ST / X_NUCLEO_CCA02M1

Library to handle the X-NUCLEO-CCA02M1 MEMS Microphones Expansion Board.

Dependencies:   ST_I2S ST_FREQUENCY_DIVIDER USBDEVICE

Dependents:   HelloWorld_CCA02M1 HelloWorld_CCA02M1_mbedOS HelloWorld_CCA02M1 Karaoke_CCA01M1_CCA02M1_mbedOS

Fork of X_NUCLEO_CCA02M1 by ST Expansion SW Team

MEMS Microphones Library

Library to handle the X-NUCLEO-CCA02M1 MEMS Microphones Expansion Board. A single board allows to record a standard 2-channel stereo signal as an array of PCM samples (16 bit/sample); in principle, it could make use of six additional MEMS microphones to realize a 8-channel audio system.


Microphones configuration

Currently the configurations supported are the following:

  • Stereo@48KHz
  • Stereo@44.1KHz (CD audio quality)
  • Stereo@32KHz
  • Stereo@16KHz
  • Stereo@8KHz
  • Mono@48KHz
  • Mono@44.1KHz
  • Mono@32KHz
  • Mono@16KHz
  • Mono@8KHz

Mono configurations need a Jumper connecting PB_5 and PB_13 on the Morpho connector to properly work.


Platform compatibility

  • This board can be currently used with the Nucleo F4 Family only, please see the ST_I2S library compatibility for further information.
  • The library is compatible both with mbed OS 5.x and mbed classic 2.x (to work with mbed classic, the main application has to import the "events" library, which is not included into the "mbed" library).


I2S Peripheral Usage

By default this board makes use of the I2S peripheral available on Nucleo boards.


Acquiring through the USB

In order to acquire the recorded PCM audio channel with an audio SW on a PC, please connect the expansion board to a USB port of the PC, and the Nucleo board to a USB power supply.

Middlewares/OpenPDM2PCM/OpenPDMFilter.c@20:9952bef19da1, 2017-05-05 (annotated)

Committer:
Davidroid
Date:
Fri May 05 11:34:10 2017 +0000
Revision:
20:9952bef19da1
Parent:
16:4ab2eac7be21
Child:
25:f2c04f757003
Simplifying code.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
davide.aliprandi@st.com 2:9f389fd8fb2e 1 /**
davide.aliprandi@st.com 2:9f389fd8fb2e 2 ******************************************************************************
Davidroid 20:9952bef19da1 3 * @file OpenPDMFilter.c
davide.aliprandi@st.com 2:9f389fd8fb2e 4 * @author CL
davide.aliprandi@st.com 2:9f389fd8fb2e 5 * @version V1.0.0
davide.aliprandi@st.com 2:9f389fd8fb2e 6 * @date 9-September-2015
davide.aliprandi@st.com 2:9f389fd8fb2e 7 * @brief Open PDM audio software decoding Library.
davide.aliprandi@st.com 2:9f389fd8fb2e 8 * This Library is used to decode and reconstruct the audio signal
davide.aliprandi@st.com 2:9f389fd8fb2e 9 * produced by ST MEMS microphone (MP45Dxxx, MP34Dxxx).
davide.aliprandi@st.com 2:9f389fd8fb2e 10 ******************************************************************************
davide.aliprandi@st.com 2:9f389fd8fb2e 11 * @attention
davide.aliprandi@st.com 2:9f389fd8fb2e 12 *
davide.aliprandi@st.com 2:9f389fd8fb2e 13 * <h2><center>&copy; COPYRIGHT 2013 STMicroelectronics</center></h2>
davide.aliprandi@st.com 2:9f389fd8fb2e 14 *
davide.aliprandi@st.com 2:9f389fd8fb2e 15 * Licensed under MCD-ST Image SW License Agreement V2, (the "License");
davide.aliprandi@st.com 2:9f389fd8fb2e 16 * You may not use this file except in compliance with the License.
davide.aliprandi@st.com 2:9f389fd8fb2e 17 * You may obtain a copy of the License at:
davide.aliprandi@st.com 2:9f389fd8fb2e 18 *
davide.aliprandi@st.com 2:9f389fd8fb2e 19 * http://www.st.com/software_license_agreement_image_v2
davide.aliprandi@st.com 2:9f389fd8fb2e 20 *
davide.aliprandi@st.com 2:9f389fd8fb2e 21 * Unless required by applicable law or agreed to in writing, software
davide.aliprandi@st.com 2:9f389fd8fb2e 22 * distributed under the License is distributed on an "AS IS" BASIS,
davide.aliprandi@st.com 2:9f389fd8fb2e 23 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
davide.aliprandi@st.com 2:9f389fd8fb2e 24 * See the License for the specific language governing permissions and
davide.aliprandi@st.com 2:9f389fd8fb2e 25 * limitations under the License.
davide.aliprandi@st.com 2:9f389fd8fb2e 26 *
davide.aliprandi@st.com 2:9f389fd8fb2e 27 ******************************************************************************
davide.aliprandi@st.com 2:9f389fd8fb2e 28 */
davide.aliprandi@st.com 2:9f389fd8fb2e 29
davide.aliprandi@st.com 2:9f389fd8fb2e 30
davide.aliprandi@st.com 2:9f389fd8fb2e 31 /* Includes ------------------------------------------------------------------*/
davide.aliprandi@st.com 2:9f389fd8fb2e 32
davide.aliprandi@st.com 2:9f389fd8fb2e 33 #include "OpenPDMFilter.h"
davide.aliprandi@st.com 2:9f389fd8fb2e 34
davide.aliprandi@st.com 2:9f389fd8fb2e 35
davide.aliprandi@st.com 2:9f389fd8fb2e 36 /* Variables -----------------------------------------------------------------*/
davide.aliprandi@st.com 2:9f389fd8fb2e 37
davide.aliprandi@st.com 16:4ab2eac7be21 38 uint32_t div_const = 0;
davide.aliprandi@st.com 16:4ab2eac7be21 39 int64_t sub_const = 0;
Davidroid 20:9952bef19da1 40 uint32_t sinc[DECIMATION_MAX * SINCN];
davide.aliprandi@st.com 15:17bdadc6aa9c 41 uint32_t sinc1[DECIMATION_MAX];
davide.aliprandi@st.com 16:4ab2eac7be21 42 uint32_t sinc2[DECIMATION_MAX * 2];
Davidroid 20:9952bef19da1 43 uint32_t coef[SINCN][DECIMATION_MAX];
davide.aliprandi@st.com 15:17bdadc6aa9c 44 #ifdef USE_LUT
Davidroid 20:9952bef19da1 45 int32_t lut[256][DECIMATION_MAX / 8][SINCN];
davide.aliprandi@st.com 15:17bdadc6aa9c 46 #endif
davide.aliprandi@st.com 2:9f389fd8fb2e 47
davide.aliprandi@st.com 2:9f389fd8fb2e 48
davide.aliprandi@st.com 2:9f389fd8fb2e 49 /* Functions -----------------------------------------------------------------*/
davide.aliprandi@st.com 2:9f389fd8fb2e 50
davide.aliprandi@st.com 15:17bdadc6aa9c 51 #ifdef USE_LUT
Davidroid 20:9952bef19da1 52 int32_t filter_table_mono_64(uint8_t *data, uint8_t sincn)
davide.aliprandi@st.com 16:4ab2eac7be21 53 {
davide.aliprandi@st.com 16:4ab2eac7be21 54 return (int32_t)
davide.aliprandi@st.com 16:4ab2eac7be21 55 lut[data[0]][0][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 56 lut[data[1]][1][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 57 lut[data[2]][2][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 58 lut[data[3]][3][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 59 lut[data[4]][4][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 60 lut[data[5]][5][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 61 lut[data[6]][6][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 62 lut[data[7]][7][sincn];
davide.aliprandi@st.com 16:4ab2eac7be21 63 }
Davidroid 20:9952bef19da1 64 int32_t filter_table_stereo_64(uint8_t *data, uint8_t sincn)
davide.aliprandi@st.com 15:17bdadc6aa9c 65 {
davide.aliprandi@st.com 16:4ab2eac7be21 66 return (int32_t)
davide.aliprandi@st.com 16:4ab2eac7be21 67 lut[data[0]][0][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 68 lut[data[2]][1][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 69 lut[data[4]][2][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 70 lut[data[6]][3][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 71 lut[data[8]][4][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 72 lut[data[10]][5][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 73 lut[data[12]][6][sincn] +
davide.aliprandi@st.com 16:4ab2eac7be21 74 lut[data[14]][7][sincn];
davide.aliprandi@st.com 15:17bdadc6aa9c 75 }
Davidroid 20:9952bef19da1 76 int32_t filter_table_mono_128(uint8_t *data, uint8_t sincn)
Davidroid 20:9952bef19da1 77 {
Davidroid 20:9952bef19da1 78 return (int32_t)
Davidroid 20:9952bef19da1 79 lut[data[0]][0][sincn] +
Davidroid 20:9952bef19da1 80 lut[data[1]][1][sincn] +
Davidroid 20:9952bef19da1 81 lut[data[2]][2][sincn] +
Davidroid 20:9952bef19da1 82 lut[data[3]][3][sincn] +
Davidroid 20:9952bef19da1 83 lut[data[4]][4][sincn] +
Davidroid 20:9952bef19da1 84 lut[data[5]][5][sincn] +
Davidroid 20:9952bef19da1 85 lut[data[6]][6][sincn] +
Davidroid 20:9952bef19da1 86 lut[data[7]][7][sincn] +
Davidroid 20:9952bef19da1 87 lut[data[8]][8][sincn] +
Davidroid 20:9952bef19da1 88 lut[data[9]][9][sincn] +
Davidroid 20:9952bef19da1 89 lut[data[10]][10][sincn] +
Davidroid 20:9952bef19da1 90 lut[data[11]][11][sincn] +
Davidroid 20:9952bef19da1 91 lut[data[12]][12][sincn] +
Davidroid 20:9952bef19da1 92 lut[data[13]][13][sincn] +
Davidroid 20:9952bef19da1 93 lut[data[14]][14][sincn] +
Davidroid 20:9952bef19da1 94 lut[data[15]][15][sincn];
Davidroid 20:9952bef19da1 95 }
Davidroid 20:9952bef19da1 96 int32_t filter_table_stereo_128(uint8_t *data, uint8_t sincn)
Davidroid 20:9952bef19da1 97 {
Davidroid 20:9952bef19da1 98 return (int32_t)
Davidroid 20:9952bef19da1 99 lut[data[0]][0][sincn] +
Davidroid 20:9952bef19da1 100 lut[data[2]][1][sincn] +
Davidroid 20:9952bef19da1 101 lut[data[4]][2][sincn] +
Davidroid 20:9952bef19da1 102 lut[data[6]][3][sincn] +
Davidroid 20:9952bef19da1 103 lut[data[8]][4][sincn] +
Davidroid 20:9952bef19da1 104 lut[data[10]][5][sincn] +
Davidroid 20:9952bef19da1 105 lut[data[12]][6][sincn] +
Davidroid 20:9952bef19da1 106 lut[data[14]][7][sincn] +
Davidroid 20:9952bef19da1 107 lut[data[16]][8][sincn] +
Davidroid 20:9952bef19da1 108 lut[data[18]][9][sincn] +
Davidroid 20:9952bef19da1 109 lut[data[20]][10][sincn] +
Davidroid 20:9952bef19da1 110 lut[data[22]][11][sincn] +
Davidroid 20:9952bef19da1 111 lut[data[24]][12][sincn] +
Davidroid 20:9952bef19da1 112 lut[data[26]][13][sincn] +
Davidroid 20:9952bef19da1 113 lut[data[28]][14][sincn] +
Davidroid 20:9952bef19da1 114 lut[data[30]][15][sincn];
Davidroid 20:9952bef19da1 115 }
Davidroid 20:9952bef19da1 116 int32_t (* filter_tables_64[2]) (uint8_t *data, uint8_t sincn) = {filter_table_mono_64, filter_table_stereo_64};
Davidroid 20:9952bef19da1 117 int32_t (* filter_tables_128[2]) (uint8_t *data, uint8_t sincn) = {filter_table_mono_128, filter_table_stereo_128};
davide.aliprandi@st.com 15:17bdadc6aa9c 118 #else
Davidroid 20:9952bef19da1 119 int32_t filter_table(uint8_t *data, uint8_t sincn, TPDMFilter_InitStruct *param)
davide.aliprandi@st.com 2:9f389fd8fb2e 120 {
Davidroid 13:90465220b75f 121 uint8_t c, i;
davide.aliprandi@st.com 11:b2f7f79026e4 122 uint16_t data_index = 0;
Davidroid 20:9952bef19da1 123 uint32_t *coef_p = &coef[sincn][0];
Davidroid 20:9952bef19da1 124 int32_t F = 0;
Davidroid 20:9952bef19da1 125 uint8_t decimation = param->Decimation;
Davidroid 20:9952bef19da1 126 uint8_t channels = param->In_MicChannels;
davide.aliprandi@st.com 2:9f389fd8fb2e 127
Davidroid 20:9952bef19da1 128 for (i = 0; i < decimation; i += 8) {
davide.aliprandi@st.com 11:b2f7f79026e4 129 c = data[data_index];
davide.aliprandi@st.com 11:b2f7f79026e4 130 F += ((c >> 7) ) * coef_p[i ] +
davide.aliprandi@st.com 11:b2f7f79026e4 131 ((c >> 6) & 0x01) * coef_p[i + 1] +
davide.aliprandi@st.com 11:b2f7f79026e4 132 ((c >> 5) & 0x01) * coef_p[i + 2] +
davide.aliprandi@st.com 11:b2f7f79026e4 133 ((c >> 4) & 0x01) * coef_p[i + 3] +
davide.aliprandi@st.com 11:b2f7f79026e4 134 ((c >> 3) & 0x01) * coef_p[i + 4] +
davide.aliprandi@st.com 11:b2f7f79026e4 135 ((c >> 2) & 0x01) * coef_p[i + 5] +
davide.aliprandi@st.com 11:b2f7f79026e4 136 ((c >> 1) & 0x01) * coef_p[i + 6] +
davide.aliprandi@st.com 11:b2f7f79026e4 137 ((c ) & 0x01) * coef_p[i + 7];
davide.aliprandi@st.com 11:b2f7f79026e4 138 data_index += channels;
davide.aliprandi@st.com 2:9f389fd8fb2e 139 }
davide.aliprandi@st.com 2:9f389fd8fb2e 140 return F;
davide.aliprandi@st.com 2:9f389fd8fb2e 141 }
davide.aliprandi@st.com 15:17bdadc6aa9c 142 #endif
davide.aliprandi@st.com 2:9f389fd8fb2e 143
Davidroid 20:9952bef19da1 144 void convolve(uint32_t Signal[/* SignalLen */], unsigned short SignalLen,
Davidroid 20:9952bef19da1 145 uint32_t Kernel[/* KernelLen */], unsigned short KernelLen,
Davidroid 20:9952bef19da1 146 uint32_t Result[/* SignalLen + KernelLen - 1 */])
Davidroid 20:9952bef19da1 147 {
Davidroid 20:9952bef19da1 148 uint16_t n;
Davidroid 20:9952bef19da1 149
Davidroid 20:9952bef19da1 150 for (n = 0; n < SignalLen + KernelLen - 1; n++)
Davidroid 20:9952bef19da1 151 {
Davidroid 20:9952bef19da1 152 unsigned short kmin, kmax, k;
Davidroid 20:9952bef19da1 153
Davidroid 20:9952bef19da1 154 Result[n] = 0;
Davidroid 20:9952bef19da1 155
Davidroid 20:9952bef19da1 156 kmin = (n >= KernelLen - 1) ? n - (KernelLen - 1) : 0;
Davidroid 20:9952bef19da1 157 kmax = (n < SignalLen - 1) ? n : SignalLen - 1;
Davidroid 20:9952bef19da1 158
Davidroid 20:9952bef19da1 159 for (k = kmin; k <= kmax; k++) {
Davidroid 20:9952bef19da1 160 Result[n] += Signal[k] * Kernel[n - k];
Davidroid 20:9952bef19da1 161 }
Davidroid 20:9952bef19da1 162 }
Davidroid 20:9952bef19da1 163 }
Davidroid 20:9952bef19da1 164
davide.aliprandi@st.com 2:9f389fd8fb2e 165 void Open_PDM_Filter_Init(TPDMFilter_InitStruct *Param)
davide.aliprandi@st.com 2:9f389fd8fb2e 166 {
davide.aliprandi@st.com 16:4ab2eac7be21 167 uint16_t i, j;
davide.aliprandi@st.com 2:9f389fd8fb2e 168 int64_t sum = 0;
Davidroid 20:9952bef19da1 169
Davidroid 20:9952bef19da1 170 uint8_t decimation = Param->Decimation;
Davidroid 20:9952bef19da1 171
Davidroid 20:9952bef19da1 172 for (i = 0; i < SINCN; i++) {
davide.aliprandi@st.com 16:4ab2eac7be21 173 Param->Coef[i] = 0;
davide.aliprandi@st.com 16:4ab2eac7be21 174 Param->bit[i] = 0;
davide.aliprandi@st.com 2:9f389fd8fb2e 175 }
Davidroid 20:9952bef19da1 176 for (i = 0; i < decimation; i++) {
davide.aliprandi@st.com 16:4ab2eac7be21 177 sinc1[i] = 1;
davide.aliprandi@st.com 2:9f389fd8fb2e 178 }
davide.aliprandi@st.com 16:4ab2eac7be21 179
davide.aliprandi@st.com 16:4ab2eac7be21 180 Param->OldOut = Param->OldIn = Param->OldZ = 0;
Davidroid 20:9952bef19da1 181 Param->LP_ALFA = (Param->LP_HZ != 0 ? (uint16_t) (Param->LP_HZ * 256 / (Param->LP_HZ + Param->Fs / (2 * 3.14159))) : 0);
Davidroid 20:9952bef19da1 182 Param->HP_ALFA = (Param->HP_HZ != 0 ? (uint16_t) (Param->Fs * 256 / (2 * 3.14159 * Param->HP_HZ + Param->Fs)) : 0);
davide.aliprandi@st.com 16:4ab2eac7be21 183
Davidroid 20:9952bef19da1 184 Param->FilterLen = decimation * SINCN;
davide.aliprandi@st.com 16:4ab2eac7be21 185 sinc[0] = 0;
Davidroid 20:9952bef19da1 186 sinc[decimation * SINCN - 1] = 0;
Davidroid 20:9952bef19da1 187 convolve(sinc1, decimation, sinc1, decimation, sinc2);
Davidroid 20:9952bef19da1 188 convolve(sinc2, decimation * 2 - 1, sinc1, decimation, &sinc[1]);
Davidroid 20:9952bef19da1 189 for(j = 0; j < SINCN; j++) {
Davidroid 20:9952bef19da1 190 for (i = 0; i < decimation; i++) {
Davidroid 20:9952bef19da1 191 coef[j][i] = sinc[j * decimation + i];
Davidroid 20:9952bef19da1 192 sum += sinc[j * decimation + i];
davide.aliprandi@st.com 2:9f389fd8fb2e 193 }
davide.aliprandi@st.com 2:9f389fd8fb2e 194 }
davide.aliprandi@st.com 16:4ab2eac7be21 195
davide.aliprandi@st.com 16:4ab2eac7be21 196 sub_const = sum >> 1;
Davidroid 20:9952bef19da1 197 div_const = sub_const * Param->MaxVolume / 32768 / FILTER_GAIN;
davide.aliprandi@st.com 16:4ab2eac7be21 198 div_const = (div_const == 0 ? 1 : div_const);
davide.aliprandi@st.com 15:17bdadc6aa9c 199
davide.aliprandi@st.com 15:17bdadc6aa9c 200 #ifdef USE_LUT
davide.aliprandi@st.com 15:17bdadc6aa9c 201 /* Look-Up Table. */
davide.aliprandi@st.com 15:17bdadc6aa9c 202 uint16_t c, d, s;
Davidroid 20:9952bef19da1 203 for (s = 0; s < SINCN; s++)
davide.aliprandi@st.com 15:17bdadc6aa9c 204 {
davide.aliprandi@st.com 15:17bdadc6aa9c 205 uint32_t *coef_p = &coef[s][0];
davide.aliprandi@st.com 15:17bdadc6aa9c 206 for (c = 0; c < 256; c++)
Davidroid 20:9952bef19da1 207 for (d = 0; d < decimation / 8; d++)
davide.aliprandi@st.com 15:17bdadc6aa9c 208 lut[c][d][s] = ((c >> 7) ) * coef_p[d * 8 ] +
davide.aliprandi@st.com 15:17bdadc6aa9c 209 ((c >> 6) & 0x01) * coef_p[d * 8 + 1] +
davide.aliprandi@st.com 15:17bdadc6aa9c 210 ((c >> 5) & 0x01) * coef_p[d * 8 + 2] +
davide.aliprandi@st.com 15:17bdadc6aa9c 211 ((c >> 4) & 0x01) * coef_p[d * 8 + 3] +
davide.aliprandi@st.com 15:17bdadc6aa9c 212 ((c >> 3) & 0x01) * coef_p[d * 8 + 4] +
davide.aliprandi@st.com 15:17bdadc6aa9c 213 ((c >> 2) & 0x01) * coef_p[d * 8 + 5] +
davide.aliprandi@st.com 15:17bdadc6aa9c 214 ((c >> 1) & 0x01) * coef_p[d * 8 + 6] +
davide.aliprandi@st.com 15:17bdadc6aa9c 215 ((c ) & 0x01) * coef_p[d * 8 + 7];
davide.aliprandi@st.com 15:17bdadc6aa9c 216 }
davide.aliprandi@st.com 15:17bdadc6aa9c 217 #endif
davide.aliprandi@st.com 2:9f389fd8fb2e 218 }
davide.aliprandi@st.com 2:9f389fd8fb2e 219
Davidroid 20:9952bef19da1 220 void Open_PDM_Filter_64(uint8_t* data, uint16_t* dataOut, uint16_t volume, TPDMFilter_InitStruct *Param)
davide.aliprandi@st.com 2:9f389fd8fb2e 221 {
davide.aliprandi@st.com 16:4ab2eac7be21 222 uint8_t i, data_out_index;
davide.aliprandi@st.com 16:4ab2eac7be21 223 uint8_t channels = Param->In_MicChannels;
Davidroid 20:9952bef19da1 224 uint8_t data_inc = ((DECIMATION_MAX >> 4) * channels);
davide.aliprandi@st.com 16:4ab2eac7be21 225 int64_t Z, Z0, Z1, Z2;
Davidroid 20:9952bef19da1 226 int64_t OldOut, OldIn, OldZ;
davide.aliprandi@st.com 16:4ab2eac7be21 227
davide.aliprandi@st.com 16:4ab2eac7be21 228 OldOut = Param->OldOut;
davide.aliprandi@st.com 16:4ab2eac7be21 229 OldIn = Param->OldIn;
davide.aliprandi@st.com 16:4ab2eac7be21 230 OldZ = Param->OldZ;
davide.aliprandi@st.com 16:4ab2eac7be21 231
Davidroid 20:9952bef19da1 232 #ifdef USE_LUT
Davidroid 20:9952bef19da1 233 uint8_t j = channels - 1;
Davidroid 20:9952bef19da1 234 #endif
Davidroid 20:9952bef19da1 235
Davidroid 20:9952bef19da1 236 for (i = 0, data_out_index = 0; i < Param->Fs / 1000; i++, data_out_index += channels) {
davide.aliprandi@st.com 16:4ab2eac7be21 237 #ifdef USE_LUT
Davidroid 20:9952bef19da1 238 Z0 = filter_tables_64[j](data, 0);
Davidroid 20:9952bef19da1 239 Z1 = filter_tables_64[j](data, 1);
Davidroid 20:9952bef19da1 240 Z2 = filter_tables_64[j](data, 2);
davide.aliprandi@st.com 16:4ab2eac7be21 241 #else
Davidroid 20:9952bef19da1 242 Z0 = filter_table(data, 0, Param);
Davidroid 20:9952bef19da1 243 Z1 = filter_table(data, 1, Param);
Davidroid 20:9952bef19da1 244 Z2 = filter_table(data, 2, Param);
davide.aliprandi@st.com 16:4ab2eac7be21 245 #endif
davide.aliprandi@st.com 16:4ab2eac7be21 246
davide.aliprandi@st.com 16:4ab2eac7be21 247 Z = Param->Coef[1] + Z2 - sub_const;
davide.aliprandi@st.com 16:4ab2eac7be21 248 Param->Coef[1] = Param->Coef[0] + Z1;
davide.aliprandi@st.com 16:4ab2eac7be21 249 Param->Coef[0] = Z0;
davide.aliprandi@st.com 16:4ab2eac7be21 250
davide.aliprandi@st.com 16:4ab2eac7be21 251 OldOut = (Param->HP_ALFA * (OldOut + Z - OldIn)) >> 8;
davide.aliprandi@st.com 16:4ab2eac7be21 252 OldIn = Z;
Davidroid 20:9952bef19da1 253 OldZ = ((256 - Param->LP_ALFA) * OldZ + Param->LP_ALFA * OldOut) >> 8;
davide.aliprandi@st.com 16:4ab2eac7be21 254
Davidroid 20:9952bef19da1 255 Z = OldZ * volume;
davide.aliprandi@st.com 16:4ab2eac7be21 256 Z = RoundDiv(Z, div_const);
davide.aliprandi@st.com 16:4ab2eac7be21 257 Z = SaturaLH(Z, -32700, 32700);
davide.aliprandi@st.com 16:4ab2eac7be21 258
davide.aliprandi@st.com 16:4ab2eac7be21 259 dataOut[data_out_index] = Z;
davide.aliprandi@st.com 16:4ab2eac7be21 260 data += data_inc;
davide.aliprandi@st.com 16:4ab2eac7be21 261 }
davide.aliprandi@st.com 16:4ab2eac7be21 262
davide.aliprandi@st.com 16:4ab2eac7be21 263 Param->OldOut = OldOut;
davide.aliprandi@st.com 16:4ab2eac7be21 264 Param->OldIn = OldIn;
davide.aliprandi@st.com 16:4ab2eac7be21 265 Param->OldZ = OldZ;
davide.aliprandi@st.com 2:9f389fd8fb2e 266 }
Davidroid 20:9952bef19da1 267
Davidroid 20:9952bef19da1 268 void Open_PDM_Filter_128(uint8_t* data, uint16_t* dataOut, uint16_t volume, TPDMFilter_InitStruct *Param)
Davidroid 20:9952bef19da1 269 {
Davidroid 20:9952bef19da1 270 uint8_t i, data_out_index;
Davidroid 20:9952bef19da1 271 uint8_t channels = Param->In_MicChannels;
Davidroid 20:9952bef19da1 272 uint8_t data_inc = ((DECIMATION_MAX >> 3) * channels);
Davidroid 20:9952bef19da1 273 int64_t Z, Z0, Z1, Z2;
Davidroid 20:9952bef19da1 274 int64_t OldOut, OldIn, OldZ;
Davidroid 20:9952bef19da1 275
Davidroid 20:9952bef19da1 276 OldOut = Param->OldOut;
Davidroid 20:9952bef19da1 277 OldIn = Param->OldIn;
Davidroid 20:9952bef19da1 278 OldZ = Param->OldZ;
Davidroid 20:9952bef19da1 279
Davidroid 20:9952bef19da1 280 #ifdef USE_LUT
Davidroid 20:9952bef19da1 281 uint8_t j = channels - 1;
Davidroid 20:9952bef19da1 282 #endif
Davidroid 20:9952bef19da1 283
Davidroid 20:9952bef19da1 284 for (i = 0, data_out_index = 0; i < Param->Fs / 1000; i++, data_out_index += channels) {
Davidroid 20:9952bef19da1 285 #ifdef USE_LUT
Davidroid 20:9952bef19da1 286 Z0 = filter_tables_128[j](data, 0);
Davidroid 20:9952bef19da1 287 Z1 = filter_tables_128[j](data, 1);
Davidroid 20:9952bef19da1 288 Z2 = filter_tables_128[j](data, 2);
Davidroid 20:9952bef19da1 289 #else
Davidroid 20:9952bef19da1 290 Z0 = filter_table(data, 0, Param);
Davidroid 20:9952bef19da1 291 Z1 = filter_table(data, 1, Param);
Davidroid 20:9952bef19da1 292 Z2 = filter_table(data, 2, Param);
Davidroid 20:9952bef19da1 293 #endif
Davidroid 20:9952bef19da1 294
Davidroid 20:9952bef19da1 295 Z = Param->Coef[1] + Z2 - sub_const;
Davidroid 20:9952bef19da1 296 Param->Coef[1] = Param->Coef[0] + Z1;
Davidroid 20:9952bef19da1 297 Param->Coef[0] = Z0;
Davidroid 20:9952bef19da1 298
Davidroid 20:9952bef19da1 299 OldOut = (Param->HP_ALFA * (OldOut + Z - OldIn)) >> 8;
Davidroid 20:9952bef19da1 300 OldIn = Z;
Davidroid 20:9952bef19da1 301 OldZ = ((256 - Param->LP_ALFA) * OldZ + Param->LP_ALFA * OldOut) >> 8;
Davidroid 20:9952bef19da1 302
Davidroid 20:9952bef19da1 303 Z = OldZ * volume;
Davidroid 20:9952bef19da1 304 Z = RoundDiv(Z, div_const);
Davidroid 20:9952bef19da1 305 Z = SaturaLH(Z, -32700, 32700);
Davidroid 20:9952bef19da1 306
Davidroid 20:9952bef19da1 307 dataOut[data_out_index] = Z;
Davidroid 20:9952bef19da1 308 data += data_inc;
Davidroid 20:9952bef19da1 309 }
Davidroid 20:9952bef19da1 310
Davidroid 20:9952bef19da1 311 Param->OldOut = OldOut;
Davidroid 20:9952bef19da1 312 Param->OldIn = OldIn;
Davidroid 20:9952bef19da1 313 Param->OldZ = OldZ;
Davidroid 20:9952bef19da1 314 }