circuitpython/docs/library/machine.WDT.rst
Paul Sokolovsky c8b7628094 docs/machine.*: Add "currentmodule:: machine" directive.
Makes sure that classes described in these separate files are properly
designated as belonging to "machine" module in indexes.
2016-06-08 00:46:27 +03:00

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.. currentmodule:: machine
.. _machine.WDT:
class WDT -- watchdog timer
===========================
The WDT is used to restart the system when the application crashes and ends
up into a non recoverable state. Once started it cannot be stopped or
reconfigured in any way. After enabling, the application must "feed" the
watchdog periodically to prevent it from expiring and resetting the system.
Example usage::
from machine import WDT
wdt = WDT(timeout=2000) # enable it with a timeout of 2s
wdt.feed()
Constructors
------------
.. class:: machine.WDT(id=0, timeout=5000)
Create a WDT object and start it. The timeout must be given in seconds and
the minimum value that is accepted is 1 second. Once it is running the timeout
cannot be changed and the WDT cannot be stopped either.
Methods
-------
.. method:: wdt.feed()
Feed the WDT to prevent it from resetting the system. The application
should place this call in a sensible place ensuring that the WDT is
only fed after verifying that everything is functioning correctly.