pdm_microphone.h

/*
 * Copyright (c) 2021 Arm Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: Apache-2.0
 * 
 */
 
#ifndef _PICO_PDM_MICROPHONE_H_
#define _PICO_PDM_MICROPHONE_H_
 
#include "hardware/pio.h"
 
typedef void (*pdm_samples_ready_handler_t)(void);
 
struct pdm_microphone_config {
    uint gpio_data;
    uint gpio_clk;
    PIO pio;
    uint pio_sm;
    uint sample_rate;
    uint sample_buffer_size;
};
 
int pdm_microphone_init(const struct pdm_microphone_config* config);
void pdm_microphone_deinit();
 
int pdm_microphone_start();
void pdm_microphone_stop();
 
void pdm_microphone_set_samples_ready_handler(pdm_samples_ready_handler_t handler);
void pdm_microphone_set_filter_max_volume(uint8_t max_volume);
void pdm_microphone_set_filter_gain(uint8_t gain);
void pdm_microphone_set_filter_volume(uint16_t volume);
 
int pdm_microphone_read(int16_t* buffer, size_t samples);
 
#endif