circuitpython/docs/library/index.rst

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.. _micropython_lib:
MicroPython libraries
=====================
.. warning::
Important summary of this section
* MicroPython provides built-in modules that mirror the functionality of the
Python standard library (e.g. :mod:`os`, :mod:`time`), as well as
MicroPython-specific modules (e.g. :mod:`bluetooth`, :mod:`machine`).
* Most standard library modules implement a subset of the functionality of
the equivalent Python module, and in a few cases provide some
MicroPython-specific extensions (e.g. :mod:`array`, :mod:`os`)
* Due to resource constraints or other limitations, some ports or firmware
versions may not include all the functionality documented here.
* To allow for extensibility, the built-in modules can be extended from
Python code loaded onto the device.
This chapter describes modules (function and class libraries) which are built
into MicroPython. This documentation in general aspires to describe all modules
and functions/classes which are implemented in the MicroPython project.
However, MicroPython is highly configurable, and each port to a particular
board/embedded system may include only a subset of the available MicroPython
libraries.
With that in mind, please be warned that some functions/classes in a module (or
even the entire module) described in this documentation **may be unavailable**
in a particular build of MicroPython on a particular system. The best place to
find general information of the availability/non-availability of a particular
feature is the "General Information" section which contains information
pertaining to a specific :term:`MicroPython port`.
On some ports you are able to discover the available, built-in libraries that
can be imported by entering the following at the :term:`REPL`::
help('modules')
Beyond the built-in libraries described in this documentation, many more
modules from the Python standard library, as well as further MicroPython
extensions to it, can be found in :term:`micropython-lib`.
Python standard libraries and micro-libraries
---------------------------------------------
The following standard Python libraries have been "micro-ified" to fit in with
the philosophy of MicroPython. They provide the core functionality of that
module and are intended to be a drop-in replacement for the standard Python
library.
.. toctree::
:maxdepth: 1
array.rst
binascii.rst
builtins.rst
cmath.rst
collections.rst
errno.rst
gc.rst
hashlib.rst
heapq.rst
io.rst
json.rst
math.rst
os.rst
random.rst
re.rst
select.rst
socket.rst
ssl.rst
struct.rst
sys.rst
time.rst
uasyncio.rst
zlib.rst
_thread.rst
MicroPython-specific libraries
------------------------------
Functionality specific to the MicroPython implementation is available in
the following libraries.
.. toctree::
:maxdepth: 1
bluetooth.rst
btree.rst
cryptolib.rst
framebuf.rst
machine.rst
micropython.rst
neopixel.rst
network.rst
uctypes.rst
The following libraries provide drivers for hardware components.
.. toctree::
:maxdepth: 1
wm8960.rst
Port-specific libraries
-----------------------
In some cases the following port/board-specific libraries have functions or
classes similar to those in the :mod:`machine` library. Where this occurs, the
entry in the port specific library exposes hardware functionality unique to
that platform.
To write portable code use functions and classes from the :mod:`machine` module.
To access platform-specific hardware use the appropriate library, e.g.
:mod:`pyb` in the case of the Pyboard.
Libraries specific to the pyboard
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following libraries are specific to the pyboard.
.. toctree::
:maxdepth: 2
pyb.rst
stm.rst
lcd160cr.rst
Libraries specific to the WiPy
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following libraries and classes are specific to the WiPy.
.. toctree::
:maxdepth: 2
wipy.rst
machine.ADCWiPy.rst
machine.TimerWiPy.rst
Libraries specific to the ESP8266 and ESP32
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following libraries are specific to the ESP8266 and ESP32.
.. toctree::
:maxdepth: 2
esp.rst
esp32.rst
Libraries specific to the RP2040
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following libraries are specific to the RP2040, as used in the Raspberry Pi Pico.
.. toctree::
:maxdepth: 2
rp2.rst
Libraries specific to Zephyr
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following libraries are specific to the Zephyr port.
.. toctree::
:maxdepth: 2
zephyr.rst
Extending built-in libraries from Python
----------------------------------------
In most cases, the above modules are actually named ``umodule`` rather than
``module``, but MicroPython will alias any module prefixed with a ``u`` to the
non-``u`` version. However a file (or :term:`frozen module`) named
``module.py`` will take precedence over this alias.
This allows the user to provide an extended implementation of a built-in library
(perhaps to provide additional CPython compatibility). The user-provided module
(in ``module.py``) can still use the built-in functionality by importing
``umodule`` directly. This is used extensively in :term:`micropython-lib`. See
:ref:`packages` for more information.
This applies to both the Python standard libraries (e.g. ``os``, ``time``, etc),
but also the MicroPython libraries too (e.g. ``machine``, ``bluetooth``, etc).
The main exception is the port-specific libraries (``pyb``, ``esp``, etc).
*Other than when you specifically want to force the use of the built-in module,
we recommend always using* ``import module`` *rather than* ``import umodule``.