64 lines
1.6 KiB
C++
64 lines
1.6 KiB
C++
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/**
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* Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
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*
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* SPDX-License-Identifier: BSD-3-Clause
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*/
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#pragma once
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#include "pico/audio_i2s.h"
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#define SAMPLES_PER_BUFFER 256
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typedef int16_t (*buffer_callback)(void);
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struct audio_buffer_pool *init_audio(uint32_t sample_rate, uint8_t pin_data, uint8_t pin_bclk, uint8_t pio_sm=0, uint8_t dma_ch=0) {
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static audio_format_t audio_format = {
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.sample_freq = sample_rate,
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.format = AUDIO_BUFFER_FORMAT_PCM_S16,
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.channel_count = 1,
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};
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static struct audio_buffer_format producer_format = {
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.format = &audio_format,
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.sample_stride = 2
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};
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struct audio_buffer_pool *producer_pool = audio_new_producer_pool(
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&producer_format,
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3,
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SAMPLES_PER_BUFFER
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);
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const struct audio_format *output_format;
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struct audio_i2s_config config = {
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.data_pin = pin_data,
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.clock_pin_base = pin_bclk,
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.dma_channel = dma_ch,
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.pio_sm = pio_sm,
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};
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output_format = audio_i2s_setup(&audio_format, &config);
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if (!output_format) {
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panic("PicoAudio: Unable to open audio device.\n");
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}
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bool status = audio_i2s_connect(producer_pool);
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if (!status) {
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panic("PicoAudio: Unable to connect to audio device.\n");
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}
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audio_i2s_set_enabled(true);
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return producer_pool;
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}
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void update_buffer(struct audio_buffer_pool *ap, buffer_callback cb) {
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struct audio_buffer *buffer = take_audio_buffer(ap, true);
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int16_t *samples = (int16_t *) buffer->buffer->bytes;
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for (uint i = 0; i < buffer->max_sample_count; i++) {
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samples[i] = cb();
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}
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buffer->sample_count = buffer->max_sample_count;
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give_audio_buffer(ap, buffer);
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}
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