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_interpolate_q15.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_interpolate_q15.c
emh203 0:3d9c67d97d6f 9 *
emh203 0:3d9c67d97d6f 10 * Description: Q15 FIR interpolation.
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 /**
emh203 0:3d9c67d97d6f 44 * @ingroup groupFilters
emh203 0:3d9c67d97d6f 45 */
emh203 0:3d9c67d97d6f 46
emh203 0:3d9c67d97d6f 47 /**
emh203 0:3d9c67d97d6f 48 * @addtogroup FIR_Interpolate
emh203 0:3d9c67d97d6f 49 * @{
emh203 0:3d9c67d97d6f 50 */
emh203 0:3d9c67d97d6f 51
emh203 0:3d9c67d97d6f 52 /**
emh203 0:3d9c67d97d6f 53 * @brief Processing function for the Q15 FIR interpolator.
emh203 0:3d9c67d97d6f 54 * @param[in] *S points to an instance of the Q15 FIR interpolator structure.
emh203 0:3d9c67d97d6f 55 * @param[in] *pSrc points to the block of input data.
emh203 0:3d9c67d97d6f 56 * @param[out] *pDst points to the block of output data.
emh203 0:3d9c67d97d6f 57 * @param[in] blockSize number of input samples to process per call.
emh203 0:3d9c67d97d6f 58 * @return none.
emh203 0:3d9c67d97d6f 59 *
emh203 0:3d9c67d97d6f 60 * <b>Scaling and Overflow Behavior:</b>
emh203 0:3d9c67d97d6f 61 * \par
emh203 0:3d9c67d97d6f 62 * The function is implemented using a 64-bit internal accumulator.
emh203 0:3d9c67d97d6f 63 * Both coefficients and state variables are represented in 1.15 format and multiplications yield a 2.30 result.
emh203 0:3d9c67d97d6f 64 * The 2.30 intermediate results are accumulated in a 64-bit accumulator in 34.30 format.
emh203 0:3d9c67d97d6f 65 * There is no risk of internal overflow with this approach and the full precision of intermediate multiplications is preserved.
emh203 0:3d9c67d97d6f 66 * After all additions have been performed, the accumulator is truncated to 34.15 format by discarding low 15 bits.
emh203 0:3d9c67d97d6f 67 * Lastly, the accumulator is saturated to yield a result in 1.15 format.
emh203 0:3d9c67d97d6f 68 */
emh203 0:3d9c67d97d6f 69
emh203 0:3d9c67d97d6f 70 #ifndef ARM_MATH_CM0_FAMILY
emh203 0:3d9c67d97d6f 71
emh203 0:3d9c67d97d6f 72 /* Run the below code for Cortex-M4 and Cortex-M3 */
emh203 0:3d9c67d97d6f 73
emh203 0:3d9c67d97d6f 74 void arm_fir_interpolate_q15(
emh203 0:3d9c67d97d6f 75 const arm_fir_interpolate_instance_q15 * S,
emh203 0:3d9c67d97d6f 76 q15_t * pSrc,
emh203 0:3d9c67d97d6f 77 q15_t * pDst,
emh203 0:3d9c67d97d6f 78 uint32_t blockSize)
emh203 0:3d9c67d97d6f 79 {
emh203 0:3d9c67d97d6f 80 q15_t *pState = S->pState; /* State pointer */
emh203 0:3d9c67d97d6f 81 q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
emh203 0:3d9c67d97d6f 82 q15_t *pStateCurnt; /* Points to the current sample of the state */
emh203 0:3d9c67d97d6f 83 q15_t *ptr1, *ptr2; /* Temporary pointers for state and coefficient buffers */
emh203 0:3d9c67d97d6f 84 q63_t sum0; /* Accumulators */
emh203 0:3d9c67d97d6f 85 q15_t x0, c0; /* Temporary variables to hold state and coefficient values */
emh203 0:3d9c67d97d6f 86 uint32_t i, blkCnt, j, tapCnt; /* Loop counters */
emh203 0:3d9c67d97d6f 87 uint16_t phaseLen = S->phaseLength; /* Length of each polyphase filter component */
emh203 0:3d9c67d97d6f 88 uint32_t blkCntN2;
emh203 0:3d9c67d97d6f 89 q63_t acc0, acc1;
emh203 0:3d9c67d97d6f 90 q15_t x1;
emh203 0:3d9c67d97d6f 91
emh203 0:3d9c67d97d6f 92 /* S->pState buffer contains previous frame (phaseLen - 1) samples */
emh203 0:3d9c67d97d6f 93 /* pStateCurnt points to the location where the new input data should be written */
emh203 0:3d9c67d97d6f 94 pStateCurnt = S->pState + ((q31_t) phaseLen - 1);
emh203 0:3d9c67d97d6f 95
emh203 0:3d9c67d97d6f 96 /* Initialise blkCnt */
emh203 0:3d9c67d97d6f 97 blkCnt = blockSize / 2;
emh203 0:3d9c67d97d6f 98 blkCntN2 = blockSize - (2 * blkCnt);
emh203 0:3d9c67d97d6f 99
emh203 0:3d9c67d97d6f 100 /* Samples loop unrolled by 2 */
emh203 0:3d9c67d97d6f 101 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 102 {
emh203 0:3d9c67d97d6f 103 /* Copy new input sample into the state buffer */
emh203 0:3d9c67d97d6f 104 *pStateCurnt++ = *pSrc++;
emh203 0:3d9c67d97d6f 105 *pStateCurnt++ = *pSrc++;
emh203 0:3d9c67d97d6f 106
emh203 0:3d9c67d97d6f 107 /* Address modifier index of coefficient buffer */
emh203 0:3d9c67d97d6f 108 j = 1u;
emh203 0:3d9c67d97d6f 109
emh203 0:3d9c67d97d6f 110 /* Loop over the Interpolation factor. */
emh203 0:3d9c67d97d6f 111 i = (S->L);
emh203 0:3d9c67d97d6f 112
emh203 0:3d9c67d97d6f 113 while(i > 0u)
emh203 0:3d9c67d97d6f 114 {
emh203 0:3d9c67d97d6f 115 /* Set accumulator to zero */
emh203 0:3d9c67d97d6f 116 acc0 = 0;
emh203 0:3d9c67d97d6f 117 acc1 = 0;
emh203 0:3d9c67d97d6f 118
emh203 0:3d9c67d97d6f 119 /* Initialize state pointer */
emh203 0:3d9c67d97d6f 120 ptr1 = pState;
emh203 0:3d9c67d97d6f 121
emh203 0:3d9c67d97d6f 122 /* Initialize coefficient pointer */
emh203 0:3d9c67d97d6f 123 ptr2 = pCoeffs + (S->L - j);
emh203 0:3d9c67d97d6f 124
emh203 0:3d9c67d97d6f 125 /* Loop over the polyPhase length. Unroll by a factor of 4.
emh203 0:3d9c67d97d6f 126 ** Repeat until we've computed numTaps-(4*S->L) coefficients. */
emh203 0:3d9c67d97d6f 127 tapCnt = phaseLen >> 2u;
emh203 0:3d9c67d97d6f 128
emh203 0:3d9c67d97d6f 129 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 130
emh203 0:3d9c67d97d6f 131 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 132 {
emh203 0:3d9c67d97d6f 133
emh203 0:3d9c67d97d6f 134 /* Read the input sample */
emh203 0:3d9c67d97d6f 135 x1 = *(ptr1++);
emh203 0:3d9c67d97d6f 136
emh203 0:3d9c67d97d6f 137 /* Read the coefficient */
emh203 0:3d9c67d97d6f 138 c0 = *(ptr2);
emh203 0:3d9c67d97d6f 139
emh203 0:3d9c67d97d6f 140 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 141 acc0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 142 acc1 += (q63_t) x1 *c0;
emh203 0:3d9c67d97d6f 143
emh203 0:3d9c67d97d6f 144
emh203 0:3d9c67d97d6f 145 /* Read the coefficient */
emh203 0:3d9c67d97d6f 146 c0 = *(ptr2 + S->L);
emh203 0:3d9c67d97d6f 147
emh203 0:3d9c67d97d6f 148 /* Read the input sample */
emh203 0:3d9c67d97d6f 149 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 150
emh203 0:3d9c67d97d6f 151 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 152 acc0 += (q63_t) x1 *c0;
emh203 0:3d9c67d97d6f 153 acc1 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 154
emh203 0:3d9c67d97d6f 155
emh203 0:3d9c67d97d6f 156 /* Read the coefficient */
emh203 0:3d9c67d97d6f 157 c0 = *(ptr2 + S->L * 2);
emh203 0:3d9c67d97d6f 158
emh203 0:3d9c67d97d6f 159 /* Read the input sample */
emh203 0:3d9c67d97d6f 160 x1 = *(ptr1++);
emh203 0:3d9c67d97d6f 161
emh203 0:3d9c67d97d6f 162 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 163 acc0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 164 acc1 += (q63_t) x1 *c0;
emh203 0:3d9c67d97d6f 165
emh203 0:3d9c67d97d6f 166 /* Read the coefficient */
emh203 0:3d9c67d97d6f 167 c0 = *(ptr2 + S->L * 3);
emh203 0:3d9c67d97d6f 168
emh203 0:3d9c67d97d6f 169 /* Read the input sample */
emh203 0:3d9c67d97d6f 170 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 171
emh203 0:3d9c67d97d6f 172 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 173 acc0 += (q63_t) x1 *c0;
emh203 0:3d9c67d97d6f 174 acc1 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 175
emh203 0:3d9c67d97d6f 176
emh203 0:3d9c67d97d6f 177 /* Upsampling is done by stuffing L-1 zeros between each sample.
emh203 0:3d9c67d97d6f 178 * So instead of multiplying zeros with coefficients,
emh203 0:3d9c67d97d6f 179 * Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 180 ptr2 += 4 * S->L;
emh203 0:3d9c67d97d6f 181
emh203 0:3d9c67d97d6f 182 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 183 tapCnt--;
emh203 0:3d9c67d97d6f 184 }
emh203 0:3d9c67d97d6f 185
emh203 0:3d9c67d97d6f 186 /* If the polyPhase length is not a multiple of 4, compute the remaining filter taps */
emh203 0:3d9c67d97d6f 187 tapCnt = phaseLen % 0x4u;
emh203 0:3d9c67d97d6f 188
emh203 0:3d9c67d97d6f 189 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 190 {
emh203 0:3d9c67d97d6f 191
emh203 0:3d9c67d97d6f 192 /* Read the input sample */
emh203 0:3d9c67d97d6f 193 x1 = *(ptr1++);
emh203 0:3d9c67d97d6f 194
emh203 0:3d9c67d97d6f 195 /* Read the coefficient */
emh203 0:3d9c67d97d6f 196 c0 = *(ptr2);
emh203 0:3d9c67d97d6f 197
emh203 0:3d9c67d97d6f 198 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 199 acc0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 200 acc1 += (q63_t) x1 *c0;
emh203 0:3d9c67d97d6f 201
emh203 0:3d9c67d97d6f 202 /* Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 203 ptr2 += S->L;
emh203 0:3d9c67d97d6f 204
emh203 0:3d9c67d97d6f 205 /* update states for next sample processing */
emh203 0:3d9c67d97d6f 206 x0 = x1;
emh203 0:3d9c67d97d6f 207
emh203 0:3d9c67d97d6f 208 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 209 tapCnt--;
emh203 0:3d9c67d97d6f 210 }
emh203 0:3d9c67d97d6f 211
emh203 0:3d9c67d97d6f 212 /* The result is in the accumulator, store in the destination buffer. */
emh203 0:3d9c67d97d6f 213 *pDst = (q15_t) (__SSAT((acc0 >> 15), 16));
emh203 0:3d9c67d97d6f 214 *(pDst + S->L) = (q15_t) (__SSAT((acc1 >> 15), 16));
emh203 0:3d9c67d97d6f 215
emh203 0:3d9c67d97d6f 216 pDst++;
emh203 0:3d9c67d97d6f 217
emh203 0:3d9c67d97d6f 218 /* Increment the address modifier index of coefficient buffer */
emh203 0:3d9c67d97d6f 219 j++;
emh203 0:3d9c67d97d6f 220
emh203 0:3d9c67d97d6f 221 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 222 i--;
emh203 0:3d9c67d97d6f 223 }
emh203 0:3d9c67d97d6f 224
emh203 0:3d9c67d97d6f 225 /* Advance the state pointer by 1
emh203 0:3d9c67d97d6f 226 * to process the next group of interpolation factor number samples */
emh203 0:3d9c67d97d6f 227 pState = pState + 2;
emh203 0:3d9c67d97d6f 228
emh203 0:3d9c67d97d6f 229 pDst += S->L;
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 /* If the blockSize is not a multiple of 2, compute any remaining output samples here.
emh203 0:3d9c67d97d6f 236 ** No loop unrolling is used. */
emh203 0:3d9c67d97d6f 237 blkCnt = blkCntN2;
emh203 0:3d9c67d97d6f 238
emh203 0:3d9c67d97d6f 239 /* Loop over the blockSize. */
emh203 0:3d9c67d97d6f 240 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 241 {
emh203 0:3d9c67d97d6f 242 /* Copy new input sample into the state buffer */
emh203 0:3d9c67d97d6f 243 *pStateCurnt++ = *pSrc++;
emh203 0:3d9c67d97d6f 244
emh203 0:3d9c67d97d6f 245 /* Address modifier index of coefficient buffer */
emh203 0:3d9c67d97d6f 246 j = 1u;
emh203 0:3d9c67d97d6f 247
emh203 0:3d9c67d97d6f 248 /* Loop over the Interpolation factor. */
emh203 0:3d9c67d97d6f 249 i = S->L;
emh203 0:3d9c67d97d6f 250 while(i > 0u)
emh203 0:3d9c67d97d6f 251 {
emh203 0:3d9c67d97d6f 252 /* Set accumulator to zero */
emh203 0:3d9c67d97d6f 253 sum0 = 0;
emh203 0:3d9c67d97d6f 254
emh203 0:3d9c67d97d6f 255 /* Initialize state pointer */
emh203 0:3d9c67d97d6f 256 ptr1 = pState;
emh203 0:3d9c67d97d6f 257
emh203 0:3d9c67d97d6f 258 /* Initialize coefficient pointer */
emh203 0:3d9c67d97d6f 259 ptr2 = pCoeffs + (S->L - j);
emh203 0:3d9c67d97d6f 260
emh203 0:3d9c67d97d6f 261 /* Loop over the polyPhase length. Unroll by a factor of 4.
emh203 0:3d9c67d97d6f 262 ** Repeat until we've computed numTaps-(4*S->L) coefficients. */
emh203 0:3d9c67d97d6f 263 tapCnt = phaseLen >> 2;
emh203 0:3d9c67d97d6f 264 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 265 {
emh203 0:3d9c67d97d6f 266
emh203 0:3d9c67d97d6f 267 /* Read the coefficient */
emh203 0:3d9c67d97d6f 268 c0 = *(ptr2);
emh203 0:3d9c67d97d6f 269
emh203 0:3d9c67d97d6f 270 /* Upsampling is done by stuffing L-1 zeros between each sample.
emh203 0:3d9c67d97d6f 271 * So instead of multiplying zeros with coefficients,
emh203 0:3d9c67d97d6f 272 * Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 273 ptr2 += S->L;
emh203 0:3d9c67d97d6f 274
emh203 0:3d9c67d97d6f 275 /* Read the input sample */
emh203 0:3d9c67d97d6f 276 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 277
emh203 0:3d9c67d97d6f 278 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 279 sum0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 280
emh203 0:3d9c67d97d6f 281 /* Read the coefficient */
emh203 0:3d9c67d97d6f 282 c0 = *(ptr2);
emh203 0:3d9c67d97d6f 283
emh203 0:3d9c67d97d6f 284 /* Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 285 ptr2 += S->L;
emh203 0:3d9c67d97d6f 286
emh203 0:3d9c67d97d6f 287 /* Read the input sample */
emh203 0:3d9c67d97d6f 288 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 289
emh203 0:3d9c67d97d6f 290 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 291 sum0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 292
emh203 0:3d9c67d97d6f 293 /* Read the coefficient */
emh203 0:3d9c67d97d6f 294 c0 = *(ptr2);
emh203 0:3d9c67d97d6f 295
emh203 0:3d9c67d97d6f 296 /* Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 297 ptr2 += S->L;
emh203 0:3d9c67d97d6f 298
emh203 0:3d9c67d97d6f 299 /* Read the input sample */
emh203 0:3d9c67d97d6f 300 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 301
emh203 0:3d9c67d97d6f 302 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 303 sum0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 304
emh203 0:3d9c67d97d6f 305 /* Read the coefficient */
emh203 0:3d9c67d97d6f 306 c0 = *(ptr2);
emh203 0:3d9c67d97d6f 307
emh203 0:3d9c67d97d6f 308 /* Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 309 ptr2 += S->L;
emh203 0:3d9c67d97d6f 310
emh203 0:3d9c67d97d6f 311 /* Read the input sample */
emh203 0:3d9c67d97d6f 312 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 313
emh203 0:3d9c67d97d6f 314 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 315 sum0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 316
emh203 0:3d9c67d97d6f 317 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 318 tapCnt--;
emh203 0:3d9c67d97d6f 319 }
emh203 0:3d9c67d97d6f 320
emh203 0:3d9c67d97d6f 321 /* If the polyPhase length is not a multiple of 4, compute the remaining filter taps */
emh203 0:3d9c67d97d6f 322 tapCnt = phaseLen & 0x3u;
emh203 0:3d9c67d97d6f 323
emh203 0:3d9c67d97d6f 324 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 325 {
emh203 0:3d9c67d97d6f 326 /* Read the coefficient */
emh203 0:3d9c67d97d6f 327 c0 = *(ptr2);
emh203 0:3d9c67d97d6f 328
emh203 0:3d9c67d97d6f 329 /* Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 330 ptr2 += S->L;
emh203 0:3d9c67d97d6f 331
emh203 0:3d9c67d97d6f 332 /* Read the input sample */
emh203 0:3d9c67d97d6f 333 x0 = *(ptr1++);
emh203 0:3d9c67d97d6f 334
emh203 0:3d9c67d97d6f 335 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 336 sum0 += (q63_t) x0 *c0;
emh203 0:3d9c67d97d6f 337
emh203 0:3d9c67d97d6f 338 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 339 tapCnt--;
emh203 0:3d9c67d97d6f 340 }
emh203 0:3d9c67d97d6f 341
emh203 0:3d9c67d97d6f 342 /* The result is in the accumulator, store in the destination buffer. */
emh203 0:3d9c67d97d6f 343 *pDst++ = (q15_t) (__SSAT((sum0 >> 15), 16));
emh203 0:3d9c67d97d6f 344
emh203 0:3d9c67d97d6f 345 j++;
emh203 0:3d9c67d97d6f 346
emh203 0:3d9c67d97d6f 347 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 348 i--;
emh203 0:3d9c67d97d6f 349 }
emh203 0:3d9c67d97d6f 350
emh203 0:3d9c67d97d6f 351 /* Advance the state pointer by 1
emh203 0:3d9c67d97d6f 352 * to process the next group of interpolation factor number samples */
emh203 0:3d9c67d97d6f 353 pState = pState + 1;
emh203 0:3d9c67d97d6f 354
emh203 0:3d9c67d97d6f 355 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 356 blkCnt--;
emh203 0:3d9c67d97d6f 357 }
emh203 0:3d9c67d97d6f 358
emh203 0:3d9c67d97d6f 359
emh203 0:3d9c67d97d6f 360 /* Processing is complete.
emh203 0:3d9c67d97d6f 361 ** Now copy the last phaseLen - 1 samples to the satrt of the state buffer.
emh203 0:3d9c67d97d6f 362 ** This prepares the state buffer for the next function call. */
emh203 0:3d9c67d97d6f 363
emh203 0:3d9c67d97d6f 364 /* Points to the start of the state buffer */
emh203 0:3d9c67d97d6f 365 pStateCurnt = S->pState;
emh203 0:3d9c67d97d6f 366
emh203 0:3d9c67d97d6f 367 i = ((uint32_t) phaseLen - 1u) >> 2u;
emh203 0:3d9c67d97d6f 368
emh203 0:3d9c67d97d6f 369 /* copy data */
emh203 0:3d9c67d97d6f 370 while(i > 0u)
emh203 0:3d9c67d97d6f 371 {
emh203 0:3d9c67d97d6f 372 #ifndef UNALIGNED_SUPPORT_DISABLE
emh203 0:3d9c67d97d6f 373
emh203 0:3d9c67d97d6f 374 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
emh203 0:3d9c67d97d6f 375 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
emh203 0:3d9c67d97d6f 376
emh203 0:3d9c67d97d6f 377 #else
emh203 0:3d9c67d97d6f 378
emh203 0:3d9c67d97d6f 379 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 380 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 381 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 382 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 383
emh203 0:3d9c67d97d6f 384 #endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */
emh203 0:3d9c67d97d6f 385
emh203 0:3d9c67d97d6f 386 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 387 i--;
emh203 0:3d9c67d97d6f 388 }
emh203 0:3d9c67d97d6f 389
emh203 0:3d9c67d97d6f 390 i = ((uint32_t) phaseLen - 1u) % 0x04u;
emh203 0:3d9c67d97d6f 391
emh203 0:3d9c67d97d6f 392 while(i > 0u)
emh203 0:3d9c67d97d6f 393 {
emh203 0:3d9c67d97d6f 394 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 395
emh203 0:3d9c67d97d6f 396 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 397 i--;
emh203 0:3d9c67d97d6f 398 }
emh203 0:3d9c67d97d6f 399 }
emh203 0:3d9c67d97d6f 400
emh203 0:3d9c67d97d6f 401 #else
emh203 0:3d9c67d97d6f 402
emh203 0:3d9c67d97d6f 403 /* Run the below code for Cortex-M0 */
emh203 0:3d9c67d97d6f 404
emh203 0:3d9c67d97d6f 405 void arm_fir_interpolate_q15(
emh203 0:3d9c67d97d6f 406 const arm_fir_interpolate_instance_q15 * S,
emh203 0:3d9c67d97d6f 407 q15_t * pSrc,
emh203 0:3d9c67d97d6f 408 q15_t * pDst,
emh203 0:3d9c67d97d6f 409 uint32_t blockSize)
emh203 0:3d9c67d97d6f 410 {
emh203 0:3d9c67d97d6f 411 q15_t *pState = S->pState; /* State pointer */
emh203 0:3d9c67d97d6f 412 q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
emh203 0:3d9c67d97d6f 413 q15_t *pStateCurnt; /* Points to the current sample of the state */
emh203 0:3d9c67d97d6f 414 q15_t *ptr1, *ptr2; /* Temporary pointers for state and coefficient buffers */
emh203 0:3d9c67d97d6f 415 q63_t sum; /* Accumulator */
emh203 0:3d9c67d97d6f 416 q15_t x0, c0; /* Temporary variables to hold state and coefficient values */
emh203 0:3d9c67d97d6f 417 uint32_t i, blkCnt, tapCnt; /* Loop counters */
emh203 0:3d9c67d97d6f 418 uint16_t phaseLen = S->phaseLength; /* Length of each polyphase filter component */
emh203 0:3d9c67d97d6f 419
emh203 0:3d9c67d97d6f 420
emh203 0:3d9c67d97d6f 421 /* S->pState buffer contains previous frame (phaseLen - 1) samples */
emh203 0:3d9c67d97d6f 422 /* pStateCurnt points to the location where the new input data should be written */
emh203 0:3d9c67d97d6f 423 pStateCurnt = S->pState + (phaseLen - 1u);
emh203 0:3d9c67d97d6f 424
emh203 0:3d9c67d97d6f 425 /* Total number of intput samples */
emh203 0:3d9c67d97d6f 426 blkCnt = blockSize;
emh203 0:3d9c67d97d6f 427
emh203 0:3d9c67d97d6f 428 /* Loop over the blockSize. */
emh203 0:3d9c67d97d6f 429 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 430 {
emh203 0:3d9c67d97d6f 431 /* Copy new input sample into the state buffer */
emh203 0:3d9c67d97d6f 432 *pStateCurnt++ = *pSrc++;
emh203 0:3d9c67d97d6f 433
emh203 0:3d9c67d97d6f 434 /* Loop over the Interpolation factor. */
emh203 0:3d9c67d97d6f 435 i = S->L;
emh203 0:3d9c67d97d6f 436
emh203 0:3d9c67d97d6f 437 while(i > 0u)
emh203 0:3d9c67d97d6f 438 {
emh203 0:3d9c67d97d6f 439 /* Set accumulator to zero */
emh203 0:3d9c67d97d6f 440 sum = 0;
emh203 0:3d9c67d97d6f 441
emh203 0:3d9c67d97d6f 442 /* Initialize state pointer */
emh203 0:3d9c67d97d6f 443 ptr1 = pState;
emh203 0:3d9c67d97d6f 444
emh203 0:3d9c67d97d6f 445 /* Initialize coefficient pointer */
emh203 0:3d9c67d97d6f 446 ptr2 = pCoeffs + (i - 1u);
emh203 0:3d9c67d97d6f 447
emh203 0:3d9c67d97d6f 448 /* Loop over the polyPhase length */
emh203 0:3d9c67d97d6f 449 tapCnt = (uint32_t) phaseLen;
emh203 0:3d9c67d97d6f 450
emh203 0:3d9c67d97d6f 451 while(tapCnt > 0u)
emh203 0:3d9c67d97d6f 452 {
emh203 0:3d9c67d97d6f 453 /* Read the coefficient */
emh203 0:3d9c67d97d6f 454 c0 = *ptr2;
emh203 0:3d9c67d97d6f 455
emh203 0:3d9c67d97d6f 456 /* Increment the coefficient pointer by interpolation factor times. */
emh203 0:3d9c67d97d6f 457 ptr2 += S->L;
emh203 0:3d9c67d97d6f 458
emh203 0:3d9c67d97d6f 459 /* Read the input sample */
emh203 0:3d9c67d97d6f 460 x0 = *ptr1++;
emh203 0:3d9c67d97d6f 461
emh203 0:3d9c67d97d6f 462 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 463 sum += ((q31_t) x0 * c0);
emh203 0:3d9c67d97d6f 464
emh203 0:3d9c67d97d6f 465 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 466 tapCnt--;
emh203 0:3d9c67d97d6f 467 }
emh203 0:3d9c67d97d6f 468
emh203 0:3d9c67d97d6f 469 /* Store the result after converting to 1.15 format in the destination buffer */
emh203 0:3d9c67d97d6f 470 *pDst++ = (q15_t) (__SSAT((sum >> 15), 16));
emh203 0:3d9c67d97d6f 471
emh203 0:3d9c67d97d6f 472 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 473 i--;
emh203 0:3d9c67d97d6f 474 }
emh203 0:3d9c67d97d6f 475
emh203 0:3d9c67d97d6f 476 /* Advance the state pointer by 1
emh203 0:3d9c67d97d6f 477 * to process the next group of interpolation factor number samples */
emh203 0:3d9c67d97d6f 478 pState = pState + 1;
emh203 0:3d9c67d97d6f 479
emh203 0:3d9c67d97d6f 480 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 481 blkCnt--;
emh203 0:3d9c67d97d6f 482 }
emh203 0:3d9c67d97d6f 483
emh203 0:3d9c67d97d6f 484 /* Processing is complete.
emh203 0:3d9c67d97d6f 485 ** Now copy the last phaseLen - 1 samples to the start of the state buffer.
emh203 0:3d9c67d97d6f 486 ** This prepares the state buffer for the next function call. */
emh203 0:3d9c67d97d6f 487
emh203 0:3d9c67d97d6f 488 /* Points to the start of the state buffer */
emh203 0:3d9c67d97d6f 489 pStateCurnt = S->pState;
emh203 0:3d9c67d97d6f 490
emh203 0:3d9c67d97d6f 491 i = (uint32_t) phaseLen - 1u;
emh203 0:3d9c67d97d6f 492
emh203 0:3d9c67d97d6f 493 while(i > 0u)
emh203 0:3d9c67d97d6f 494 {
emh203 0:3d9c67d97d6f 495 *pStateCurnt++ = *pState++;
emh203 0:3d9c67d97d6f 496
emh203 0:3d9c67d97d6f 497 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 498 i--;
emh203 0:3d9c67d97d6f 499 }
emh203 0:3d9c67d97d6f 500
emh203 0:3d9c67d97d6f 501 }
emh203 0:3d9c67d97d6f 502
emh203 0:3d9c67d97d6f 503 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
emh203 0:3d9c67d97d6f 504
emh203 0:3d9c67d97d6f 505
emh203 0:3d9c67d97d6f 506 /**
emh203 0:3d9c67d97d6f 507 * @} end of FIR_Interpolate group
emh203 0:3d9c67d97d6f 508 */