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_fir_sparse_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_fir_sparse_q31.c
emh203 0:3d9c67d97d6f 9 *
emh203 0:3d9c67d97d6f 10 * Description: Q31 sparse FIR filter processing function.
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 #include "arm_math.h"
emh203 0:3d9c67d97d6f 41
emh203 0:3d9c67d97d6f 42
emh203 0:3d9c67d97d6f 43 /**
emh203 0:3d9c67d97d6f 44 * @addtogroup FIR_Sparse
emh203 0:3d9c67d97d6f 45 * @{
emh203 0:3d9c67d97d6f 46 */
emh203 0:3d9c67d97d6f 47
emh203 0:3d9c67d97d6f 48 /**
emh203 0:3d9c67d97d6f 49 * @brief Processing function for the Q31 sparse FIR filter.
emh203 0:3d9c67d97d6f 50 * @param[in] *S points to an instance of the Q31 sparse FIR structure.
emh203 0:3d9c67d97d6f 51 * @param[in] *pSrc points to the block of input data.
emh203 0:3d9c67d97d6f 52 * @param[out] *pDst points to the block of output data
emh203 0:3d9c67d97d6f 53 * @param[in] *pScratchIn points to a temporary buffer of size blockSize.
emh203 0:3d9c67d97d6f 54 * @param[in] blockSize number of input samples to process per call.
emh203 0:3d9c67d97d6f 55 * @return none.
emh203 0:3d9c67d97d6f 56 *
emh203 0:3d9c67d97d6f 57 * <b>Scaling and Overflow Behavior:</b>
emh203 0:3d9c67d97d6f 58 * \par
emh203 0:3d9c67d97d6f 59 * The function is implemented using an internal 32-bit accumulator.
emh203 0:3d9c67d97d6f 60 * The 1.31 x 1.31 multiplications are truncated to 2.30 format.
emh203 0:3d9c67d97d6f 61 * This leads to loss of precision on the intermediate multiplications and provides only a single guard bit.
emh203 0:3d9c67d97d6f 62 * If the accumulator result overflows, it wraps around rather than saturate.
emh203 0:3d9c67d97d6f 63 * In order to avoid overflows the input signal or coefficients must be scaled down by log2(numTaps) bits.
emh203 0:3d9c67d97d6f 64 */
emh203 0:3d9c67d97d6f 65
emh203 0:3d9c67d97d6f 66 void arm_fir_sparse_q31(
emh203 0:3d9c67d97d6f 67 arm_fir_sparse_instance_q31 * S,
emh203 0:3d9c67d97d6f 68 q31_t * pSrc,
emh203 0:3d9c67d97d6f 69 q31_t * pDst,
emh203 0:3d9c67d97d6f 70 q31_t * pScratchIn,
emh203 0:3d9c67d97d6f 71 uint32_t blockSize)
emh203 0:3d9c67d97d6f 72 {
emh203 0:3d9c67d97d6f 73
emh203 0:3d9c67d97d6f 74 q31_t *pState = S->pState; /* State pointer */
emh203 0:3d9c67d97d6f 75 q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
emh203 0:3d9c67d97d6f 76 q31_t *px; /* Scratch buffer pointer */
emh203 0:3d9c67d97d6f 77 q31_t *py = pState; /* Temporary pointers for state buffer */
emh203 0:3d9c67d97d6f 78 q31_t *pb = pScratchIn; /* Temporary pointers for scratch buffer */
emh203 0:3d9c67d97d6f 79 q31_t *pOut; /* Destination pointer */
emh203 0:3d9c67d97d6f 80 q63_t out; /* Temporary output variable */
emh203 0:3d9c67d97d6f 81 int32_t *pTapDelay = S->pTapDelay; /* Pointer to the array containing offset of the non-zero tap values. */
emh203 0:3d9c67d97d6f 82 uint32_t delaySize = S->maxDelay + blockSize; /* state length */
emh203 0:3d9c67d97d6f 83 uint16_t numTaps = S->numTaps; /* Filter order */
emh203 0:3d9c67d97d6f 84 int32_t readIndex; /* Read index of the state buffer */
emh203 0:3d9c67d97d6f 85 uint32_t tapCnt, blkCnt; /* loop counters */
emh203 0:3d9c67d97d6f 86 q31_t coeff = *pCoeffs++; /* Read the first coefficient value */
emh203 0:3d9c67d97d6f 87 q31_t in;
emh203 0:3d9c67d97d6f 88
emh203 0:3d9c67d97d6f 89
emh203 0:3d9c67d97d6f 90 /* BlockSize of Input samples are copied into the state buffer */
emh203 0:3d9c67d97d6f 91 /* StateIndex points to the starting position to write in the state buffer */
emh203 0:3d9c67d97d6f 92 arm_circularWrite_f32((int32_t *) py, delaySize, &S->stateIndex, 1,
emh203 0:3d9c67d97d6f 93 (int32_t *) pSrc, 1, blockSize);
emh203 0:3d9c67d97d6f 94
emh203 0:3d9c67d97d6f 95 /* Read Index, from where the state buffer should be read, is calculated. */
emh203 0:3d9c67d97d6f 96 readIndex = (int32_t) (S->stateIndex - blockSize) - *pTapDelay++;
emh203 0:3d9c67d97d6f 97
emh203 0:3d9c67d97d6f 98 /* Wraparound of readIndex */
emh203 0:3d9c67d97d6f 99 if(readIndex < 0)
emh203 0:3d9c67d97d6f 100 {
emh203 0:3d9c67d97d6f 101 readIndex += (int32_t) delaySize;
emh203 0:3d9c67d97d6f 102 }
emh203 0:3d9c67d97d6f 103
emh203 0:3d9c67d97d6f 104 /* Working pointer for state buffer is updated */
emh203 0:3d9c67d97d6f 105 py = pState;
emh203 0:3d9c67d97d6f 106
emh203 0:3d9c67d97d6f 107 /* blockSize samples are read from the state buffer */
emh203 0:3d9c67d97d6f 108 arm_circularRead_f32((int32_t *) py, delaySize, &readIndex, 1,
emh203 0:3d9c67d97d6f 109 (int32_t *) pb, (int32_t *) pb, blockSize, 1,
emh203 0:3d9c67d97d6f 110 blockSize);
emh203 0:3d9c67d97d6f 111
emh203 0:3d9c67d97d6f 112 /* Working pointer for the scratch buffer of state values */
emh203 0:3d9c67d97d6f 113 px = pb;
emh203 0:3d9c67d97d6f 114
emh203 0:3d9c67d97d6f 115 /* Working pointer for scratch buffer of output values */
emh203 0:3d9c67d97d6f 116 pOut = pDst;
emh203 0:3d9c67d97d6f 117
emh203 0:3d9c67d97d6f 118
emh203 0:3d9c67d97d6f 119 #ifndef ARM_MATH_CM0_FAMILY
emh203 0:3d9c67d97d6f 120
emh203 0:3d9c67d97d6f 121 /* Run the below code for Cortex-M4 and Cortex-M3 */
emh203 0:3d9c67d97d6f 122
emh203 0:3d9c67d97d6f 123 /* Loop over the blockSize. Unroll by a factor of 4.
emh203 0:3d9c67d97d6f 124 * Compute 4 Multiplications at a time. */
emh203 0:3d9c67d97d6f 125 blkCnt = blockSize >> 2;
emh203 0:3d9c67d97d6f 126
emh203 0:3d9c67d97d6f 127 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 128 {
emh203 0:3d9c67d97d6f 129 /* Perform Multiplications and store in the destination buffer */
emh203 0:3d9c67d97d6f 130 *pOut++ = (q31_t) (((q63_t) * px++ * coeff) >> 32);
emh203 0:3d9c67d97d6f 131 *pOut++ = (q31_t) (((q63_t) * px++ * coeff) >> 32);
emh203 0:3d9c67d97d6f 132 *pOut++ = (q31_t) (((q63_t) * px++ * coeff) >> 32);
emh203 0:3d9c67d97d6f 133 *pOut++ = (q31_t) (((q63_t) * px++ * coeff) >> 32);
emh203 0:3d9c67d97d6f 134
emh203 0:3d9c67d97d6f 135 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 136 blkCnt--;
emh203 0:3d9c67d97d6f 137 }
emh203 0:3d9c67d97d6f 138
emh203 0:3d9c67d97d6f 139 /* If the blockSize is not a multiple of 4,
emh203 0:3d9c67d97d6f 140 * compute the remaining samples */
emh203 0:3d9c67d97d6f 141 blkCnt = blockSize % 0x4u;
emh203 0:3d9c67d97d6f 142
emh203 0:3d9c67d97d6f 143 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 144 {
emh203 0:3d9c67d97d6f 145 /* Perform Multiplications and store in the destination buffer */
emh203 0:3d9c67d97d6f 146 *pOut++ = (q31_t) (((q63_t) * px++ * coeff) >> 32);
emh203 0:3d9c67d97d6f 147
emh203 0:3d9c67d97d6f 148 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 149 blkCnt--;
emh203 0:3d9c67d97d6f 150 }
emh203 0:3d9c67d97d6f 151
emh203 0:3d9c67d97d6f 152 /* Load the coefficient value and
emh203 0:3d9c67d97d6f 153 * increment the coefficient buffer for the next set of state values */
emh203 0:3d9c67d97d6f 154 coeff = *pCoeffs++;
emh203 0:3d9c67d97d6f 155
emh203 0:3d9c67d97d6f 156 /* Read Index, from where the state buffer should be read, is calculated. */
emh203 0:3d9c67d97d6f 157 readIndex = (int32_t) (S->stateIndex - blockSize) - *pTapDelay++;
emh203 0:3d9c67d97d6f 158
emh203 0:3d9c67d97d6f 159 /* Wraparound of readIndex */
emh203 0:3d9c67d97d6f 160 if(readIndex < 0)
emh203 0:3d9c67d97d6f 161 {
emh203 0:3d9c67d97d6f 162 readIndex += (int32_t) delaySize;
emh203 0:3d9c67d97d6f 163 }
emh203 0:3d9c67d97d6f 164
emh203 0:3d9c67d97d6f 165 /* Loop over the number of taps. */
emh203 0:3d9c67d97d6f 166 tapCnt = (uint32_t) numTaps - 1u;
emh203 0:3d9c67d97d6f 167
emh203 0:3d9c67d97d6f 168 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 169 {
emh203 0:3d9c67d97d6f 170 /* Working pointer for state buffer is updated */
emh203 0:3d9c67d97d6f 171 py = pState;
emh203 0:3d9c67d97d6f 172
emh203 0:3d9c67d97d6f 173 /* blockSize samples are read from the state buffer */
emh203 0:3d9c67d97d6f 174 arm_circularRead_f32((int32_t *) py, delaySize, &readIndex, 1,
emh203 0:3d9c67d97d6f 175 (int32_t *) pb, (int32_t *) pb, blockSize, 1,
emh203 0:3d9c67d97d6f 176 blockSize);
emh203 0:3d9c67d97d6f 177
emh203 0:3d9c67d97d6f 178 /* Working pointer for the scratch buffer of state values */
emh203 0:3d9c67d97d6f 179 px = pb;
emh203 0:3d9c67d97d6f 180
emh203 0:3d9c67d97d6f 181 /* Working pointer for scratch buffer of output values */
emh203 0:3d9c67d97d6f 182 pOut = pDst;
emh203 0:3d9c67d97d6f 183
emh203 0:3d9c67d97d6f 184 /* Loop over the blockSize. Unroll by a factor of 4.
emh203 0:3d9c67d97d6f 185 * Compute 4 MACS at a time. */
emh203 0:3d9c67d97d6f 186 blkCnt = blockSize >> 2;
emh203 0:3d9c67d97d6f 187
emh203 0:3d9c67d97d6f 188 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 189 {
emh203 0:3d9c67d97d6f 190 out = *pOut;
emh203 0:3d9c67d97d6f 191 out += ((q63_t) * px++ * coeff) >> 32;
emh203 0:3d9c67d97d6f 192 *pOut++ = (q31_t) (out);
emh203 0:3d9c67d97d6f 193
emh203 0:3d9c67d97d6f 194 out = *pOut;
emh203 0:3d9c67d97d6f 195 out += ((q63_t) * px++ * coeff) >> 32;
emh203 0:3d9c67d97d6f 196 *pOut++ = (q31_t) (out);
emh203 0:3d9c67d97d6f 197
emh203 0:3d9c67d97d6f 198 out = *pOut;
emh203 0:3d9c67d97d6f 199 out += ((q63_t) * px++ * coeff) >> 32;
emh203 0:3d9c67d97d6f 200 *pOut++ = (q31_t) (out);
emh203 0:3d9c67d97d6f 201
emh203 0:3d9c67d97d6f 202 out = *pOut;
emh203 0:3d9c67d97d6f 203 out += ((q63_t) * px++ * coeff) >> 32;
emh203 0:3d9c67d97d6f 204 *pOut++ = (q31_t) (out);
emh203 0:3d9c67d97d6f 205
emh203 0:3d9c67d97d6f 206 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 207 blkCnt--;
emh203 0:3d9c67d97d6f 208 }
emh203 0:3d9c67d97d6f 209
emh203 0:3d9c67d97d6f 210 /* If the blockSize is not a multiple of 4,
emh203 0:3d9c67d97d6f 211 * compute the remaining samples */
emh203 0:3d9c67d97d6f 212 blkCnt = blockSize % 0x4u;
emh203 0:3d9c67d97d6f 213
emh203 0:3d9c67d97d6f 214 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 215 {
emh203 0:3d9c67d97d6f 216 /* Perform Multiply-Accumulate */
emh203 0:3d9c67d97d6f 217 out = *pOut;
emh203 0:3d9c67d97d6f 218 out += ((q63_t) * px++ * coeff) >> 32;
emh203 0:3d9c67d97d6f 219 *pOut++ = (q31_t) (out);
emh203 0:3d9c67d97d6f 220
emh203 0:3d9c67d97d6f 221 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 222 blkCnt--;
emh203 0:3d9c67d97d6f 223 }
emh203 0:3d9c67d97d6f 224
emh203 0:3d9c67d97d6f 225 /* Load the coefficient value and
emh203 0:3d9c67d97d6f 226 * increment the coefficient buffer for the next set of state values */
emh203 0:3d9c67d97d6f 227 coeff = *pCoeffs++;
emh203 0:3d9c67d97d6f 228
emh203 0:3d9c67d97d6f 229 /* Read Index, from where the state buffer should be read, is calculated. */
emh203 0:3d9c67d97d6f 230 readIndex = (int32_t) (S->stateIndex - blockSize) - *pTapDelay++;
emh203 0:3d9c67d97d6f 231
emh203 0:3d9c67d97d6f 232 /* Wraparound of readIndex */
emh203 0:3d9c67d97d6f 233 if(readIndex < 0)
emh203 0:3d9c67d97d6f 234 {
emh203 0:3d9c67d97d6f 235 readIndex += (int32_t) delaySize;
emh203 0:3d9c67d97d6f 236 }
emh203 0:3d9c67d97d6f 237
emh203 0:3d9c67d97d6f 238 /* Decrement the tap loop counter */
emh203 0:3d9c67d97d6f 239 tapCnt--;
emh203 0:3d9c67d97d6f 240 }
emh203 0:3d9c67d97d6f 241
emh203 0:3d9c67d97d6f 242 /* Working output pointer is updated */
emh203 0:3d9c67d97d6f 243 pOut = pDst;
emh203 0:3d9c67d97d6f 244
emh203 0:3d9c67d97d6f 245 /* Output is converted into 1.31 format. */
emh203 0:3d9c67d97d6f 246 /* Loop over the blockSize. Unroll by a factor of 4.
emh203 0:3d9c67d97d6f 247 * process 4 output samples at a time. */
emh203 0:3d9c67d97d6f 248 blkCnt = blockSize >> 2;
emh203 0:3d9c67d97d6f 249
emh203 0:3d9c67d97d6f 250 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 251 {
emh203 0:3d9c67d97d6f 252 in = *pOut << 1;
emh203 0:3d9c67d97d6f 253 *pOut++ = in;
emh203 0:3d9c67d97d6f 254 in = *pOut << 1;
emh203 0:3d9c67d97d6f 255 *pOut++ = in;
emh203 0:3d9c67d97d6f 256 in = *pOut << 1;
emh203 0:3d9c67d97d6f 257 *pOut++ = in;
emh203 0:3d9c67d97d6f 258 in = *pOut << 1;
emh203 0:3d9c67d97d6f 259 *pOut++ = in;
emh203 0:3d9c67d97d6f 260
emh203 0:3d9c67d97d6f 261 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 262 blkCnt--;
emh203 0:3d9c67d97d6f 263 }
emh203 0:3d9c67d97d6f 264
emh203 0:3d9c67d97d6f 265 /* If the blockSize is not a multiple of 4,
emh203 0:3d9c67d97d6f 266 * process the remaining output samples */
emh203 0:3d9c67d97d6f 267 blkCnt = blockSize % 0x4u;
emh203 0:3d9c67d97d6f 268
emh203 0:3d9c67d97d6f 269 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 270 {
emh203 0:3d9c67d97d6f 271 in = *pOut << 1;
emh203 0:3d9c67d97d6f 272 *pOut++ = in;
emh203 0:3d9c67d97d6f 273
emh203 0:3d9c67d97d6f 274 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 275 blkCnt--;
emh203 0:3d9c67d97d6f 276 }
emh203 0:3d9c67d97d6f 277
emh203 0:3d9c67d97d6f 278 #else
emh203 0:3d9c67d97d6f 279
emh203 0:3d9c67d97d6f 280 /* Run the below code for Cortex-M0 */
emh203 0:3d9c67d97d6f 281 blkCnt = blockSize;
emh203 0:3d9c67d97d6f 282
emh203 0:3d9c67d97d6f 283 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 284 {
emh203 0:3d9c67d97d6f 285 /* Perform Multiplications and store in the destination buffer */
emh203 0:3d9c67d97d6f 286 *pOut++ = (q31_t) (((q63_t) * px++ * coeff) >> 32);
emh203 0:3d9c67d97d6f 287
emh203 0:3d9c67d97d6f 288 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 289 blkCnt--;
emh203 0:3d9c67d97d6f 290 }
emh203 0:3d9c67d97d6f 291
emh203 0:3d9c67d97d6f 292 /* Load the coefficient value and
emh203 0:3d9c67d97d6f 293 * increment the coefficient buffer for the next set of state values */
emh203 0:3d9c67d97d6f 294 coeff = *pCoeffs++;
emh203 0:3d9c67d97d6f 295
emh203 0:3d9c67d97d6f 296 /* Read Index, from where the state buffer should be read, is calculated. */
emh203 0:3d9c67d97d6f 297 readIndex = (int32_t) (S->stateIndex - blockSize) - *pTapDelay++;
emh203 0:3d9c67d97d6f 298
emh203 0:3d9c67d97d6f 299 /* Wraparound of readIndex */
emh203 0:3d9c67d97d6f 300 if(readIndex < 0)
emh203 0:3d9c67d97d6f 301 {
emh203 0:3d9c67d97d6f 302 readIndex += (int32_t) delaySize;
emh203 0:3d9c67d97d6f 303 }
emh203 0:3d9c67d97d6f 304
emh203 0:3d9c67d97d6f 305 /* Loop over the number of taps. */
emh203 0:3d9c67d97d6f 306 tapCnt = (uint32_t) numTaps - 1u;
emh203 0:3d9c67d97d6f 307
emh203 0:3d9c67d97d6f 308 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 309 {
emh203 0:3d9c67d97d6f 310 /* Working pointer for state buffer is updated */
emh203 0:3d9c67d97d6f 311 py = pState;
emh203 0:3d9c67d97d6f 312
emh203 0:3d9c67d97d6f 313 /* blockSize samples are read from the state buffer */
emh203 0:3d9c67d97d6f 314 arm_circularRead_f32((int32_t *) py, delaySize, &readIndex, 1,
emh203 0:3d9c67d97d6f 315 (int32_t *) pb, (int32_t *) pb, blockSize, 1,
emh203 0:3d9c67d97d6f 316 blockSize);
emh203 0:3d9c67d97d6f 317
emh203 0:3d9c67d97d6f 318 /* Working pointer for the scratch buffer of state values */
emh203 0:3d9c67d97d6f 319 px = pb;
emh203 0:3d9c67d97d6f 320
emh203 0:3d9c67d97d6f 321 /* Working pointer for scratch buffer of output values */
emh203 0:3d9c67d97d6f 322 pOut = pDst;
emh203 0:3d9c67d97d6f 323
emh203 0:3d9c67d97d6f 324 blkCnt = blockSize;
emh203 0:3d9c67d97d6f 325
emh203 0:3d9c67d97d6f 326 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 327 {
emh203 0:3d9c67d97d6f 328 /* Perform Multiply-Accumulate */
emh203 0:3d9c67d97d6f 329 out = *pOut;
emh203 0:3d9c67d97d6f 330 out += ((q63_t) * px++ * coeff) >> 32;
emh203 0:3d9c67d97d6f 331 *pOut++ = (q31_t) (out);
emh203 0:3d9c67d97d6f 332
emh203 0:3d9c67d97d6f 333 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 334 blkCnt--;
emh203 0:3d9c67d97d6f 335 }
emh203 0:3d9c67d97d6f 336
emh203 0:3d9c67d97d6f 337 /* Load the coefficient value and
emh203 0:3d9c67d97d6f 338 * increment the coefficient buffer for the next set of state values */
emh203 0:3d9c67d97d6f 339 coeff = *pCoeffs++;
emh203 0:3d9c67d97d6f 340
emh203 0:3d9c67d97d6f 341 /* Read Index, from where the state buffer should be read, is calculated. */
emh203 0:3d9c67d97d6f 342 readIndex = (int32_t) (S->stateIndex - blockSize) - *pTapDelay++;
emh203 0:3d9c67d97d6f 343
emh203 0:3d9c67d97d6f 344 /* Wraparound of readIndex */
emh203 0:3d9c67d97d6f 345 if(readIndex < 0)
emh203 0:3d9c67d97d6f 346 {
emh203 0:3d9c67d97d6f 347 readIndex += (int32_t) delaySize;
emh203 0:3d9c67d97d6f 348 }
emh203 0:3d9c67d97d6f 349
emh203 0:3d9c67d97d6f 350 /* Decrement the tap loop counter */
emh203 0:3d9c67d97d6f 351 tapCnt--;
emh203 0:3d9c67d97d6f 352 }
emh203 0:3d9c67d97d6f 353
emh203 0:3d9c67d97d6f 354 /* Working output pointer is updated */
emh203 0:3d9c67d97d6f 355 pOut = pDst;
emh203 0:3d9c67d97d6f 356
emh203 0:3d9c67d97d6f 357 /* Output is converted into 1.31 format. */
emh203 0:3d9c67d97d6f 358 blkCnt = blockSize;
emh203 0:3d9c67d97d6f 359
emh203 0:3d9c67d97d6f 360 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 361 {
emh203 0:3d9c67d97d6f 362 in = *pOut << 1;
emh203 0:3d9c67d97d6f 363 *pOut++ = in;
emh203 0:3d9c67d97d6f 364
emh203 0:3d9c67d97d6f 365 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 366 blkCnt--;
emh203 0:3d9c67d97d6f 367 }
emh203 0:3d9c67d97d6f 368
emh203 0:3d9c67d97d6f 369 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
emh203 0:3d9c67d97d6f 370
emh203 0:3d9c67d97d6f 371 }
emh203 0:3d9c67d97d6f 372
emh203 0:3d9c67d97d6f 373 /**
emh203 0:3d9c67d97d6f 374 * @} end of FIR_Sparse group
emh203 0:3d9c67d97d6f 375 */