7.1 KiB
MicroPython libraries
Warning
Important summary of this section
- MicroPython provides built-in modules that mirror the functionality
of the
Python standard library <micropython_lib_python>
(e.g.os
,time
), as well asMicroPython-specific modules <micropython_lib_micropython>
(e.g.bluetooth
,machine
). - Most Python 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.
array
,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, some built-in modules can be
extended from Python code <micropython_lib_extending>
loaded onto the device filesystem.
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 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 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 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.
array.rst asyncio.rst binascii.rst builtins.rst cmath.rst collections.rst errno.rst gc.rst gzip.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 zlib.rst _thread.rst
MicroPython-specific libraries
Functionality specific to the MicroPython implementation is available in the following libraries.
bluetooth.rst btree.rst cryptolib.rst deflate.rst framebuf.rst machine.rst micropython.rst neopixel.rst network.rst uctypes.rst
The following libraries provide drivers for hardware components.
wm8960.rst
Port-specific libraries
In some cases the following port/board-specific libraries have
functions or classes similar to those in the 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 machine
module. To access
platform-specific hardware use the appropriate library, e.g. pyb
in the case of the
Pyboard.
Libraries specific to the pyboard
The following libraries are specific to the pyboard.
pyb.rst stm.rst lcd160cr.rst
Libraries specific to the WiPy
The following libraries and classes are specific to the WiPy.
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.
esp.rst esp32.rst
espnow.rst
Libraries specific to the RP2040
The following libraries are specific to the RP2040, as used in the Raspberry Pi Pico.
rp2.rst
Libraries specific to Zephyr
The following libraries are specific to the Zephyr port.
zephyr.rst
Extending built-in libraries from Python
A subset of the built-in modules are able to be extended by Python
code by providing a module of the same name in the filesystem. This
extensibility applies to the following Python standard library modules
which are built-in to the firmware: array
,
binascii
, collections
, errno
,
gzip
, hashlib
, heapq
,
io
, json
, os
,
platform
, random
, re
,
select
, socket
, ssl
,
struct
, time
zlib
, as well as the
MicroPython-specific machine
module. All other built-in
modules cannot be extended from the filesystem.
This allows the user to provide an extended implementation of a
built-in library (perhaps to provide additional CPython compatibility or
missing functionality). This is used extensively in micropython-lib
, see packages
for more
information. The filesystem module will typically do a wildcard import
of the built-in module in order to inherit all the globals (classes,
functions and variables) from the built-in.
In MicroPython v1.21.0 and higher, to prevent the filesystem module
from importing itself, it can force an import of the built-in module it
by temporarily clearing sys.path
during the import. For
example, to extend the time
module from Python, a file
named time.py
on the filesystem would do the following:
_path = sys.path
sys.path = ()
try:
from time import *
finally:
sys.path = _path
del _path
def extra_method():
pass
The result is that time.py
contains all the globals of
the built-in time
module, but adds
extra_method
.
In earlier versions of MicroPython, you can force an import of a
built-in module by appending a u
to the start of its name.
For example, import utime
instead of
import time
. For example, time.py
on the
filesystem could look like:
from utime import *
def extra_method():
pass
This way is still supported, but the sys.path
method
described above is now preferred as the u
-prefix will be
removed from the names of built-in modules in a future version of
MicroPython.
Other than when it specifically needs to force the use of the
built-in module, code should always use import module
rather than import umodule
.