Quentin Roche / X_NUCLEO_CCA02M1

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Dependencies:   ST_FREQUENCY_DIVIDER ST_I2S USBDEVICE

Fork of X_NUCLEO_CCA02M1 by ST

BSP/PDM2PCMAudio_class.cpp@0:d5552d432108, 2017-02-28 (annotated)

Committer:
davide.aliprandi@st.com
Date:
Tue Feb 28 11:20:53 2017 +0100
Revision:
0:d5552d432108
Library to handle the X-NUCLEO-CCA02M1 MEMS Microphones Expansion Board.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
davide.aliprandi@st.com 0:d5552d432108 1 /**
davide.aliprandi@st.com 0:d5552d432108 2 ******************************************************************************
davide.aliprandi@st.com 0:d5552d432108 3 * @file PDM2PCMAudio_class.cpp
davide.aliprandi@st.com 0:d5552d432108 4 * @author AST / Software Platforms and Cloud
davide.aliprandi@st.com 0:d5552d432108 5 * @version V1.0
davide.aliprandi@st.com 0:d5552d432108 6 * @date November 10th, 2016
davide.aliprandi@st.com 0:d5552d432108 7 * @brief Implementation file for the PDM2PCMAudio conversion library.
davide.aliprandi@st.com 0:d5552d432108 8 ******************************************************************************
davide.aliprandi@st.com 0:d5552d432108 9 * @attention
davide.aliprandi@st.com 0:d5552d432108 10 *
davide.aliprandi@st.com 0:d5552d432108 11 * <h2><center>&copy; COPYRIGHT(c) 2015 STMicroelectronics</center></h2>
davide.aliprandi@st.com 0:d5552d432108 12 *
davide.aliprandi@st.com 0:d5552d432108 13 * Redistribution and use in source and binary forms, with or without modification,
davide.aliprandi@st.com 0:d5552d432108 14 * are permitted provided that the following conditions are met:
davide.aliprandi@st.com 0:d5552d432108 15 * 1. Redistributions of source code must retain the above copyright notice,
davide.aliprandi@st.com 0:d5552d432108 16 * this list of conditions and the following disclaimer.
davide.aliprandi@st.com 0:d5552d432108 17 * 2. Redistributions in binary form must reproduce the above copyright notice,
davide.aliprandi@st.com 0:d5552d432108 18 * this list of conditions and the following disclaimer in the documentation
davide.aliprandi@st.com 0:d5552d432108 19 * and/or other materials provided with the distribution.
davide.aliprandi@st.com 0:d5552d432108 20 * 3. Neither the name of STMicroelectronics nor the names of its contributors
davide.aliprandi@st.com 0:d5552d432108 21 * may be used to endorse or promote products derived from this software
davide.aliprandi@st.com 0:d5552d432108 22 * without specific prior written permission.
davide.aliprandi@st.com 0:d5552d432108 23 *
davide.aliprandi@st.com 0:d5552d432108 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
davide.aliprandi@st.com 0:d5552d432108 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
davide.aliprandi@st.com 0:d5552d432108 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
davide.aliprandi@st.com 0:d5552d432108 27 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
davide.aliprandi@st.com 0:d5552d432108 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
davide.aliprandi@st.com 0:d5552d432108 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
davide.aliprandi@st.com 0:d5552d432108 30 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
davide.aliprandi@st.com 0:d5552d432108 31 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
davide.aliprandi@st.com 0:d5552d432108 32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
davide.aliprandi@st.com 0:d5552d432108 33 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
davide.aliprandi@st.com 0:d5552d432108 34 *
davide.aliprandi@st.com 0:d5552d432108 35 ******************************************************************************
davide.aliprandi@st.com 0:d5552d432108 36 */
davide.aliprandi@st.com 0:d5552d432108 37
davide.aliprandi@st.com 0:d5552d432108 38
davide.aliprandi@st.com 0:d5552d432108 39 /* Includes ------------------------------------------------------------------*/
davide.aliprandi@st.com 0:d5552d432108 40
davide.aliprandi@st.com 0:d5552d432108 41 #include "PDM2PCMAudio_class.h"
davide.aliprandi@st.com 0:d5552d432108 42
davide.aliprandi@st.com 0:d5552d432108 43
davide.aliprandi@st.com 0:d5552d432108 44 /* Variables -----------------------------------------------------------------*/
davide.aliprandi@st.com 0:d5552d432108 45
davide.aliprandi@st.com 0:d5552d432108 46 /* Demux filter. */
davide.aliprandi@st.com 0:d5552d432108 47 const uint8_t PDM2PCMAudio::_demux_filter[DEMUX_FILTER_SIZE] =
davide.aliprandi@st.com 0:d5552d432108 48 {
davide.aliprandi@st.com 0:d5552d432108 49 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03,
davide.aliprandi@st.com 0:d5552d432108 50 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03,
davide.aliprandi@st.com 0:d5552d432108 51 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07,
davide.aliprandi@st.com 0:d5552d432108 52 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07,
davide.aliprandi@st.com 0:d5552d432108 53 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03,
davide.aliprandi@st.com 0:d5552d432108 54 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03,
davide.aliprandi@st.com 0:d5552d432108 55 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07,
davide.aliprandi@st.com 0:d5552d432108 56 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07,
davide.aliprandi@st.com 0:d5552d432108 57 0x08, 0x09, 0x08, 0x09, 0x0a, 0x0b, 0x0a, 0x0b,
davide.aliprandi@st.com 0:d5552d432108 58 0x08, 0x09, 0x08, 0x09, 0x0a, 0x0b, 0x0a, 0x0b,
davide.aliprandi@st.com 0:d5552d432108 59 0x0c, 0x0d, 0x0c, 0x0d, 0x0e, 0x0f, 0x0e, 0x0f,
davide.aliprandi@st.com 0:d5552d432108 60 0x0c, 0x0d, 0x0c, 0x0d, 0x0e, 0x0f, 0x0e, 0x0f,
davide.aliprandi@st.com 0:d5552d432108 61 0x08, 0x09, 0x08, 0x09, 0x0a, 0x0b, 0x0a, 0x0b,
davide.aliprandi@st.com 0:d5552d432108 62 0x08, 0x09, 0x08, 0x09, 0x0a, 0x0b, 0x0a, 0x0b,
davide.aliprandi@st.com 0:d5552d432108 63 0x0c, 0x0d, 0x0c, 0x0d, 0x0e, 0x0f, 0x0e, 0x0f,
davide.aliprandi@st.com 0:d5552d432108 64 0x0c, 0x0d, 0x0c, 0x0d, 0x0e, 0x0f, 0x0e, 0x0f
davide.aliprandi@st.com 0:d5552d432108 65 };
davide.aliprandi@st.com 0:d5552d432108 66
davide.aliprandi@st.com 0:d5552d432108 67
davide.aliprandi@st.com 0:d5552d432108 68 /* Methods -------------------------------------------------------------------*/
davide.aliprandi@st.com 0:d5552d432108 69
davide.aliprandi@st.com 0:d5552d432108 70 /**
davide.aliprandi@st.com 0:d5552d432108 71 * @brief Converting audio data from PDM to PCM.
davide.aliprandi@st.com 0:d5552d432108 72 * @param output_buffer Pointer to output PCM buffer data.
davide.aliprandi@st.com 0:d5552d432108 73 * @param input_buffer Pointer to input PDM buffer data.
davide.aliprandi@st.com 0:d5552d432108 74 * @param volume Volume level (it must be in the range [0..64]).
davide.aliprandi@st.com 0:d5552d432108 75 * @param decimation_factor Decimation factor (it must be either 64 or 128).
davide.aliprandi@st.com 0:d5552d432108 76 * @retval COMPONENT_OK in case of success, COMPONENT_ERROR otherwise.
davide.aliprandi@st.com 0:d5552d432108 77 */
davide.aliprandi@st.com 0:d5552d432108 78 Status_t PDM2PCMAudio::Convert(int16_t *output_buffer, uint16_t *input_buffer, uint32_t volume, uint32_t decimation_factor)
davide.aliprandi@st.com 0:d5552d432108 79 {
davide.aliprandi@st.com 0:d5552d432108 80 if (!(volume <= PDM2PCM_MAX_VOLUME))
davide.aliprandi@st.com 0:d5552d432108 81 error("Volume level not supported: it must be in the range [0..64].\r\n");
davide.aliprandi@st.com 0:d5552d432108 82
davide.aliprandi@st.com 0:d5552d432108 83 switch (decimation_factor)
davide.aliprandi@st.com 0:d5552d432108 84 {
davide.aliprandi@st.com 0:d5552d432108 85 case 64:
davide.aliprandi@st.com 0:d5552d432108 86 for (uint32_t index = 0; index < _channels; index++)
davide.aliprandi@st.com 0:d5552d432108 87 PDM_Filter_64_LSB(&((uint8_t *) input_buffer)[index], (uint16_t *) &(output_buffer[index]), volume, (PDMFilter_InitStruct *) &_PDM2PCM_filter[index]);
davide.aliprandi@st.com 0:d5552d432108 88 break;
davide.aliprandi@st.com 0:d5552d432108 89
davide.aliprandi@st.com 0:d5552d432108 90 case 128:
davide.aliprandi@st.com 0:d5552d432108 91 for (uint32_t index = 0; index < _channels; index++)
davide.aliprandi@st.com 0:d5552d432108 92 PDM_Filter_128_LSB(&((uint8_t *) input_buffer)[index], (uint16_t *) &(output_buffer[index]), volume, (PDMFilter_InitStruct *) &_PDM2PCM_filter[index]);
davide.aliprandi@st.com 0:d5552d432108 93 break;
davide.aliprandi@st.com 0:d5552d432108 94
davide.aliprandi@st.com 0:d5552d432108 95 default:
davide.aliprandi@st.com 0:d5552d432108 96 error("Decimation factor not supported: it must be either 64 or 128.\r\n");
davide.aliprandi@st.com 0:d5552d432108 97 }
davide.aliprandi@st.com 0:d5552d432108 98
davide.aliprandi@st.com 0:d5552d432108 99 return COMPONENT_OK;
davide.aliprandi@st.com 0:d5552d432108 100 }
davide.aliprandi@st.com 0:d5552d432108 101
davide.aliprandi@st.com 0:d5552d432108 102 /**
davide.aliprandi@st.com 0:d5552d432108 103 * @brief Scrambling audio data.
davide.aliprandi@st.com 0:d5552d432108 104 * @param output_buffer Pointer to output PDM buffer data.
davide.aliprandi@st.com 0:d5552d432108 105 * @param input_buffer Pointer to input PDM buffer data.
davide.aliprandi@st.com 0:d5552d432108 106 * @param size Size of the buffers (thay has to be equally sized).
davide.aliprandi@st.com 0:d5552d432108 107 * @retval COMPONENT_OK in case of success, COMPONENT_ERROR otherwise.
davide.aliprandi@st.com 0:d5552d432108 108 */
davide.aliprandi@st.com 0:d5552d432108 109 Status_t PDM2PCMAudio::Scramble(uint16_t *output_buffer, uint16_t *input_buffer, uint32_t size)
davide.aliprandi@st.com 0:d5552d432108 110 {
davide.aliprandi@st.com 0:d5552d432108 111 for (uint32_t index = 0; index < size; index++)
davide.aliprandi@st.com 0:d5552d432108 112 output_buffer[index] = HTONS(input_buffer[index]);
davide.aliprandi@st.com 0:d5552d432108 113
davide.aliprandi@st.com 0:d5552d432108 114 return COMPONENT_OK;
davide.aliprandi@st.com 0:d5552d432108 115 }
davide.aliprandi@st.com 0:d5552d432108 116
davide.aliprandi@st.com 0:d5552d432108 117 /**s
davide.aliprandi@st.com 0:d5552d432108 118 * @brief Demuxing audio data.
davide.aliprandi@st.com 0:d5552d432108 119 * @param output_buffer Pointer to output PDM buffer data.
davide.aliprandi@st.com 0:d5552d432108 120 * @param input_buffer Pointer to input PDM buffer data.
davide.aliprandi@st.com 0:d5552d432108 121 * @param size Size of the buffers (thay has to be equally sized).
davide.aliprandi@st.com 0:d5552d432108 122 * @retval COMPONENT_OK in case of success, COMPONENT_ERROR otherwise.
davide.aliprandi@st.com 0:d5552d432108 123 */
davide.aliprandi@st.com 0:d5552d432108 124 Status_t PDM2PCMAudio::Demux(uint16_t *output_buffer, uint16_t *input_buffer, uint32_t size)
davide.aliprandi@st.com 0:d5552d432108 125 {
davide.aliprandi@st.com 0:d5552d432108 126 for (uint32_t index = 0; index < size; index++)
davide.aliprandi@st.com 0:d5552d432108 127 {
davide.aliprandi@st.com 0:d5552d432108 128 uint8_t a = ((uint8_t *) input_buffer)[index * 2];
davide.aliprandi@st.com 0:d5552d432108 129 uint8_t b = ((uint8_t *) input_buffer)[index * 2 + 1];
davide.aliprandi@st.com 0:d5552d432108 130 ((uint8_t *) (output_buffer))[index * 2] = _demux_filter[a & DEMUX_FILTER_MASK] | _demux_filter[b & DEMUX_FILTER_MASK] << 4;
davide.aliprandi@st.com 0:d5552d432108 131 ((uint8_t *) (output_buffer))[index * 2 + 1] = _demux_filter[(a >> 1) & DEMUX_FILTER_MASK] | _demux_filter[(b >> 1) & DEMUX_FILTER_MASK] << 4;
davide.aliprandi@st.com 0:d5552d432108 132 }
davide.aliprandi@st.com 0:d5552d432108 133
davide.aliprandi@st.com 0:d5552d432108 134 return COMPONENT_OK;
davide.aliprandi@st.com 0:d5552d432108 135 }
davide.aliprandi@st.com 0:d5552d432108 136
davide.aliprandi@st.com 0:d5552d432108 137 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/