zephyr

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Tomasz Bursztyka e18fcbba5a device: Const-ify all device driver instance pointers Now that device_api attribute is unmodified at runtime, as well as all the other attributes, it is possible to switch all device driver instance to be constant. A coccinelle rule is used for this: @r_const_dev_1 disable optional_qualifier @ @@ -struct device * +const struct device * @r_const_dev_2 disable optional_qualifier @ @@ -struct device * const +const struct device * Fixes #27399 Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>		2020-09-02 13:48:13 +02:00
..
src	device: Const-ify all device driver instance pointers	2020-09-02 13:48:13 +02:00
CMakeLists.txt	…
Kconfig	…
README.rst	…
prj.conf	…
sample.yaml	sanitycheck: inclusive language	2020-08-27 07:04:07 -04:00

README.rst

.. _alarm_sample:

Counter Alarm Sample
#####################

Overview
********
This sample provides an example of alarm application using counter API.
It sets an alarm with an initial delay of 2 seconds. At each alarm
expiry, a new alarm is configured with a delay multiplied by 2.

.. note::
   In case of 1Hz frequency (RTC for example), precision is 1 second.
   Therefore, the sample output may differ in 1 second

Requirements
************

This sample requires the support of a timer IP compatible with alarm setting.

References
**********

- :ref:`disco_l475_iot1_board`

Building and Running
********************

 .. zephyr-app-commands::
    :zephyr-app: samples/drivers/counter/alarm
    :host-os: unix
    :board: disco_l475_iot1
    :goals: run
    :compact:

Sample Output
=============

 .. code-block:: console

    Counter alarm sample

    Set alarm in 2 sec
    !!! Alarm !!!
    Now: 2
    Set alarm in 4 sec
    !!! Alarm !!!
    Now: 6
    Set alarm in 8 sec
    !!! Alarm !!!
    Now: 14
    Set alarm in 16 sec
    !!! Alarm !!!
    Now: 30

    <repeats endlessly>