This driver is used to control a WM8960 codec chip. It is a Python translation of the C-Code provided by NXP/Freescale for their i.MX RT series of MCUs. Very little has been added, and just a few API related names were changed or added to cope with the naming style of MicroPython.

The primary purpose of the driver is initialization and setting operation modes of the codec. It does not do the audio data processing for the codec. That is the task of a separate driver.

The WM8960 supports an I2C interface, in addition to the audio interface. The connection depends on the interface used and the number of devices in the system. For the I2C interface, SCL and SDA have to be connected, and of course GND and Vcc. The I2C default address is 0x1A.

In addition to initialization, the driver provides some useful methods for controlling its operation:

.. method:: WM8960.set_left_input(input_source)

    Specify the source for the left input.  The input source names are listed above.

.. method:: WM8960.set_right_input(input_source)

    Specify the source for the right input.  The input source names are listed above.

.. method:: WM8960.volume(module, volume_l=None, volume_r=None)

    Sets or gets the volume of a certain module.

    If no volume values are supplied, the actual volume tuple is returned.

    If one or two values are supplied, it sets the volume of a certain module.
    If two values are provided, the first one is used for the left channel,
    the second for the right channel.  If only one value is supplied, it is used
    for both channels.  The value range is normalized to 0.0-100.0 with a
    logarithmic scale.

    For a list of suitable modules and db/step, see the table below.

.. method:: WM8960.mute(module, mute, soft=True, ramp=wm8960.MUTE_FAST)

    Mute or unmute the output. If *mute* is True, the output is muted, if ``False``
    it is unmuted.

    If *soft* is set as True, muting will happen as a soft transition.  The time for
    the transition is defined by *ramp*, which is either ``MUTE_FAST`` or ``MUTE_SLOW``.

.. method:: WM8960.set_data_route(route)

    Set the audio data route.  For the parameter value/names, see the table above.

.. method:: WM8960.set_module(module, active)

    Enable or disable a module, with *active* being ``False`` or ``True``.  For
    the list of module names, see the table above.

    Note that enabling ``MODULE_MONO_OUT`` is different from the `WM8960.mono`
    method.  The first enables output 3, while the `WM8960.mono` method sends a
    mono mix to the left and right output.

.. method:: WM8960.enable_module(module)

    Enable a module.  For the list of module names, see the table above.

.. method:: WM8960.disable_module(module)

    Disable a module.  For the list of module names, see the table above.

.. method:: WM8960.expand_3d(level)

    Enable Stereo 3D exansion.  *level* is a number between 0 and 15.
    A value of 0 disables the expansion.

.. method:: WM8960.mono(active)

    If *active* is ``True``, a Mono mix is sent to the left and right output
    channel.  This is different from enabling the ``MODULE_MONO_MIX``, which
    enables output 3.

.. method:: WM8960.alc_mode(channel, mode=ALC_MODE)

    Enables or disables ALC mode.  Parameters are:

    - *channel* enables and sets the channel for ALC. The parameter values are:

        - ALC_OFF:   Switch ALC off
        - ALS_RIGHT:  Use the right input channel
        - ALC_LEFT:   Use the left input channel
        - ALC_STEREO: Use both input channels.

    - *mode* sets the ALC mode. Input values are:

        - ALC_MODE:   act as ALC
        - ALC_LIMITER: act as limiter.

.. method:: WM8960.alc_gain(target=-12, max_gain=30, min_gain=-17.25, noise_gate=-78)

    Set the target level, highest and lowest gain levels and the noise gate as dB level.
    Permitted ranges are:

    - *target*: -22.5 to -1.5 dB
    - *max_gain*: -12 to 30 dB
    - *min_gain*: -17 to 25 dB
    - *noise_gate*: -78 to -30 dB

    Excess values are limited to the permitted ranges.  A value of -78 or less
    for *noise_gate* disables the noise gate function.

.. method:: WM8960.alc_time(attack=24, decay=192, hold=0)

    Set the dynamic characteristic of ALC.  The times are given as millisecond
    values.  Permitted ranges are:

    - *attack*: 6 to 6140
    - *decay*: 24 to 24580
    - *hold*: 0 to 43000

    Excess values are limited within the permitted ranges.

.. method:: WM8960.deemphasis(active)

    Enables or disables a deemphasis filter for playback, with *active* being
    ``False`` or ``True``.  This filter is applied only for sample rates of
    32000, 44100 and 48000.  For other sample rates, the filter setting
    is silently ignored.

.. method:: WM8960.deinit()

    Disable all modules.

Run WM8960 in secondary mode (default):

# Micro_python WM8960 Codec driver
#
# Setting the driver to Slave mode using the default settings
#
from machine import Pin, I2C
import wm8960
i2c = I2C(0)
wm=wm8960.WM8960(i2c, 32000, left_input=wm8960.INPUT_MIC1)
wm.set_volume(wm8960.MODULE_HEADPHONE, 100)

Run WM8960 in primary mode:

# Micro_python WM8960 Codec driver
#
# Setting the driver to Master mode using specific audio format settings
#
from machine import Pin, I2C
import wm8960

i2c = I2C(0)
wm=wm8960.WM8960(i2c, 44100, primary=True, bits=16)

Run WM8960 on a MIMXRT10xx_DEV board in secondary mode (default):

# Micro_python WM8960 Codec driver
#
# Setting the driver to Slave mode using the default settings
# swap the input channels such that a MIMXRT Dev board mic, which
# is connected to the right input, is assigned to the left audio channel.
#
from machine import Pin, I2C
import wm8960
i2c = I2C(0)
wm=wm8960.WM8960(i2c, sample_rate=16_000,
    adc_sync=wm8960.SYNC_DAC,
    swap=wm8960.SWAP_INPUT,
    sysclk_source=wm8960.SYSCLK_MCLK)

Record with a Sparkfun WM8960 breakout board with Teensy in secondary mode (default):

# Micro_python WM8960 Codec driver
#
# The breakout board uses a fixed 24MHz MCLK. Therefore the internal
# PLL must be used as sysclk, which is the master audio clock.
# The Sparkfun board has the WS pins for RX and TX connected on the
# board. Therefore adc_sync must be set to sync_adc, to configure
# it's ADCLRC pin as input.
#
from machine import Pin, I2C
import wm8960
i2c = I2C(0)
wm=wm8960.WM8960(i2c, sample_rate=16_000,
    adc_sync=wm8960.SYNC_ADC,
    sysclk_source=wm8960.SYSCLK_PLL,
    mclk_freq=24_000_000,
    left_input=wm8960.INPUT_MIC1,
    right_input=wm8960.INPUT_CLOSED)

Play with a Sparkfun WM8960 breakout board with Teensy in secondary mode (default):

# The breakout board uses a fixed 24MHz MCLK. Therefore the internal
# PLL must be used as sysclk, which is the master audio clock.
# The Sparkfun board has the WS pins for RX and TX connected on the
# board. Therefore adc_sync must be set to sync_adc, to configure
# it's ADCLRC pin as input.

from machine import I2C
i2c=I2C(0)
import wm8960
wm=wm8960.WM8960(i2c, sample_rate=44_100,
    adc_sync=wm8960.SYNC_ADC,
    sysclk_source=wm8960.SYSCLK_PLL,
    mclk_freq=24_000_000)
wm.set_volume(wm8960.MODULE_HEADPHONE, 100)