdd22bb7aa52 206 w = (q15_t) __SSAT((q31_t) acc, 16);
emilmont 1:fdd22bb7aa52 207
emilmont 1:fdd22bb7aa52 208 /* Initialize pState pointer */
emilmont 1:fdd22bb7aa52 209 px = pState;
emilmont 1:fdd22bb7aa52 210
emilmont 1:fdd22bb7aa52 211 /* Initialize coeff pointer */
emilmont 1:fdd22bb7aa52 212 pb = (pCoeffs);
emilmont 1:fdd22bb7aa52 213
emilmont 1:fdd22bb7aa52 214 /* Loop unrolling. Process 4 taps at a time. */
emilmont 1:fdd22bb7aa52 215 tapCnt = numTaps >> 2;
emilmont 1:fdd22bb7aa52 216
emilmont 1:fdd22bb7aa52 217 /* Update filter coefficients */
emilmont 1:fdd22bb7aa52 218 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 219 {
emilmont 1:fdd22bb7aa52 220 coef = *pb + (((q31_t) w * (*px++)) >> 15);
emilmont 1:fdd22bb7aa52 221 *pb++ = (q15_t) __SSAT((coef), 16);
emilmont 1:fdd22bb7aa52 222 coef = *pb + (((q31_t) w * (*px++)) >> 15);
emilmont 1:fdd22bb7aa52 223 *pb++ = (q15_t) __SSAT((coef), 16);
emilmont 1:fdd22bb7aa52 224 coef = *pb + (((q31_t) w * (*px++)) >> 15);
emilmont 1:fdd22bb7aa52 225 *pb++ = (q15_t) __SSAT((coef), 16);
emilmont 1:fdd22bb7aa52 226 coef = *pb + (((q31_t) w * (*px++)) >> 15);
emilmont 1:fdd22bb7aa52 227 *pb++ = (q15_t) __SSAT((coef), 16);
emilmont 1:fdd22bb7aa52 228
emilmont 1:fdd22bb7aa52 229 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 230 tapCnt--;
emilmont 1:fdd22bb7aa52 231 }
emilmont 1:fdd22bb7aa52 232
emilmont 1:fdd22bb7aa52 233 /* If the filter length is not a multiple of 4, compute the remaining filter taps */
emilmont 1:fdd22bb7aa52 234 tapCnt = numTaps % 0x4u;
emilmont 1:fdd22bb7aa52 235
emilmont 1:fdd22bb7aa52 236 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 237 {
emilmont 1:fdd22bb7aa52 238 /* Perform the multiply-accumulate */
emilmont 1:fdd22bb7aa52 239 coef = *pb + (((q31_t) w * (*px++)) >> 15);
emilmont 1:fdd22bb7aa52 240 *pb++ = (q15_t) __SSAT((coef), 16);
emilmont 1:fdd22bb7aa52 241
emilmont 1:fdd22bb7aa52 242 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 243 tapCnt--;
emilmont 1:fdd22bb7aa52 244 }
emilmont 1:fdd22bb7aa52 245
emilmont 1:fdd22bb7aa52 246 /* Read the sample from state buffer */
emilmont 1:fdd22bb7aa52 247 x0 = *pState;
emilmont 1:fdd22bb7aa52 248
emilmont 1:fdd22bb7aa52 249 /* Advance state pointer by 1 for the next sample */
emilmont 1:fdd22bb7aa52 250 pState = pState + 1u;
emilmont 1:fdd22bb7aa52 251
emilmont 1:fdd22bb7aa52 252 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 253 blkCnt--;
emilmont 1:fdd22bb7aa52 254 }
emilmont 1:fdd22bb7aa52 255
emilmont 1:fdd22bb7aa52 256 /* Save energy and x0 values for the next frame */
emilmont 1:fdd22bb7aa52 257 S->energy = (q15_t) energy;
emilmont 1:fdd22bb7aa52 258 S->x0 = x0;
emilmont 1:fdd22bb7aa52 259
emilmont 1:fdd22bb7aa52 260 /* Processing is complete. Now copy the last numTaps - 1 samples to the
emilmont 1:fdd22bb7aa52 261 satrt of the state buffer. This prepares the state buffer for the
emilmont 1:fdd22bb7aa52 262 next function call. */
emilmont 1:fdd22bb7aa52 263
emilmont 1:fdd22bb7aa52 264 /* Points to the start of the pState buffer */
emilmont 1:fdd22bb7aa52 265 pStateCurnt = S->pState;
emilmont 1:fdd22bb7aa52 266
emilmont 1:fdd22bb7aa52 267 /* Calculation of count for copying integer writes */
emilmont 1:fdd22bb7aa52 268 tapCnt = (numTaps - 1u) >> 2;
emilmont 1:fdd22bb7aa52 269
emilmont 1:fdd22bb7aa52 270 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 271 {
emilmont 1:fdd22bb7aa52 272
emilmont 1:fdd22bb7aa52 273 #ifndef UNALIGNED_SUPPORT_DISABLE
emilmont 1:fdd22bb7aa52 274
emilmont 1:fdd22bb7aa52 275 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
emilmont 1:fdd22bb7aa52 276 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
emilmont 1:fdd22bb7aa52 277
emilmont 1:fdd22bb7aa52 278 #else
emilmont 1:fdd22bb7aa52 279
emilmont 1:fdd22bb7aa52 280 *pStateCurnt++ = *pState++;
emilmont 1:fdd22bb7aa52 281 *pStateCurnt++ = *pState++;
emilmont 1:fdd22bb7aa52 282 *pStateCurnt++ = *pState++;
emilmont 1:fdd22bb7aa52 283 *pStateCurnt++ = *pState++;
emilmont 1:fdd22bb7aa52 284
emilmont 1:fdd22bb7aa52 285 #endif
emilmont 1:fdd22bb7aa52 286
emilmont 1:fdd22bb7aa52 287 tapCnt--;
emilmont 1:fdd22bb7aa52 288
emilmont 1:fdd22bb7aa52 289 }
emilmont 1:fdd22bb7aa52 290
emilmont 1:fdd22bb7aa52 291 /* Calculation of count for remaining q15_t data */
emilmont 1:fdd22bb7aa52 292 tapCnt = (numTaps - 1u) % 0x4u;
emilmont 1:fdd22bb7aa52 293
emilmont 1:fdd22bb7aa52 294 /* copy data */
emilmont 1:fdd22bb7aa52 295 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 296 {
emilmont 1:fdd22bb7aa52 297 *pStateCurnt++ = *pState++;
emilmont 1:fdd22bb7aa52 298
emilmont 1:fdd22bb7aa52 299 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 300 tapCnt--;
emilmont 1:fdd22bb7aa52 301 }
emilmont 1:fdd22bb7aa52 302
emilmont 1:fdd22bb7aa52 303 #else
emilmont 1:fdd22bb7aa52 304
emilmont 1:fdd22bb7aa52 305 /* Run the below code for Cortex-M0 */
emilmont 1:fdd22bb7aa52 306
emilmont 1:fdd22bb7aa52 307 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 308 {
emilmont 1:fdd22bb7aa52 309 /* Copy the new input sample into the state buffer */
emilmont 1:fdd22bb7aa52 310 *pStateCurnt++ = *pSrc;
emilmont 1:fdd22bb7aa52 311
emilmont 1:fdd22bb7aa52 312 /* Initialize pState pointer */
emilmont 1:fdd22bb7aa52 313 px = pState;
emilmont 1:fdd22bb7aa52 314
emilmont 1:fdd22bb7aa52 315 /* Initialize pCoeffs pointer */
emilmont 1:fdd22bb7aa52 316 pb = pCoeffs;
emilmont 1:fdd22bb7aa52 317
emilmont 1:fdd22bb7aa52 318 /* Read the sample from input buffer */
emilmont 1:fdd22bb7aa52 319 in = *pSrc++;
emilmont 1:fdd22bb7aa52 320
emilmont 1:fdd22bb7aa52 321 /* Update the energy calculation */
emilmont 1:fdd22bb7aa52 322 energy -= (((q31_t) x0 * (x0)) >> 15);
emilmont 1:fdd22bb7aa52 323 energy += (((q31_t) in * (in)) >> 15);
emilmont 1:fdd22bb7aa52 324
emilmont 1:fdd22bb7aa52 325 /* Set the accumulator to zero */
emilmont 1:fdd22bb7aa52 326 acc = 0;
emilmont 1:fdd22bb7aa52 327
emilmont 1:fdd22bb7aa52 328 /* Loop over numTaps number of values */
emilmont 1:fdd22bb7aa52 329 tapCnt = numTaps;
emilmont 1:fdd22bb7aa52 330
emilmont 1:fdd22bb7aa52 331 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 332 {
emilmont 1:fdd22bb7aa52 333 /* Perform the multiply-accumulate */
emilmont 1:fdd22bb7aa52 334 acc += (((q31_t) * px++ * (*pb++)));
emilmont 1:fdd22bb7aa52 335
emilmont 1:fdd22bb7aa52 336 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 337 tapCnt--;
emilmont 1:fdd22bb7aa52 338 }
emilmont 1:fdd22bb7aa52 339
emilmont 1:fdd22bb7aa52 340 /* Calc lower part of acc */
emilmont 1:fdd22bb7aa52 341 acc_l = acc & 0xffffffff;
emilmont 1:fdd22bb7aa52 342
emilmont 1:fdd22bb7aa52 343 /* Calc upper part of acc */
emilmont 1:fdd22bb7aa52 344 acc_h = (acc >> 32) & 0xffffffff;
emilmont 1:fdd22bb7aa52 345
emilmont 1:fdd22bb7aa52 346 /* Apply shift for lower part of acc and upper part of acc */
emilmont 1:fdd22bb7aa52 347 acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
emilmont 1:fdd22bb7aa52 348
emilmont 1:fdd22bb7aa52 349 /* Converting the result to 1.15 format and saturate the output */
emilmont 1:fdd22bb7aa52 350 acc = __SSAT(acc, 16u);
emilmont 1:fdd22bb7aa52 351
emilmont 1:fdd22bb7aa52 352 /* Converting the result to 1.15 format */
emilmont 1:fdd22bb7aa52 353 //acc = __SSAT((acc >> (16u - shift)), 16u);
emilmont 1:fdd22bb7aa52 354
emilmont 1:fdd22bb7aa52 355 /* Store the result from accumulator into the destination buffer. */
emilmont 1:fdd22bb7aa52 356 *pOut++ = (q15_t) acc;
emilmont 1:fdd22bb7aa52 357
emilmont 1:fdd22bb7aa52 358 /* Compute and store error */
emilmont 1:fdd22bb7aa52 359 d = *pRef++;
emilmont 1:fdd22bb7aa52 360 e = d - (q15_t) acc;
emilmont 1:fdd22bb7aa52 361 *pErr++ = e;
emilmont 1:fdd22bb7aa52 362
emilmont 1:fdd22bb7aa52 363 /* Calculation of 1/energy */
emilmont 1:fdd22bb7aa52 364 postShift = arm_recip_q15((q15_t) energy + DELTA_Q15,
emilmont 1:fdd22bb7aa52 365 &oneByEnergy, S->recipTable);
emilmont 1:fdd22bb7aa52 366
emilmont 1:fdd22bb7aa52 367 /* Calculation of e * mu value */
emilmont 1:fdd22bb7aa52 368 errorXmu = (q15_t) (((q31_t) e * mu) >> 15);
emilmont 1:fdd22bb7aa52 369
emilmont 1:fdd22bb7aa52 370 /* Calculation of (e * mu) * (1/energy) value */
emilmont 1:fdd22bb7aa52 371 acc = (((q31_t) errorXmu * oneByEnergy) >> (15 - postShift));
emilmont 1:fdd22bb7aa52 372
emilmont 1:fdd22bb7aa52 373 /* Weighting factor for the normalized version */
emilmont 1:fdd22bb7aa52 374 w = (q15_t) __SSAT((q31_t) acc, 16);
emilmont 1:fdd22bb7aa52 375
emilmont 1:fdd22bb7aa52 376 /* Initialize pState pointer */
emilmont 1:fdd22bb7aa52 377 px = pState;
emilmont 1:fdd22bb7aa52 378
emilmont 1:fdd22bb7aa52 379 /* Initialize coeff pointer */
emilmont 1:fdd22bb7aa52 380 pb = (pCoeffs);
emilmont 1:fdd22bb7aa52 381
emilmont 1:fdd22bb7aa52 382 /* Loop over numTaps number of values */
emilmont 1:fdd22bb7aa52 383 tapCnt = numTaps;
emilmont 1:fdd22bb7aa52 384
emilmont 1:fdd22bb7aa52 385 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 386 {
emilmont 1:fdd22bb7aa52 387 /* Perform the multiply-accumulate */
emilmont 1:fdd22bb7aa52 388 coef = *pb + (((q31_t) w * (*px++)) >> 15);
emilmont 1:fdd22bb7aa52 389 *pb++ = (q15_t) __SSAT((coef), 16);
emilmont 1:fdd22bb7aa52 390
emilmont 1:fdd22bb7aa52 391 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 392 tapCnt--;
emilmont 1:fdd22bb7aa52 393 }
emilmont 1:fdd22bb7aa52 394
emilmont 1:fdd22bb7aa52 395 /* Read the sample from state buffer */
emilmont 1:fdd22bb7aa52 396 x0 = *pState;
emilmont 1:fdd22bb7aa52 397
emilmont 1:fdd22bb7aa52 398 /* Advance state pointer by 1 for the next sample */
emilmont 1:fdd22bb7aa52 399 pState = pState + 1u;
emilmont 1:fdd22bb7aa52 400
emilmont 1:fdd22bb7aa52 401 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 402 blkCnt--;
emilmont 1:fdd22bb7aa52 403 }
emilmont 1:fdd22bb7aa52 404
emilmont 1:fdd22bb7aa52 405 /* Save energy and x0 values for the next frame */
emilmont 1:fdd22bb7aa52 406 S->energy = (q15_t) energy;
emilmont 1:fdd22bb7aa52 407 S->x0 = x0;
emilmont 1:fdd22bb7aa52 408
emilmont 1:fdd22bb7aa52 409 /* Processing is complete. Now copy the last numTaps - 1 samples to the
emilmont 1:fdd22bb7aa52 410 satrt of the state buffer. This prepares the state buffer for the
emilmont 1:fdd22bb7aa52 411 next function call. */
emilmont 1:fdd22bb7aa52 412
emilmont 1:fdd22bb7aa52 413 /* Points to the start of the pState buffer */
emilmont 1:fdd22bb7aa52 414 pStateCurnt = S->pState;
emilmont 1:fdd22bb7aa52 415
emilmont 1:fdd22bb7aa52 416 /* copy (numTaps - 1u) data */
emilmont 1:fdd22bb7aa52 417 tapCnt = (numTaps - 1u);
emilmont 1:fdd22bb7aa52 418
emilmont 1:fdd22bb7aa52 419 /* copy data */
emilmont 1:fdd22bb7aa52 420 while(tapCnt > 0u)
emilmont 1:fdd22bb7aa52 421 {
emilmont 1:fdd22bb7aa52 422 *pStateCurnt++ = *pState++;
emilmont 1:fdd22bb7aa52 423
emilmont 1:fdd22bb7aa52 424 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 425 tapCnt--;
emilmont 1:fdd22bb7aa52 426 }
emilmont 1:fdd22bb7aa52 427
emilmont 1:fdd22bb7aa52 428 #endif /* #ifndef ARM_MATH_CM0 */
emilmont 1:fdd22bb7aa52 429
emilmont 1:fdd22bb7aa52 430 }
emilmont 1:fdd22bb7aa52 431
emilmont 1:fdd22bb7aa52 432
emilmont 1:fdd22bb7aa52 433 /**
emilmont 1:fdd22bb7aa52 434 * @} end of LMS_NORM group
emilmont 1:fdd22bb7aa52 435 */