36 lines
1.6 KiB
ReStructuredText
36 lines
1.6 KiB
ReStructuredText
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``timer_gpio``
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==============
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This example uses the timer interrupt to periodically change the state of a
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digital output. The digital output may be a relay, a led or anything else.
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This example can be very useful to validate timer drivers by using a logic
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analyzer connected to the digital output. This example mainly differs from
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the timer example because it waits on a sigwaitinfo() instead of using a
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signal handler. This approach ensures a deterministic wake-up time when the
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signal occurs.
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Dependencies:
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- ``CONFIG_TIMER`` – The timer driver must be selected.
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- ``CONFIG_DEV_GPIO`` – The GPIO driver must be selected.
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Note: You should also select one timer instance and have the gpio driver
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properly configured in your board logic.
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Example configuration:
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- ``EXAMPLES_TIMER_GPIO_TIM_DEVNAME`` – This is the name of the timer device
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that will be used. Default: ``/dev/timer0``.
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- ``EXAMPLES_TIMER_GPIO_GPIO_DEVNAME`` – This is the name of the gpio device
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that will be used. Default: ``/dev/gpio0``.
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- ``EXAMPLES_TIMER_GPIO_INTERVAL`` – This is the timer interval in
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microseconds. Default: ``1000000``.
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- ``EXAMPLES_TIMER_GPIO_SIGNO`` – This is the signal number that is used to
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notify that a timer interrupt occurred. Default: ``32``.
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- ``EXAMPLES_TIMER_GPIO_STACKSIZE`` – This is the stack size allocated when the
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timer task runs. Default: ``2048``.
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- ``EXAMPLES_TIMER_GPIO_PRIORITY`` – This is the priority of the timer task.
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Default: ``255``.
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- ``EXAMPLES_TIMER_GPIO_PROGNAME`` – This is the name of the program that will
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be used from the nsh. Default: ``timer_gpio``.
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