/* * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ #pragma once #include "esp_types.h" #include "esp_err.h" #include "driver/i2s_types.h" #include "hal/i2s_types.h" #ifdef __cplusplus extern "C" { #endif /** * @brief PDM format in 2 slots(RX) * @param bits_per_sample I2S data bit width, only support 16 bits for PDM mode * @param mono_or_stereo I2S_SLOT_MODE_MONO or I2S_SLOT_MODE_STEREO */ #define LP_I2S_PDM_RX_SLOT_DEFAULT_CONFIG(bits_per_sample, mono_or_stereo) { \ .data_bit_width = bits_per_sample, \ .slot_bit_width = I2S_SLOT_BIT_WIDTH_AUTO, \ .slot_mode = mono_or_stereo, \ .slot_mask = (mono_or_stereo == I2S_SLOT_MODE_MONO) ? \ I2S_PDM_SLOT_LEFT : I2S_PDM_SLOT_BOTH, \ .hp_en = true, \ .hp_cut_off_freq_hz = 35.5, \ .amplify_num = 1, \ } /** * @brief LP I2S pin configurations */ typedef struct { int clk; /*!< clk pin number */ int din; /*!< din pin number */ } lp_i2s_pdm_rx_gpio_config_t; /* High Pass Filter Cut-off Frequency Sheet +----------------+------------------+----------------+------------------+----------------+------------------+ | param0, param5 | cut-off freq(Hz) | param0, param5 | cut-off freq(Hz) | param0, param5 | cut-off freq(Hz) | +----------------+------------------+----------------+------------------+----------------+------------------+ | (0, 0) | 185 | (3, 3) | 115 | (5, 5) | 69 | | (0, 1) | 172 | (1, 7) | 106 | (4, 7) | 63 | | (1, 1) | 160 | (2, 4) | 104 | (5, 6) | 58 | | (1, 2) | 150 | (4, 4) | 92 | (5, 7) | 49 | | (2, 2) | 137 | (2, 7) | 91.5 | (6, 6) | 46 | | (2, 3) | 126 | (4, 5) | 81 | (6, 7) | 35.5 | | (0, 3) | 120 | (3, 7) | 77.2 | (7, 7) | 23.3 | +----------------+------------------+----------------+------------------+----------------+------------------+ */ /** * @brief I2S slot configuration for PDM RX mode */ typedef struct { /* General fields */ i2s_data_bit_width_t data_bit_width; /*!< I2S sample data bit width (valid data bits per sample), only support 16 bits for PDM mode */ i2s_slot_bit_width_t slot_bit_width; /*!< I2S slot bit width (total bits per slot) , only support 16 bits for PDM mode */ i2s_slot_mode_t slot_mode; /*!< Set mono or stereo mode with I2S_SLOT_MODE_MONO or I2S_SLOT_MODE_STEREO */ /* Particular fields */ i2s_pdm_slot_mask_t slot_mask; /*!< Choose the slots to activate */ bool ws_pol; /*!< WS signal polarity, set true to enable high lever first */ bool hp_en; /*!< High pass filter enable */ float hp_cut_off_freq_hz; /*!< High pass filter cut-off frequency, range 23.3Hz ~ 185Hz, see cut-off frequency sheet above */ uint32_t amplify_num; /*!< The amplification number of the final conversion result. * The data that have converted from PDM to PCM module, will time `amplify_num` additionally to amplify the final result. * Note that it's only a multiplier of the digital PCM data, not the gain of the analog signal * range 1~15, default 1 */ } lp_i2s_pdm_rx_slot_config_t; /** * @brief LP I2S PDM configuration */ typedef struct { lp_i2s_pdm_rx_gpio_config_t pin_cfg; /*!< Pin configuration */ lp_i2s_pdm_rx_slot_config_t slot_cfg; /*!< PDM mode slot configuration */ /* LP I2S only support slave mode, not support to configure the clock */ } lp_i2s_pdm_rx_config_t; /** * @brief Init LP I2S to PDM mode * * @param[in] handle LP I2S channel handle * @param[in] pdm_cfg PDM configuration * * @return * - ESP_OK: On success * - ESP_ERR_INVALID_ARG: Invalid argument * - ESP_ERR_INVALID_STATE: Invalid state */ esp_err_t lp_i2s_channel_init_pdm_rx_mode(lp_i2s_chan_handle_t handle, const lp_i2s_pdm_rx_config_t *pdm_cfg); #ifdef __cplusplus } #endif