2015-10-14 11:32:01 +01:00
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.. _machine.WDT:
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2015-06-10 22:29:56 +01:00
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class WDT -- watchdog timer
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===========================
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The WDT is used to restart the system when the application crashes and ends
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up into a non recoverable state. Once started it cannot be stopped or
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2015-10-14 11:32:01 +01:00
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reconfigured in any way. After enabling, the application must "feed" the
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2015-06-10 22:29:56 +01:00
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watchdog periodically to prevent it from expiring and resetting the system.
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Example usage::
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2015-10-14 11:32:01 +01:00
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wdt = machine.WDT(timeout=2000) # enable with a timeout of 2s
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2015-09-13 16:06:12 +01:00
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wdt.feed()
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2015-06-10 22:29:56 +01:00
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Constructors
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------------
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2015-10-14 11:32:01 +01:00
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.. class:: machine.WDT(id=0, timeout=5000)
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2015-06-10 22:29:56 +01:00
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2015-09-13 16:06:12 +01:00
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Create a WDT object and start it. The timeout must be given in seconds and
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the minimum value that is accepted is 1 second. Once it is running the timeout
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cannot be changed and the WDT cannot be stopped either.
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2015-06-10 22:29:56 +01:00
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Methods
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-------
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2015-09-13 16:06:12 +01:00
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.. method:: wdt.feed()
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2015-06-10 22:29:56 +01:00
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2015-09-13 16:06:12 +01:00
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Feed the WDT to prevent it from resetting the system. The application
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2015-06-10 22:29:56 +01:00
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should place this call in a sensible place ensuring that the WDT is
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2015-09-13 16:06:12 +01:00
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only fed after verifying that everything is functioning correctly.
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