e2565e2305
.. via a peripheral known as the "MQS" (medium quality sound). It uses an ~192kHz PWM signal to generate audio. It sounds OK on a small speaker with no amplifier. There's a small pop when starting/stopping audio, as is typical.
46 lines
1.7 KiB
C
46 lines
1.7 KiB
C
/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2020 Jeff Epler for Adafruit Industries
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#pragma once
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#if CIRCUITPY_AUDIOBUSIO_I2SOUT
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#include "supervisor/background_callback.h"
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#include "common-hal/microcontroller/Pin.h"
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#include "common-hal/audiobusio/__init__.h"
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// Some boards don't implement I2SOut, so suppress any routines from here.
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typedef struct {
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mp_obj_base_t base;
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i2s_t i2s;
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const mcu_pin_obj_t *bit_clock;
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const mcu_pin_obj_t *word_select;
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const mcu_pin_obj_t *data;
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} audiobusio_i2sout_obj_t;
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#endif
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