circuitpython/docs/library/machine.rst

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:mod:`machine` --- functions related to the board
=================================================
.. module:: machine
:synopsis: functions related to the board
The ``machine`` module contains specific functions related to the board.
Reset related functions
-----------------------
.. function:: reset()
Resets the device in a manner similar to pushing the external RESET
button.
.. function:: reset_cause()
Get the reset cause. See :ref:`constants <machine_constants>` for the possible return values.
Interrupt related functions
---------------------------
.. function:: disable_irq()
Disable interrupt requests.
Returns the previous IRQ state: ``False``/``True`` for disabled/enabled IRQs
respectively. This return value can be passed to enable_irq to restore
the IRQ to its original state.
.. function:: enable_irq(state=True)
Enable interrupt requests.
If ``state`` is ``True`` (the default value) then IRQs are enabled.
If ``state`` is ``False`` then IRQs are disabled. The most common use of
this function is to pass it the value returned by ``disable_irq`` to
exit a critical section.
Power related functions
-----------------------
.. function:: freq()
.. only:: not port_wipy
Returns CPU frequency in hertz.
.. only:: port_wipy
Returns a tuple of clock frequencies: ``(sysclk,)``
These correspond to:
- sysclk: frequency of the CPU
.. function:: idle()
Gates the clock to the CPU, useful to reduce power consumption at any time during
short or long periods. Peripherals continue working and execution resumes as soon
as any interrupt is triggered (including the systick which has a period of 1ms).
Current consumption is reduced to ~12mA (in WLAN STA mode)
.. function:: sleep()
Stops the CPU and disables all peripherals except for WLAN. Execution is resumed from
the point where the sleep was requested. Wake sources are ``Pin``, ``RTC`` and ``WLAN``.
Current consumption is reduced to 950uA (in WLAN STA mode).
.. function:: deepsleep()
Stops the CPU and all peripherals including WLAN. Execution is resumed from main, just
as with a reset. The reset cause can be checked to know that we are coming from
from ``machine.DEEPSLEEP``. Wake sources are ``Pin`` and ``RTC``. Current consumption
is reduced to ~5uA.
.. function:: wake_reason()
Get the wake reason. See :ref:`constants <machine_constants>` for the possible return values.
Miscellaneous functions
-----------------------
.. function:: main(filename)
Set the filename of the main script to run after boot.py is finished. If
this function is not called then the default file main.py will be executed.
It only makes sense to call this function from within boot.py.
.. function:: rng()
Return a 24-bit software generated random number.
.. function:: unique_id()
Returns a string of 6 bytes (48 bits), which is the unique ID of the MCU.
This also corresponds to the network ``MAC address``.
.. _machine_constants:
Constants
---------
.. data:: machine.IDLE
.. data:: machine.SLEEP
.. data:: machine.DEEPSLEEP
irq wake values
.. data:: machine.POWER_ON
.. data:: machine.HARD_RESET
.. data:: machine.WDT_RESET
.. data:: machine.DEEPSLEEP_RESET
.. data:: machine.SOFT_RESET
reset causes
.. data:: machine.WLAN_WAKE
.. data:: machine.PIN_WAKE
.. data:: machine.RTC_WAKE
wake reasons
Classes
-------
.. toctree::
:maxdepth: 1
machine.ADC.rst
machine.I2C.rst
machine.Pin.rst
machine.RTC.rst
machine.SD.rst
machine.SPI.rst
machine.Timer.rst
machine.UART.rst
machine.WDT.rst