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functions/FilteringFunctions/arm_fir_decimate_q31.c@3:4098b9d3d571, 2018-06-21 (annotated)
- Committer:
- xorjoep
- Date:
- Thu Jun 21 11:56:27 2018 +0000
- Revision:
- 3:4098b9d3d571
- Parent:
- 1:24714b45cd1b
headers is a folder not a library
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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xorjoep | 1:24714b45cd1b | 1 | /* ---------------------------------------------------------------------- |
xorjoep | 1:24714b45cd1b | 2 | * Project: CMSIS DSP Library |
xorjoep | 1:24714b45cd1b | 3 | * Title: arm_fir_decimate_q31.c |
xorjoep | 1:24714b45cd1b | 4 | * Description: Q31 FIR Decimator |
xorjoep | 1:24714b45cd1b | 5 | * |
xorjoep | 1:24714b45cd1b | 6 | * $Date: 27. January 2017 |
xorjoep | 1:24714b45cd1b | 7 | * $Revision: V.1.5.1 |
xorjoep | 1:24714b45cd1b | 8 | * |
xorjoep | 1:24714b45cd1b | 9 | * Target Processor: Cortex-M cores |
xorjoep | 1:24714b45cd1b | 10 | * -------------------------------------------------------------------- */ |
xorjoep | 1:24714b45cd1b | 11 | /* |
xorjoep | 1:24714b45cd1b | 12 | * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved. |
xorjoep | 1:24714b45cd1b | 13 | * |
xorjoep | 1:24714b45cd1b | 14 | * SPDX-License-Identifier: Apache-2.0 |
xorjoep | 1:24714b45cd1b | 15 | * |
xorjoep | 1:24714b45cd1b | 16 | * Licensed under the Apache License, Version 2.0 (the License); you may |
xorjoep | 1:24714b45cd1b | 17 | * not use this file except in compliance with the License. |
xorjoep | 1:24714b45cd1b | 18 | * You may obtain a copy of the License at |
xorjoep | 1:24714b45cd1b | 19 | * |
xorjoep | 1:24714b45cd1b | 20 | * www.apache.org/licenses/LICENSE-2.0 |
xorjoep | 1:24714b45cd1b | 21 | * |
xorjoep | 1:24714b45cd1b | 22 | * Unless required by applicable law or agreed to in writing, software |
xorjoep | 1:24714b45cd1b | 23 | * distributed under the License is distributed on an AS IS BASIS, WITHOUT |
xorjoep | 1:24714b45cd1b | 24 | * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
xorjoep | 1:24714b45cd1b | 25 | * See the License for the specific language governing permissions and |
xorjoep | 1:24714b45cd1b | 26 | * limitations under the License. |
xorjoep | 1:24714b45cd1b | 27 | */ |
xorjoep | 1:24714b45cd1b | 28 | |
xorjoep | 1:24714b45cd1b | 29 | #include "arm_math.h" |
xorjoep | 1:24714b45cd1b | 30 | |
xorjoep | 1:24714b45cd1b | 31 | /** |
xorjoep | 1:24714b45cd1b | 32 | * @ingroup groupFilters |
xorjoep | 1:24714b45cd1b | 33 | */ |
xorjoep | 1:24714b45cd1b | 34 | |
xorjoep | 1:24714b45cd1b | 35 | /** |
xorjoep | 1:24714b45cd1b | 36 | * @addtogroup FIR_decimate |
xorjoep | 1:24714b45cd1b | 37 | * @{ |
xorjoep | 1:24714b45cd1b | 38 | */ |
xorjoep | 1:24714b45cd1b | 39 | |
xorjoep | 1:24714b45cd1b | 40 | /** |
xorjoep | 1:24714b45cd1b | 41 | * @brief Processing function for the Q31 FIR decimator. |
xorjoep | 1:24714b45cd1b | 42 | * @param[in] *S points to an instance of the Q31 FIR decimator structure. |
xorjoep | 1:24714b45cd1b | 43 | * @param[in] *pSrc points to the block of input data. |
xorjoep | 1:24714b45cd1b | 44 | * @param[out] *pDst points to the block of output data |
xorjoep | 1:24714b45cd1b | 45 | * @param[in] blockSize number of input samples to process per call. |
xorjoep | 1:24714b45cd1b | 46 | * @return none |
xorjoep | 1:24714b45cd1b | 47 | * |
xorjoep | 1:24714b45cd1b | 48 | * <b>Scaling and Overflow Behavior:</b> |
xorjoep | 1:24714b45cd1b | 49 | * \par |
xorjoep | 1:24714b45cd1b | 50 | * The function is implemented using an internal 64-bit accumulator. |
xorjoep | 1:24714b45cd1b | 51 | * The accumulator has a 2.62 format and maintains full precision of the intermediate multiplication results but provides only a single guard bit. |
xorjoep | 1:24714b45cd1b | 52 | * Thus, if the accumulator result overflows it wraps around rather than clip. |
xorjoep | 1:24714b45cd1b | 53 | * In order to avoid overflows completely the input signal must be scaled down by log2(numTaps) bits (where log2 is read as log to the base 2). |
xorjoep | 1:24714b45cd1b | 54 | * After all multiply-accumulates are performed, the 2.62 accumulator is truncated to 1.32 format and then saturated to 1.31 format. |
xorjoep | 1:24714b45cd1b | 55 | * |
xorjoep | 1:24714b45cd1b | 56 | * \par |
xorjoep | 1:24714b45cd1b | 57 | * Refer to the function <code>arm_fir_decimate_fast_q31()</code> for a faster but less precise implementation of this function for Cortex-M3 and Cortex-M4. |
xorjoep | 1:24714b45cd1b | 58 | */ |
xorjoep | 1:24714b45cd1b | 59 | |
xorjoep | 1:24714b45cd1b | 60 | void arm_fir_decimate_q31( |
xorjoep | 1:24714b45cd1b | 61 | const arm_fir_decimate_instance_q31 * S, |
xorjoep | 1:24714b45cd1b | 62 | q31_t * pSrc, |
xorjoep | 1:24714b45cd1b | 63 | q31_t * pDst, |
xorjoep | 1:24714b45cd1b | 64 | uint32_t blockSize) |
xorjoep | 1:24714b45cd1b | 65 | { |
xorjoep | 1:24714b45cd1b | 66 | q31_t *pState = S->pState; /* State pointer */ |
xorjoep | 1:24714b45cd1b | 67 | q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */ |
xorjoep | 1:24714b45cd1b | 68 | q31_t *pStateCurnt; /* Points to the current sample of the state */ |
xorjoep | 1:24714b45cd1b | 69 | q31_t x0, c0; /* Temporary variables to hold state and coefficient values */ |
xorjoep | 1:24714b45cd1b | 70 | q31_t *px; /* Temporary pointers for state buffer */ |
xorjoep | 1:24714b45cd1b | 71 | q31_t *pb; /* Temporary pointers for coefficient buffer */ |
xorjoep | 1:24714b45cd1b | 72 | q63_t sum0; /* Accumulator */ |
xorjoep | 1:24714b45cd1b | 73 | uint32_t numTaps = S->numTaps; /* Number of taps */ |
xorjoep | 1:24714b45cd1b | 74 | uint32_t i, tapCnt, blkCnt, outBlockSize = blockSize / S->M; /* Loop counters */ |
xorjoep | 1:24714b45cd1b | 75 | |
xorjoep | 1:24714b45cd1b | 76 | |
xorjoep | 1:24714b45cd1b | 77 | #if defined (ARM_MATH_DSP) |
xorjoep | 1:24714b45cd1b | 78 | |
xorjoep | 1:24714b45cd1b | 79 | /* Run the below code for Cortex-M4 and Cortex-M3 */ |
xorjoep | 1:24714b45cd1b | 80 | |
xorjoep | 1:24714b45cd1b | 81 | /* S->pState buffer contains previous frame (numTaps - 1) samples */ |
xorjoep | 1:24714b45cd1b | 82 | /* pStateCurnt points to the location where the new input data should be written */ |
xorjoep | 1:24714b45cd1b | 83 | pStateCurnt = S->pState + (numTaps - 1U); |
xorjoep | 1:24714b45cd1b | 84 | |
xorjoep | 1:24714b45cd1b | 85 | /* Total number of output samples to be computed */ |
xorjoep | 1:24714b45cd1b | 86 | blkCnt = outBlockSize; |
xorjoep | 1:24714b45cd1b | 87 | |
xorjoep | 1:24714b45cd1b | 88 | while (blkCnt > 0U) |
xorjoep | 1:24714b45cd1b | 89 | { |
xorjoep | 1:24714b45cd1b | 90 | /* Copy decimation factor number of new input samples into the state buffer */ |
xorjoep | 1:24714b45cd1b | 91 | i = S->M; |
xorjoep | 1:24714b45cd1b | 92 | |
xorjoep | 1:24714b45cd1b | 93 | do |
xorjoep | 1:24714b45cd1b | 94 | { |
xorjoep | 1:24714b45cd1b | 95 | *pStateCurnt++ = *pSrc++; |
xorjoep | 1:24714b45cd1b | 96 | |
xorjoep | 1:24714b45cd1b | 97 | } while (--i); |
xorjoep | 1:24714b45cd1b | 98 | |
xorjoep | 1:24714b45cd1b | 99 | /* Set accumulator to zero */ |
xorjoep | 1:24714b45cd1b | 100 | sum0 = 0; |
xorjoep | 1:24714b45cd1b | 101 | |
xorjoep | 1:24714b45cd1b | 102 | /* Initialize state pointer */ |
xorjoep | 1:24714b45cd1b | 103 | px = pState; |
xorjoep | 1:24714b45cd1b | 104 | |
xorjoep | 1:24714b45cd1b | 105 | /* Initialize coeff pointer */ |
xorjoep | 1:24714b45cd1b | 106 | pb = pCoeffs; |
xorjoep | 1:24714b45cd1b | 107 | |
xorjoep | 1:24714b45cd1b | 108 | /* Loop unrolling. Process 4 taps at a time. */ |
xorjoep | 1:24714b45cd1b | 109 | tapCnt = numTaps >> 2; |
xorjoep | 1:24714b45cd1b | 110 | |
xorjoep | 1:24714b45cd1b | 111 | /* Loop over the number of taps. Unroll by a factor of 4. |
xorjoep | 1:24714b45cd1b | 112 | ** Repeat until we've computed numTaps-4 coefficients. */ |
xorjoep | 1:24714b45cd1b | 113 | while (tapCnt > 0U) |
xorjoep | 1:24714b45cd1b | 114 | { |
xorjoep | 1:24714b45cd1b | 115 | /* Read the b[numTaps-1] coefficient */ |
xorjoep | 1:24714b45cd1b | 116 | c0 = *(pb++); |
xorjoep | 1:24714b45cd1b | 117 | |
xorjoep | 1:24714b45cd1b | 118 | /* Read x[n-numTaps-1] sample */ |
xorjoep | 1:24714b45cd1b | 119 | x0 = *(px++); |
xorjoep | 1:24714b45cd1b | 120 | |
xorjoep | 1:24714b45cd1b | 121 | /* Perform the multiply-accumulate */ |
xorjoep | 1:24714b45cd1b | 122 | sum0 += (q63_t) x0 *c0; |
xorjoep | 1:24714b45cd1b | 123 | |
xorjoep | 1:24714b45cd1b | 124 | /* Read the b[numTaps-2] coefficient */ |
xorjoep | 1:24714b45cd1b | 125 | c0 = *(pb++); |
xorjoep | 1:24714b45cd1b | 126 | |
xorjoep | 1:24714b45cd1b | 127 | /* Read x[n-numTaps-2] sample */ |
xorjoep | 1:24714b45cd1b | 128 | x0 = *(px++); |
xorjoep | 1:24714b45cd1b | 129 | |
xorjoep | 1:24714b45cd1b | 130 | /* Perform the multiply-accumulate */ |
xorjoep | 1:24714b45cd1b | 131 | sum0 += (q63_t) x0 *c0; |
xorjoep | 1:24714b45cd1b | 132 | |
xorjoep | 1:24714b45cd1b | 133 | /* Read the b[numTaps-3] coefficient */ |
xorjoep | 1:24714b45cd1b | 134 | c0 = *(pb++); |
xorjoep | 1:24714b45cd1b | 135 | |
xorjoep | 1:24714b45cd1b | 136 | /* Read x[n-numTaps-3] sample */ |
xorjoep | 1:24714b45cd1b | 137 | x0 = *(px++); |
xorjoep | 1:24714b45cd1b | 138 | |
xorjoep | 1:24714b45cd1b | 139 | /* Perform the multiply-accumulate */ |
xorjoep | 1:24714b45cd1b | 140 | sum0 += (q63_t) x0 *c0; |
xorjoep | 1:24714b45cd1b | 141 | |
xorjoep | 1:24714b45cd1b | 142 | /* Read the b[numTaps-4] coefficient */ |
xorjoep | 1:24714b45cd1b | 143 | c0 = *(pb++); |
xorjoep | 1:24714b45cd1b | 144 | |
xorjoep | 1:24714b45cd1b | 145 | /* Read x[n-numTaps-4] sample */ |
xorjoep | 1:24714b45cd1b | 146 | x0 = *(px++); |
xorjoep | 1:24714b45cd1b | 147 | |
xorjoep | 1:24714b45cd1b | 148 | /* Perform the multiply-accumulate */ |
xorjoep | 1:24714b45cd1b | 149 | sum0 += (q63_t) x0 *c0; |
xorjoep | 1:24714b45cd1b | 150 | |
xorjoep | 1:24714b45cd1b | 151 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 152 | tapCnt--; |
xorjoep | 1:24714b45cd1b | 153 | } |
xorjoep | 1:24714b45cd1b | 154 | |
xorjoep | 1:24714b45cd1b | 155 | /* If the filter length is not a multiple of 4, compute the remaining filter taps */ |
xorjoep | 1:24714b45cd1b | 156 | tapCnt = numTaps % 0x4U; |
xorjoep | 1:24714b45cd1b | 157 | |
xorjoep | 1:24714b45cd1b | 158 | while (tapCnt > 0U) |
xorjoep | 1:24714b45cd1b | 159 | { |
xorjoep | 1:24714b45cd1b | 160 | /* Read coefficients */ |
xorjoep | 1:24714b45cd1b | 161 | c0 = *(pb++); |
xorjoep | 1:24714b45cd1b | 162 | |
xorjoep | 1:24714b45cd1b | 163 | /* Fetch 1 state variable */ |
xorjoep | 1:24714b45cd1b | 164 | x0 = *(px++); |
xorjoep | 1:24714b45cd1b | 165 | |
xorjoep | 1:24714b45cd1b | 166 | /* Perform the multiply-accumulate */ |
xorjoep | 1:24714b45cd1b | 167 | sum0 += (q63_t) x0 *c0; |
xorjoep | 1:24714b45cd1b | 168 | |
xorjoep | 1:24714b45cd1b | 169 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 170 | tapCnt--; |
xorjoep | 1:24714b45cd1b | 171 | } |
xorjoep | 1:24714b45cd1b | 172 | |
xorjoep | 1:24714b45cd1b | 173 | /* Advance the state pointer by the decimation factor |
xorjoep | 1:24714b45cd1b | 174 | * to process the next group of decimation factor number samples */ |
xorjoep | 1:24714b45cd1b | 175 | pState = pState + S->M; |
xorjoep | 1:24714b45cd1b | 176 | |
xorjoep | 1:24714b45cd1b | 177 | /* The result is in the accumulator, store in the destination buffer. */ |
xorjoep | 1:24714b45cd1b | 178 | *pDst++ = (q31_t) (sum0 >> 31); |
xorjoep | 1:24714b45cd1b | 179 | |
xorjoep | 1:24714b45cd1b | 180 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 181 | blkCnt--; |
xorjoep | 1:24714b45cd1b | 182 | } |
xorjoep | 1:24714b45cd1b | 183 | |
xorjoep | 1:24714b45cd1b | 184 | /* Processing is complete. |
xorjoep | 1:24714b45cd1b | 185 | ** Now copy the last numTaps - 1 samples to the satrt of the state buffer. |
xorjoep | 1:24714b45cd1b | 186 | ** This prepares the state buffer for the next function call. */ |
xorjoep | 1:24714b45cd1b | 187 | |
xorjoep | 1:24714b45cd1b | 188 | /* Points to the start of the state buffer */ |
xorjoep | 1:24714b45cd1b | 189 | pStateCurnt = S->pState; |
xorjoep | 1:24714b45cd1b | 190 | |
xorjoep | 1:24714b45cd1b | 191 | i = (numTaps - 1U) >> 2U; |
xorjoep | 1:24714b45cd1b | 192 | |
xorjoep | 1:24714b45cd1b | 193 | /* copy data */ |
xorjoep | 1:24714b45cd1b | 194 | while (i > 0U) |
xorjoep | 1:24714b45cd1b | 195 | { |
xorjoep | 1:24714b45cd1b | 196 | *pStateCurnt++ = *pState++; |
xorjoep | 1:24714b45cd1b | 197 | *pStateCurnt++ = *pState++; |
xorjoep | 1:24714b45cd1b | 198 | *pStateCurnt++ = *pState++; |
xorjoep | 1:24714b45cd1b | 199 | *pStateCurnt++ = *pState++; |
xorjoep | 1:24714b45cd1b | 200 | |
xorjoep | 1:24714b45cd1b | 201 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 202 | i--; |
xorjoep | 1:24714b45cd1b | 203 | } |
xorjoep | 1:24714b45cd1b | 204 | |
xorjoep | 1:24714b45cd1b | 205 | i = (numTaps - 1U) % 0x04U; |
xorjoep | 1:24714b45cd1b | 206 | |
xorjoep | 1:24714b45cd1b | 207 | /* copy data */ |
xorjoep | 1:24714b45cd1b | 208 | while (i > 0U) |
xorjoep | 1:24714b45cd1b | 209 | { |
xorjoep | 1:24714b45cd1b | 210 | *pStateCurnt++ = *pState++; |
xorjoep | 1:24714b45cd1b | 211 | |
xorjoep | 1:24714b45cd1b | 212 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 213 | i--; |
xorjoep | 1:24714b45cd1b | 214 | } |
xorjoep | 1:24714b45cd1b | 215 | |
xorjoep | 1:24714b45cd1b | 216 | #else |
xorjoep | 1:24714b45cd1b | 217 | |
xorjoep | 1:24714b45cd1b | 218 | /* Run the below code for Cortex-M0 */ |
xorjoep | 1:24714b45cd1b | 219 | |
xorjoep | 1:24714b45cd1b | 220 | /* S->pState buffer contains previous frame (numTaps - 1) samples */ |
xorjoep | 1:24714b45cd1b | 221 | /* pStateCurnt points to the location where the new input data should be written */ |
xorjoep | 1:24714b45cd1b | 222 | pStateCurnt = S->pState + (numTaps - 1U); |
xorjoep | 1:24714b45cd1b | 223 | |
xorjoep | 1:24714b45cd1b | 224 | /* Total number of output samples to be computed */ |
xorjoep | 1:24714b45cd1b | 225 | blkCnt = outBlockSize; |
xorjoep | 1:24714b45cd1b | 226 | |
xorjoep | 1:24714b45cd1b | 227 | while (blkCnt > 0U) |
xorjoep | 1:24714b45cd1b | 228 | { |
xorjoep | 1:24714b45cd1b | 229 | /* Copy decimation factor number of new input samples into the state buffer */ |
xorjoep | 1:24714b45cd1b | 230 | i = S->M; |
xorjoep | 1:24714b45cd1b | 231 | |
xorjoep | 1:24714b45cd1b | 232 | do |
xorjoep | 1:24714b45cd1b | 233 | { |
xorjoep | 1:24714b45cd1b | 234 | *pStateCurnt++ = *pSrc++; |
xorjoep | 1:24714b45cd1b | 235 | |
xorjoep | 1:24714b45cd1b | 236 | } while (--i); |
xorjoep | 1:24714b45cd1b | 237 | |
xorjoep | 1:24714b45cd1b | 238 | /* Set accumulator to zero */ |
xorjoep | 1:24714b45cd1b | 239 | sum0 = 0; |
xorjoep | 1:24714b45cd1b | 240 | |
xorjoep | 1:24714b45cd1b | 241 | /* Initialize state pointer */ |
xorjoep | 1:24714b45cd1b | 242 | px = pState; |
xorjoep | 1:24714b45cd1b | 243 | |
xorjoep | 1:24714b45cd1b | 244 | /* Initialize coeff pointer */ |
xorjoep | 1:24714b45cd1b | 245 | pb = pCoeffs; |
xorjoep | 1:24714b45cd1b | 246 | |
xorjoep | 1:24714b45cd1b | 247 | tapCnt = numTaps; |
xorjoep | 1:24714b45cd1b | 248 | |
xorjoep | 1:24714b45cd1b | 249 | while (tapCnt > 0U) |
xorjoep | 1:24714b45cd1b | 250 | { |
xorjoep | 1:24714b45cd1b | 251 | /* Read coefficients */ |
xorjoep | 1:24714b45cd1b | 252 | c0 = *pb++; |
xorjoep | 1:24714b45cd1b | 253 | |
xorjoep | 1:24714b45cd1b | 254 | /* Fetch 1 state variable */ |
xorjoep | 1:24714b45cd1b | 255 | x0 = *px++; |
xorjoep | 1:24714b45cd1b | 256 | |
xorjoep | 1:24714b45cd1b | 257 | /* Perform the multiply-accumulate */ |
xorjoep | 1:24714b45cd1b | 258 | sum0 += (q63_t) x0 *c0; |
xorjoep | 1:24714b45cd1b | 259 | |
xorjoep | 1:24714b45cd1b | 260 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 261 | tapCnt--; |
xorjoep | 1:24714b45cd1b | 262 | } |
xorjoep | 1:24714b45cd1b | 263 | |
xorjoep | 1:24714b45cd1b | 264 | /* Advance the state pointer by the decimation factor |
xorjoep | 1:24714b45cd1b | 265 | * to process the next group of decimation factor number samples */ |
xorjoep | 1:24714b45cd1b | 266 | pState = pState + S->M; |
xorjoep | 1:24714b45cd1b | 267 | |
xorjoep | 1:24714b45cd1b | 268 | /* The result is in the accumulator, store in the destination buffer. */ |
xorjoep | 1:24714b45cd1b | 269 | *pDst++ = (q31_t) (sum0 >> 31); |
xorjoep | 1:24714b45cd1b | 270 | |
xorjoep | 1:24714b45cd1b | 271 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 272 | blkCnt--; |
xorjoep | 1:24714b45cd1b | 273 | } |
xorjoep | 1:24714b45cd1b | 274 | |
xorjoep | 1:24714b45cd1b | 275 | /* Processing is complete. |
xorjoep | 1:24714b45cd1b | 276 | ** Now copy the last numTaps - 1 samples to the start of the state buffer. |
xorjoep | 1:24714b45cd1b | 277 | ** This prepares the state buffer for the next function call. */ |
xorjoep | 1:24714b45cd1b | 278 | |
xorjoep | 1:24714b45cd1b | 279 | /* Points to the start of the state buffer */ |
xorjoep | 1:24714b45cd1b | 280 | pStateCurnt = S->pState; |
xorjoep | 1:24714b45cd1b | 281 | |
xorjoep | 1:24714b45cd1b | 282 | i = numTaps - 1U; |
xorjoep | 1:24714b45cd1b | 283 | |
xorjoep | 1:24714b45cd1b | 284 | /* copy data */ |
xorjoep | 1:24714b45cd1b | 285 | while (i > 0U) |
xorjoep | 1:24714b45cd1b | 286 | { |
xorjoep | 1:24714b45cd1b | 287 | *pStateCurnt++ = *pState++; |
xorjoep | 1:24714b45cd1b | 288 | |
xorjoep | 1:24714b45cd1b | 289 | /* Decrement the loop counter */ |
xorjoep | 1:24714b45cd1b | 290 | i--; |
xorjoep | 1:24714b45cd1b | 291 | } |
xorjoep | 1:24714b45cd1b | 292 | |
xorjoep | 1:24714b45cd1b | 293 | #endif /* #if defined (ARM_MATH_DSP) */ |
xorjoep | 1:24714b45cd1b | 294 | |
xorjoep | 1:24714b45cd1b | 295 | } |
xorjoep | 1:24714b45cd1b | 296 | |
xorjoep | 1:24714b45cd1b | 297 | /** |
xorjoep | 1:24714b45cd1b | 298 | * @} end of FIR_decimate group |
xorjoep | 1:24714b45cd1b | 299 | */ |