Merge pull request #2000 from jepler/nrf-pwm-audio

Implement PWM audio out for the nrf port

9 files changed, 469 insertions, 16 deletions

diff --git a/shared-bindings/audiobusio/I2SOut.c b/shared-bindings/audiobusio/I2SOut.c
index 980f11392..9bce9c760 100644
--- a/shared-bindings/audiobusio/I2SOut.c
+++ b/shared-bindings/audiobusio/I2SOut.c
@@ -56,7 +56,7 @@
 //|   using `UDA1334 Breakout <https://www.adafruit.com/product/3678>`_::
 //|
 //|     import audiobusio
-//|     import audioio
+//|     import audiocore
 //|     import board
 //|     import array
 //|     import time
@@ -68,7 +68,7 @@
 //|     for i in range(length):
 //|         sine_wave[i] = int(math.sin(math.pi * 2 * i / 18) * (2 ** 15) + 2 ** 15)
 //|
-//|     sine_wave = audiobusio.RawSample(sine_wave, sample_rate=8000)
+//|     sine_wave = audiocore.RawSample(sine_wave, sample_rate=8000)
 //|     i2s = audiobusio.I2SOut(board.D1, board.D0, board.D9)
 //|     i2s.play(sine_wave, loop=True)
 //|     time.sleep(1)
@@ -78,12 +78,13 @@
 //|
 //|     import board
 //|     import audioio
+//|     import audiocore
 //|     import audiobusio
 //|     import digitalio
 //|
 //|
 //|     f = open("cplay-5.1-16bit-16khz.wav", "rb")
-//|     wav = audioio.WaveFile(f)
+//|     wav = audiocore.WaveFile(f)
 //|
 //|     a = audiobusio.I2SOut(board.D1, board.D0, board.D9)
 //|
@@ -163,7 +164,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(audiobusio_i2sout___exit___obj, 4, 4,
 //|     Plays the sample once when loop=False and continuously when loop=True.
 //|     Does not block. Use `playing` to block.
 //|
-//|     Sample must be an `audioio.WaveFile` or `audioio.RawSample`.
+//|     Sample must be an `audiocore.WaveFile`, `audiocore.RawSample`, or `audiocore.Mixer`.
 //|
 //|     The sample itself should consist of 8 bit or 16 bit samples.
 //|
diff --git a/shared-bindings/audiocore/Mixer.c b/shared-bindings/audiocore/Mixer.c
index b2f0a3fda..9ab720434 100644
--- a/shared-bindings/audiocore/Mixer.c
+++ b/shared-bindings/audiocore/Mixer.c
@@ -36,7 +36,7 @@
 #include "shared-bindings/util.h"
 #include "supervisor/shared/translate.h"
 
-//| .. currentmodule:: audioio
+//| .. currentmodule:: audiocore
 //|
 //| :class:`Mixer` -- Mixes one or more audio samples together
 //| ===========================================================
@@ -54,15 +54,16 @@
 //|
 //|     import board
 //|     import audioio
+//|     import audiocore
 //|     import digitalio
 //|
 //|     # Required for CircuitPlayground Express
 //|     speaker_enable = digitalio.DigitalInOut(board.SPEAKER_ENABLE)
 //|     speaker_enable.switch_to_output(value=True)
 //|
-//|     music = audioio.WaveFile(open("cplay-5.1-16bit-16khz.wav", "rb"))
-//|     drum = audioio.WaveFile(open("drum.wav", "rb"))
-//|     mixer = audioio.Mixer(voice_count=2, sample_rate=16000, channel_count=1, bits_per_sample=16, samples_signed=True)
+//|     music = audiocore.WaveFile(open("cplay-5.1-16bit-16khz.wav", "rb"))
+//|     drum = audiocore.WaveFile(open("drum.wav", "rb"))
+//|     mixer = audiocore.Mixer(voice_count=2, sample_rate=16000, channel_count=1, bits_per_sample=16, samples_signed=True)
 //|     a = audioio.AudioOut(board.A0)
 //|
 //|     print("playing")
@@ -151,7 +152,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(audioio_mixer___exit___obj, 4, 4, aud
 //|     Plays the sample once when loop=False and continuously when loop=True.
 //|     Does not block. Use `playing` to block.
 //|
-//|     Sample must be an `audioio.WaveFile`, `audioio.Mixer` or `audioio.RawSample`.
+//|     Sample must be an `audiocore.WaveFile`, `audiocore.RawSample`, or `audiocore.Mixer`.
 //|
 //|     The sample must match the Mixer's encoding settings given in the constructor.
 //|
diff --git a/shared-bindings/audiocore/RawSample.c b/shared-bindings/audiocore/RawSample.c
index 912b48bfb..07f8c683f 100644
--- a/shared-bindings/audiocore/RawSample.c
+++ b/shared-bindings/audiocore/RawSample.c
@@ -35,7 +35,7 @@
 #include "shared-bindings/audiocore/RawSample.h"
 #include "supervisor/shared/translate.h"
 
-//| .. currentmodule:: audioio
+//| .. currentmodule:: audiocore
 //|
 //| :class:`RawSample` -- A raw audio sample buffer
 //| ========================================================
@@ -55,6 +55,7 @@
 //|
 //|   Simple 8ksps 440 Hz sin wave::
 //|
+//|     import audiocore
 //|     import audioio
 //|     import board
 //|     import array
@@ -68,7 +69,7 @@
 //|         sine_wave[i] = int(math.sin(math.pi * 2 * i / 18) * (2 ** 15))
 //|
 //|     dac = audioio.AudioOut(board.SPEAKER)
-//|     sine_wave = audioio.RawSample(sine_wave)
+//|     sine_wave = audiocore.RawSample(sine_wave)
 //|     dac.play(sine_wave, loop=True)
 //|     time.sleep(1)
 //|     dac.stop()
diff --git a/shared-bindings/audiocore/WaveFile.c b/shared-bindings/audiocore/WaveFile.c
index 4c1993b7c..edb190d3a 100644
--- a/shared-bindings/audiocore/WaveFile.c
+++ b/shared-bindings/audiocore/WaveFile.c
@@ -33,7 +33,7 @@
 #include "shared-bindings/util.h"
 #include "supervisor/shared/translate.h"
 
-//| .. currentmodule:: audioio
+//| .. currentmodule:: audiocore
 //|
 //| :class:`WaveFile` -- Load a wave file for audio playback
 //| ========================================================
@@ -50,6 +50,7 @@
 //|   Playing a wave file from flash::
 //|
 //|     import board
+//|     import audiocore
 //|     import audioio
 //|     import digitalio
 //|
@@ -58,7 +59,7 @@
 //|     speaker_enable.switch_to_output(value=True)
 //|
 //|     data = open("cplay-5.1-16bit-16khz.wav", "rb")
-//|     wav = audioio.WaveFile(data)
+//|     wav = audiocore.WaveFile(data)
 //|     a = audioio.AudioOut(board.A0)
 //|
 //|     print("playing")
diff --git a/shared-bindings/audioio/AudioOut.c b/shared-bindings/audioio/AudioOut.c
index 79df66f7d..af2fce48e 100644
--- a/shared-bindings/audioio/AudioOut.c
+++ b/shared-bindings/audioio/AudioOut.c
@@ -55,6 +55,7 @@
 //|
 //|   Simple 8ksps 440 Hz sin wave::
 //|
+//|     import audiocore
 //|     import audioio
 //|     import board
 //|     import array
@@ -68,7 +69,7 @@
 //|         sine_wave[i] = int(math.sin(math.pi * 2 * i / 18) * (2 ** 15) + 2 ** 15)
 //|
 //|     dac = audioio.AudioOut(board.SPEAKER)
-//|     sine_wave = audioio.RawSample(sine_wave, sample_rate=8000)
+//|     sine_wave = audiocore.RawSample(sine_wave, sample_rate=8000)
 //|     dac.play(sine_wave, loop=True)
 //|     time.sleep(1)
 //|     dac.stop()
@@ -84,7 +85,7 @@
 //|     speaker_enable.switch_to_output(value=True)
 //|
 //|     data = open("cplay-5.1-16bit-16khz.wav", "rb")
-//|     wav = audioio.WaveFile(data)
+//|     wav = audiocore.WaveFile(data)
 //|     a = audioio.AudioOut(board.A0)
 //|
 //|     print("playing")
@@ -162,7 +163,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(audioio_audioout___exit___obj, 4, 4,
 //|     Plays the sample once when loop=False and continuously when loop=True.
 //|     Does not block. Use `playing` to block.
 //|
-//|     Sample must be an `audioio.WaveFile` or `audioio.RawSample`.
+//|     Sample must be an `audiocore.WaveFile`, `audiocore.RawSample`, or `audiocore.Mixer`.
 //|
 //|     The sample itself should consist of 16 bit samples. Microcontrollers with a lower output
 //|     resolution will use the highest order bits to output. For example, the SAMD21 has a 10 bit
diff --git a/shared-bindings/audiopwmio/PWMAudioOut.c b/shared-bindings/audiopwmio/PWMAudioOut.c
new file mode 100644
index 000000000..92543d112
--- /dev/null
+++ b/shared-bindings/audiopwmio/PWMAudioOut.c
@@ -0,0 +1,294 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdint.h>
+
+#include "lib/utils/context_manager_helpers.h"
+#include "py/binary.h"
+#include "py/objproperty.h"
+#include "py/runtime.h"
+#include "shared-bindings/microcontroller/Pin.h"
+#include "shared-bindings/audiopwmio/PWMAudioOut.h"
+#include "shared-bindings/audiocore/RawSample.h"
+#include "shared-bindings/util.h"
+#include "supervisor/shared/translate.h"
+
+//| .. currentmodule:: audiopwmio
+//|
+//| :class:`PWMAudioOut` -- Output an analog audio signal
+//| ========================================================
+//|
+//| AudioOut can be used to output an analog audio signal on a given pin.
+//|
+//| .. class:: PWMAudioOut(left_channel, *, right_channel=None, quiescent_value=0x8000)
+//|
+//|   Create a PWMAudioOut object associated with the given pin(s). This allows you to
+//|   play audio signals out on the given pin(s).  In contrast to mod:`audioio`,
+//|   the pin(s) specified are digital pins, and are driven with a device-dependent PWM
+//|   signal.
+//|
+//|   :param ~microcontroller.Pin left_channel: The pin to output the left channel to
+//|   :param ~microcontroller.Pin right_channel: The pin to output the right channel to
+//|   :param int quiescent_value: The output value when no signal is present. Samples should start
+//|       and end with this value to prevent audible popping.
+//|
+//|   Simple 8ksps 440 Hz sin wave::
+//|
+//|     import audiocore
+//|     import audiopwmio
+//|     import board
+//|     import array
+//|     import time
+//|     import math
+//|
+//|     # Generate one period of sine wav.
+//|     length = 8000 // 440
+//|     sine_wave = array.array("H", [0] * length)
+//|     for i in range(length):
+//|         sine_wave[i] = int(math.sin(math.pi * 2 * i / 18) * (2 ** 15) + 2 ** 15)
+//|
+//|     dac = audiopwmio.PWMAudioOut(board.SPEAKER)
+//|     sine_wave = audiocore.RawSample(sine_wave, sample_rate=8000)
+//|     dac.play(sine_wave, loop=True)
+//|     time.sleep(1)
+//|     dac.stop()
+//|
+//|   Playing a wave file from flash::
+//|
+//|     import board
+//|     import audiocore
+//|     import audiopwmio
+//|     import digitalio
+//|
+//|     # Required for CircuitPlayground Express
+//|     speaker_enable = digitalio.DigitalInOut(board.SPEAKER_ENABLE)
+//|     speaker_enable.switch_to_output(value=True)
+//|
+//|     data = open("cplay-5.1-16bit-16khz.wav", "rb")
+//|     wav = audiocore.WaveFile(data)
+//|     a = audiopwmio.PWMAudioOut(board.SPEAKER)
+//|
+//|     print("playing")
+//|     a.play(wav)
+//|     while a.playing:
+//|       pass
+//|     print("stopped")
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_left_channel, ARG_right_channel, ARG_quiescent_value };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_left_channel, MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_right_channel, MP_ARG_OBJ | MP_ARG_KW_ONLY, {.u_rom_obj = mp_const_none} },
+        { MP_QSTR_quiescent_value, MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 0x8000} },
+    };
+    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+    mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+    mp_obj_t left_channel_obj = args[ARG_left_channel].u_obj;
+    assert_pin(left_channel_obj, false);
+    const mcu_pin_obj_t *left_channel_pin = MP_OBJ_TO_PTR(left_channel_obj);
+
+    mp_obj_t right_channel_obj = args[ARG_right_channel].u_obj;
+    const mcu_pin_obj_t *right_channel_pin = NULL;
+    if (right_channel_obj != mp_const_none) {
+        assert_pin(right_channel_obj, false);
+        right_channel_pin = MP_OBJ_TO_PTR(right_channel_obj);
+    }
+
+    // create AudioOut object from the given pin
+    audiopwmio_pwmaudioout_obj_t *self = m_new_obj(audiopwmio_pwmaudioout_obj_t);
+    self->base.type = &audiopwmio_pwmaudioout_type;
+    common_hal_audiopwmio_pwmaudioout_construct(self, left_channel_pin, right_channel_pin, args[ARG_quiescent_value].u_int);
+
+    return MP_OBJ_FROM_PTR(self);
+}
+
+//|   .. method:: deinit()
+//|
+//|      Deinitialises the PWMAudioOut and releases any hardware resources for reuse.
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_deinit(mp_obj_t self_in) {
+    audiopwmio_pwmaudioout_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    common_hal_audiopwmio_pwmaudioout_deinit(self);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(audiopwmio_pwmaudioout_deinit_obj, audiopwmio_pwmaudioout_deinit);
+
+STATIC void check_for_deinit(audiopwmio_pwmaudioout_obj_t *self) {
+    if (common_hal_audiopwmio_pwmaudioout_deinited(self)) {
+        raise_deinited_error();
+    }
+}
+//|   .. method:: __enter__()
+//|
+//|      No-op used by Context Managers.
+//|
+//  Provided by context manager helper.
+
+//|   .. method:: __exit__()
+//|
+//|      Automatically deinitializes the hardware when exiting a context. See
+//|      :ref:`lifetime-and-contextmanagers` for more info.
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_obj___exit__(size_t n_args, const mp_obj_t *args) {
+    (void)n_args;
+    common_hal_audiopwmio_pwmaudioout_deinit(args[0]);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(audiopwmio_pwmaudioout___exit___obj, 4, 4, audiopwmio_pwmaudioout_obj___exit__);
+
+
+//|   .. method:: play(sample, *, loop=False)
+//|
+//|     Plays the sample once when loop=False and continuously when loop=True.
+//|     Does not block. Use `playing` to block.
+//|
+//|     Sample must be an `audiocore.WaveFile`, `audiocore.RawSample`, or `audiocore.Mixer`.
+//|
+//|     The sample itself should consist of 16 bit samples. Microcontrollers with a lower output
+//|     resolution will use the highest order bits to output. For example, the SAMD21 has a 10 bit
+//|     DAC that ignores the lowest 6 bits when playing 16 bit samples.
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_obj_play(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_sample, ARG_loop };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_sample,    MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_loop,      MP_ARG_BOOL | MP_ARG_KW_ONLY, {.u_bool = false} },
+    };
+    audiopwmio_pwmaudioout_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
+    check_for_deinit(self);
+    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+    mp_obj_t sample = args[ARG_sample].u_obj;
+    common_hal_audiopwmio_pwmaudioout_play(self, sample, args[ARG_loop].u_bool);
+
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_KW(audiopwmio_pwmaudioout_play_obj, 1, audiopwmio_pwmaudioout_obj_play);
+
+//|   .. method:: stop()
+//|
+//|     Stops playback and resets to the start of the sample.
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_obj_stop(mp_obj_t self_in) {
+    audiopwmio_pwmaudioout_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    check_for_deinit(self);
+    common_hal_audiopwmio_pwmaudioout_stop(self);
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(audiopwmio_pwmaudioout_stop_obj, audiopwmio_pwmaudioout_obj_stop);
+
+//|   .. attribute:: playing
+//|
+//|     True when an audio sample is being output even if `paused`. (read-only)
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_obj_get_playing(mp_obj_t self_in) {
+    audiopwmio_pwmaudioout_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    check_for_deinit(self);
+    return mp_obj_new_bool(common_hal_audiopwmio_pwmaudioout_get_playing(self));
+}
+MP_DEFINE_CONST_FUN_OBJ_1(audiopwmio_pwmaudioout_get_playing_obj, audiopwmio_pwmaudioout_obj_get_playing);
+
+const mp_obj_property_t audiopwmio_pwmaudioout_playing_obj = {
+    .base.type = &mp_type_property,
+    .proxy = {(mp_obj_t)&audiopwmio_pwmaudioout_get_playing_obj,
+              (mp_obj_t)&mp_const_none_obj,
+              (mp_obj_t)&mp_const_none_obj},
+};
+
+//|   .. method:: pause()
+//|
+//|     Stops playback temporarily while remembering the position. Use `resume` to resume playback.
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_obj_pause(mp_obj_t self_in) {
+    audiopwmio_pwmaudioout_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    check_for_deinit(self);
+
+    if (!common_hal_audiopwmio_pwmaudioout_get_playing(self)) {
+        mp_raise_RuntimeError(translate("Not playing"));
+    }
+    common_hal_audiopwmio_pwmaudioout_pause(self);
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(audiopwmio_pwmaudioout_pause_obj, audiopwmio_pwmaudioout_obj_pause);
+
+//|   .. method:: resume()
+//|
+//|     Resumes sample playback after :py:func:`pause`.
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_obj_resume(mp_obj_t self_in) {
+    audiopwmio_pwmaudioout_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    check_for_deinit(self);
+
+    if (common_hal_audiopwmio_pwmaudioout_get_paused(self)) {
+        common_hal_audiopwmio_pwmaudioout_resume(self);
+    }
+
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(audiopwmio_pwmaudioout_resume_obj, audiopwmio_pwmaudioout_obj_resume);
+
+//|   .. attribute:: paused
+//|
+//|     True when playback is paused. (read-only)
+//|
+STATIC mp_obj_t audiopwmio_pwmaudioout_obj_get_paused(mp_obj_t self_in) {
+    audiopwmio_pwmaudioout_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    check_for_deinit(self);
+    return mp_obj_new_bool(common_hal_audiopwmio_pwmaudioout_get_paused(self));
+}
+MP_DEFINE_CONST_FUN_OBJ_1(audiopwmio_pwmaudioout_get_paused_obj, audiopwmio_pwmaudioout_obj_get_paused);
+
+const mp_obj_property_t audiopwmio_pwmaudioout_paused_obj = {
+    .base.type = &mp_type_property,
+    .proxy = {(mp_obj_t)&audiopwmio_pwmaudioout_get_paused_obj,
+              (mp_obj_t)&mp_const_none_obj,
+              (mp_obj_t)&mp_const_none_obj},
+};
+
+STATIC const mp_rom_map_elem_t audiopwmio_pwmaudioout_locals_dict_table[] = {
+    // Methods
+    { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&audiopwmio_pwmaudioout_deinit_obj) },
+    { MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) },
+    { MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&audiopwmio_pwmaudioout___exit___obj) },
+    { MP_ROM_QSTR(MP_QSTR_play), MP_ROM_PTR(&audiopwmio_pwmaudioout_play_obj) },
+    { MP_ROM_QSTR(MP_QSTR_stop), MP_ROM_PTR(&audiopwmio_pwmaudioout_stop_obj) },
+    { MP_ROM_QSTR(MP_QSTR_pause), MP_ROM_PTR(&audiopwmio_pwmaudioout_pause_obj) },
+    { MP_ROM_QSTR(MP_QSTR_resume), MP_ROM_PTR(&audiopwmio_pwmaudioout_resume_obj) },
+
+    // Properties
+    { MP_ROM_QSTR(MP_QSTR_playing), MP_ROM_PTR(&audiopwmio_pwmaudioout_playing_obj) },
+    { MP_ROM_QSTR(MP_QSTR_paused), MP_ROM_PTR(&audiopwmio_pwmaudioout_paused_obj) },
+};
+STATIC MP_DEFINE_CONST_DICT(audiopwmio_pwmaudioout_locals_dict, audiopwmio_pwmaudioout_locals_dict_table);
+
+const mp_obj_type_t audiopwmio_pwmaudioout_type = {
+    { &mp_type_type },
+    .name = MP_QSTR_PWMAudioOut,
+    .make_new = audiopwmio_pwmaudioout_make_new,
+    .locals_dict = (mp_obj_dict_t*)&audiopwmio_pwmaudioout_locals_dict,
+};
diff --git a/shared-bindings/audiopwmio/PWMAudioOut.h b/shared-bindings/audiopwmio/PWMAudioOut.h
new file mode 100644
index 000000000..22afc70d3
--- /dev/null
+++ b/shared-bindings/audiopwmio/PWMAudioOut.h
@@ -0,0 +1,49 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_SHARED_BINDINGS_AUDIOPWMIO_AUDIOOUT_H
+#define MICROPY_INCLUDED_SHARED_BINDINGS_AUDIOPWMIO_AUDIOOUT_H
+
+#include "common-hal/audiopwmio/PWMAudioOut.h"
+#include "common-hal/microcontroller/Pin.h"
+#include "shared-bindings/audiocore/RawSample.h"
+
+extern const mp_obj_type_t audiopwmio_pwmaudioout_type;
+
+// left_channel will always be non-NULL but right_channel may be for mono output.
+void common_hal_audiopwmio_pwmaudioout_construct(audiopwmio_pwmaudioout_obj_t* self,
+    const mcu_pin_obj_t* left_channel, const mcu_pin_obj_t* right_channel, uint16_t default_value);
+
+void common_hal_audiopwmio_pwmaudioout_deinit(audiopwmio_pwmaudioout_obj_t* self);
+bool common_hal_audiopwmio_pwmaudioout_deinited(audiopwmio_pwmaudioout_obj_t* self);
+void common_hal_audiopwmio_pwmaudioout_play(audiopwmio_pwmaudioout_obj_t* self, mp_obj_t sample, bool loop);
+void common_hal_audiopwmio_pwmaudioout_stop(audiopwmio_pwmaudioout_obj_t* self);
+bool common_hal_audiopwmio_pwmaudioout_get_playing(audiopwmio_pwmaudioout_obj_t* self);
+void common_hal_audiopwmio_pwmaudioout_pause(audiopwmio_pwmaudioout_obj_t* self);
+void common_hal_audiopwmio_pwmaudioout_resume(audiopwmio_pwmaudioout_obj_t* self);
+bool common_hal_audiopwmio_pwmaudioout_get_paused(audiopwmio_pwmaudioout_obj_t* self);
+
+#endif // MICROPY_INCLUDED_SHARED_BINDINGS_AUDIOPWMIO_AUDIOOUT_H
diff --git a/shared-bindings/audiopwmio/__init__.c b/shared-bindings/audiopwmio/__init__.c
new file mode 100644
index 000000000..8a2b202b3
--- /dev/null
+++ b/shared-bindings/audiopwmio/__init__.c
@@ -0,0 +1,71 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdint.h>
+
+#include "py/obj.h"
+#include "py/runtime.h"
+
+#include "shared-bindings/microcontroller/Pin.h"
+#include "shared-bindings/audiopwmio/__init__.h"
+#include "shared-bindings/audiopwmio/PWMAudioOut.h"
+
+//| :mod:`audiopwmio` --- Support for audio input and output
+//| ========================================================
+//|
+//| .. module:: audiopwmio
+//|   :synopsis: Support for audio output via digital PWM
+//|   :platform: NRF52
+//|
+//| The `audiopwmio` module contains classes to provide access to audio IO.
+//|
+//| Libraries
+//|
+//| .. toctree::
+//|     :maxdepth: 3
+//|
+//|     PWMAudioOut
+//|
+//| All classes change hardware state and should be deinitialized when they
+//| are no longer needed if the program continues after use. To do so, either
+//| call :py:meth:`!deinit` or use a context manager. See
+//| :ref:`lifetime-and-contextmanagers` for more info.
+//|
+//| Since CircuitPython 5, `Mixer`, `RawSample` and `WaveFile` are moved
+//| to :mod:`audiocore`.
+//|
+
+STATIC const mp_rom_map_elem_t audiopwmio_module_globals_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_audiopwmio) },
+    { MP_ROM_QSTR(MP_QSTR_PWMAudioOut), MP_ROM_PTR(&audiopwmio_pwmaudioout_type) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(audiopwmio_module_globals, audiopwmio_module_globals_table);
+
+const mp_obj_module_t audiopwmio_module = {
+    .base = { &mp_type_module },
+    .globals = (mp_obj_dict_t*)&audiopwmio_module_globals,
+};
diff --git a/shared-bindings/audiopwmio/__init__.h b/shared-bindings/audiopwmio/__init__.h
new file mode 100644
index 000000000..e4b7067d1
--- /dev/null
+++ b/shared-bindings/audiopwmio/__init__.h
@@ -0,0 +1,34 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_SHARED_BINDINGS_AUDIOIO___INIT___H
+#define MICROPY_INCLUDED_SHARED_BINDINGS_AUDIOIO___INIT___H
+
+#include "py/obj.h"
+
+// Nothing now.
+
+#endif  // MICROPY_INCLUDED_SHARED_BINDINGS_AUDIOIO___INIT___H