Source code for soundboard

"""
This is a MicroPython library for the Adafruit Sound Boards in UART mode!

This library has been adapted from the library written by Adafruit for Arduino,
available at https://github.com/adafruit/Adafruit_Soundboard_library. I have no
affiliation with Adafruit, and they have not sponsored or approved this library
in any way. As such, please do not contact them for support regarding this
library.

Commands the sound board understands (at least the ones I could discern from
the Arduino library) are as follows:

- ``L``: List files on the board
- ``#``: Play a file by number
- ``P``: Play a file by name
- ``+``: Volume up. Range is 0-204, increments of 2.
- ``-``: Volume down
- ``=``: Pause playback
- ``>``: Un-pause playback
- ``q``: Stop playback
- ``t``: Give current position of playback and total time of track
- ``s``: Current track size and total size
"""

from machine import UART, Pin
from sys import platform as BOARD

__author__ = 'Mike Mabey'
__license__ = 'MIT'
__copyright_ = 'Copyright 2017, Mike Mabey'

ESP8266 = 'esp8266'
PYBOARD = 'pyboard'
WIPY = 'wipy'

try:
    # Should be supported by all 3 supported boards
    from utime import sleep_ms
except ImportError:
    _supported = ', '.join([ESP8266, PYBOARD, WIPY])
    raise OSError('Unsupported board. Currently only works with {}.'.format(_supported))

SB_BAUD = 9600  # Baud rate of the sound boards
MIN_VOL = 0
MAX_VOL = 204
MAX_FILES = 25
DEBUG = False


[docs]class Soundboard: """Control an Adafruit Sound Board via UART. The :class:`Soundboard` class handles all communication with the sound board via :ref:`UART <upy:machine.UART>`, making it easy to get information about the sound files on the sound board and control playback. If you need to reset the sound board from your MicroPython code, be sure to provide the ``rst_pin`` parameter. The soundboard sometimes gets out of UART mode and reverts to the factory default of GPIO trigger mode. When this happens, it will appear as if the soundboard has stoped working for no apparent reason. This library is designed to automatically attempt resetting the board if a command fails, since that is a common cause. So, it is a good idea to provide this parameter. """ def __init__(self, uart_id, rst_pin=None, vol=None, alt_get_files=False, debug=None, **uart_kwargs): """ :param uart_id: ID for the :ref:`UART <upy:machine.UART>` bus to use. Acceptable values vary by board. Check the documentation for your board for more info. :param rst_pin: Identifier for the pin (on the MicroPython board) connected to the ``RST`` pin of the sound board. Valid identifiers vary by board. :param vol: Initial volume level to set. See :attr:`vol` for more info. :type vol: int or float :param bool alt_get_files: Uses an alternate method to get the list of track file names. See :meth:`use_alt_get_files` method for more info. :param bool debug: When not None, will set the debug output flag to the boolean value of this argument using the :meth:`toggle_debug` method. :param dict uart_kwargs: Additional values passed to the :ref:`UART.init() <upy:machine.UART>` method of the UART bus object. Acceptable values here also vary by board. It is not necessary to include the baud rate among these keyword values, because it will be set to ``SB_BAUD`` before the ``UART.init`` function is called. """ if debug is not None: self.toggle_debug(bool(debug)) self._uart = UART(uart_id, SB_BAUD) uart_kwargs['baudrate'] = SB_BAUD self._uart.init(**uart_kwargs) self._files = None self._sizes = None self._lengths = None self._track = {} self._cur_vol = None self._cur_track = None self._reset_attempted = False # Setup reset pin if BOARD == PYBOARD: self._sb_rst = None if rst_pin is None else Pin(rst_pin, mode=Pin.OPEN_DRAIN, value=1) else: self._sb_rst = None if rst_pin is None else Pin(rst_pin, mode=Pin.IN) self.vol = vol if alt_get_files: self.use_alt_get_files() # Get the track lengths (also retrieves the list of files) TODO # print('Getting track lengths. This will take a couple seconds.') # self._get_lengths() def _flush_uart_input(self): """Read any available data from the UART bus until none is left.""" while self._uart.any(): self._uart.read() def _send_simple(self, cmd, check=None, strip=True): """Send the command, optionally do a check on the output. :param cmd: Command to send over the UART bus. A newline character will be appended to the command before sending it, so it's not necessary to include one as part of the command. :type cmd: str or bytes :param check: Depending on the type of `check`, has three different behaviors. When None (default), the return value will be whatever the output from the command was. When a str or bytes, the return value will be True/False, indicating whether the command output starts with the value in `check`. When it otherwise evaluates to True, return value will be True/False, indicating the output started with the first character in `cmd`. :type check: str or bytes or None or bool :return: Varies depending on the value of `check`. :rtype: bytes or bool """ self._flush_uart_input() cmd = cmd.strip() # Make sure there's not more than one newline self._uart.write('{}\n'.format(cmd)) if len(cmd) > 1: # We need to gobble the return when there's more than one character in the command self._uart.readline() try: msg = self._uart.readline() if strip: msg = msg.strip() assert isinstance(msg, bytes) printif(msg) except (AttributeError, AssertionError): if self._reset_attempted: # Only try resetting once return False # TODO: Better way to handle failed commands? Too broad? printif('Got back None from a command. Attempting to restart the board to put it in UART mode.') self._reset_attempted = True self.reset() return self._send_simple(cmd, check) if check is None: return msg else: self._reset_attempted = True # We already sent a command successfully if isinstance(check, str): return msg.startswith(check.encode()) elif isinstance(check, bytes): return msg.startswith(check) elif check: return msg.startswith(cmd[0].encode()) @property def files(self): """Return a ``list`` of the files on the sound board. :rtype: list """ if self._files is None: self._get_files() return self._files @property def sizes(self): """Return a ``list`` of the files' sizes on the sound board. .. seealso:: :meth:`use_alt_get_files` :rtype: list """ if self._sizes is None: self._get_files() return self._sizes def _get_files(self): """Ask the board for the files and their sizes, store the results.""" self._flush_uart_input() self._files = [] self._sizes = [] self._uart.write('L\n') sleep_ms(10) i = 0 while self._uart.any(): msg = self._uart.readline().strip() printif(msg) fname, fsize = msg.split(b'\t') fname = fname.decode() self._files.append(fname) self._sizes.append(int(fsize)) self._track[fname] = i i += 1 def _get_files_alt(self): """Play every track, get info from feedback.""" vol = self.vol self.vol = 0 self._files = [] self._lengths = [] self._sizes = [] for i in range(MAX_FILES): self.stop() msg = self._send_simple('#{}'.format(i)) if msg.startswith(b'NoFile'): # Playing track i failed, it must not be a valid track number break play, track_num, fname = msg.split(b'\t') self._files.append(fname) self._track[fname] = i sleep_ms(50) sec = self.track_time() if sec: self._lengths.append(sec[1]) else: self._lengths.append(0) size = self.track_size() if size: self._sizes.append(size[1]) else: self._sizes.append(0) self.vol = vol @property def lengths(self): """Return a ``list`` of the track lengths in seconds. .. note:: In my own testing of this method, the board always returns a value of zero seconds for the length for every track, no matter if it's a WAV or OGG file, short or long track. :rtype: list """ if self._lengths is None: self._get_lengths() return self._lengths def _get_lengths(self): """Store the length of each track.""" self._get_files_alt()
[docs] def file_name(self, n): """Return the name of track ``n``. :param int n: Index of a file on the sound board or ``False`` if the track number doesn't exist. :return: Filename of track ``n``. :rtype: str or bool """ try: return self.files[n] except IndexError: return False
[docs] def track_num(self, file_name): """Return the track number of the given file name. :param str file_name: File name of the track. Should be one of the values from the :attr:`files` property. :return: The track number of the file name or ``False`` if not found. :rtype: int or bool """ try: return self._track[file_name] except KeyError: return False
[docs] def play(self, track=None): """Play a track on the board. :param track: The index (``int``) or filename (``str``) of the track to play. :type track: int or str :return: If the command was successful. :rtype: bool """ if isinstance(track, int): cmd = '#' num = track elif isinstance(track, str): cmd = 'P' num = self.track_num(track) else: raise TypeError('You must specify a track by its number (int) or its name (str)') if self._send_simple('{}{}'.format(cmd, track), 'play'): self._cur_track = num return True return False
[docs] def play_now(self, track): """Play a track on the board now, stopping current track if necessary. :param track: The index (``int``) or filename (``str``) of the track to play. :type track: int or str :return: If the command was successful. :rtype: bool """ self.stop() if not self.play(track): # Playing the specified track failed, so just return False return False return True
@property def vol(self): """Current volume. This is implemented as a class property, so you can get and set its value directly. When setting a new volume, you can use an ``int`` or a ``float`` (assuming your board supports floats). When setting to an ``int``, it should be in the range of 0-204. When set to a ``float``, the value will be interpreted as a percentage of :obj:`MAX_VOL`. :rtype: int """ if self._cur_vol is None: self.vol_down() return self._cur_vol @vol.setter def vol(self, new_vol): if new_vol is None: return if isinstance(new_vol, float): new_vol = int(new_vol * MAX_VOL) if not isinstance(new_vol, int): printif('Invalid volume level. Try giving an int.') return elif new_vol > self.vol: self.vol_up(new_vol) elif new_vol < self.vol: self.vol_down(new_vol)
[docs] def vol_up(self, vol=None): """Turn volume up by 2 points, return current volume level [0-204]. :param int vol: Target volume. When not ``None``, volume will be turned up to be greater than or equal to this value. :rtype: int """ global DEBUG printif('Turning volume up') if vol is None: self._cur_vol = int(self._send_simple('+')) return self._cur_vol if vol > MAX_VOL: printif('{} is above maximum volume. Setting to {} instead.'.format(vol, MAX_VOL)) vol = MAX_VOL self._cur_vol = MIN_VOL - 1 db = DEBUG DEBUG = False while vol > self._cur_vol: self._cur_vol = int(self._send_simple('+')) DEBUG = db return self._cur_vol
[docs] def vol_down(self, vol=None): """Turn volume down by 2 points, return current volume level [0-204]. :param int vol: Target volume. When not ``None``, volume will be turned down to be less than or equal to this value. :rtype: int """ global DEBUG printif('Turning volume down') if vol is None: self._cur_vol = int(self._send_simple('-')) return self._cur_vol self._cur_vol = MAX_VOL + 1 if vol < MIN_VOL: printif('{} is below minimum volume. Setting to {} instead.'.format(vol, MIN_VOL)) vol = MIN_VOL db = DEBUG DEBUG = False while vol < self._cur_vol: self._cur_vol = int(self._send_simple('-')) DEBUG = db return self._cur_vol
[docs] def pause(self): """Pause playback, return if the command was successful. :rtype: bool """ return self._send_simple('=', True)
[docs] def unpause(self): """Continue playback, return if the command was successful. :rtype: bool """ return self._send_simple('>', True)
[docs] def stop(self): """Stop playback, return if the command was successful. :rtype: bool """ return self._send_simple('q', True)
[docs] def track_time(self): """Return the current position of playback and total time of track. :rtype: tuple """ msg = self._send_simple('t') if not msg: return -1, -1 printif(len(msg)) if len(msg) != 11: return False current, total = msg.decode('utf-8').split(':') return int(current), int(total)
[docs] def track_size(self): """Return the remaining size and total size. It seems the remaining track size refers to the number of bytes left for the soundboard to process before the playing of the track will be over. :return: Remaining track size and total size :rtype: tuple """ msg = self._send_simple('s') if not msg: return -1, -1 printif(len(msg)) if len(msg) != 21: return False remaining, total = msg.decode('utf-8').split('/') return int(remaining), int(total)
[docs] def reset(self): """Reset the sound board. Soft reset the board by bringing the ``RST`` pin low momentarily (10 ms). This only has effect if the reset pin has been initialized in the constructor. Doing a soft reset on the board before doing any other actions can help ensure that it has been started in UART control mode, rather than GPIO trigger mode. .. seealso:: `Soundboard Pinout <https://learn.adafruit.com/adafruit-audio-fx-sound-board/pinouts#uart-pins>`_ Documentation on the soundboards' pinouts. :return: Whether the reset was successful. If the reset pin was not initialized in the constructor, this will always return ``False``. :rtype: bool """ if self._sb_rst is None: # Don't attempt to restart the board if the reset pin wasn't initialized return False if BOARD == PYBOARD: self._sb_rst(0) sleep_ms(10) self._sb_rst(1) else: # Pin should already be in IN mode. This allows us to set the value we want to send, then switch to OUT mode # just long enough for the value to take effect, and finally switch back to IN mode. # self._sb_rst.value(0) self._sb_rst(0) self._sb_rst.mode(Pin.OUT) sleep_ms(10) self._sb_rst.mode(Pin.IN) sleep_ms(1000) # Give the board some time to boot msg = self._uart.readline().strip() printif(msg) # Date and name msg = self._uart.readline().strip() printif('Document what this line is: >{}<'.format(msg)) # ? # TODO if not msg.startswith('Adafruit FX Sound Board'): return False sleep_ms(250) msg = self._uart.readline().strip() printif(msg) # FAT type msg = self._uart.readline().strip() printif(msg) # Number of files # Reset volume level and current track self.vol = self._cur_vol self._cur_track = None return True
[docs] def use_alt_get_files(self, now=False): """Get list of track files using an alternate method. If the list of files is missing tracks you know are on the soundboard, try calling this method. It doesn't depend on the soundboard's internal command for returning a list of files. Instead, it plays each of the tracks using their track numbers and gets the filename and size from the output of the play command. :param bool now: When set to ``True``, the alternate method of getting the files list will be called immediately. Otherwise, the list of files will be populated the next time the :attr:`files` property is accessed (lazy loading). :rtype: None """ self._get_files = self._get_files_alt if now: self._get_files()
@staticmethod
[docs] def toggle_debug(debug=None): """Turn on/off :obj:`DEBUG` flag. :param debug: If None, the :obj:`DEBUG` flag will be toggled to have the value opposite of its current value. Otherwise, :obj:`DEBUG` will be set to the boolean value of ``debug``. :rtype: None """ global DEBUG if debug is None: DEBUG = not DEBUG else: DEBUG = bool(debug)
[docs]def printif(*values, **kwargs): """Print a message if :obj:`DEBUG` is set to ``True``.""" print(*values, **kwargs) if DEBUG else None