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Counter Alarm


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.


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


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


Building and Running

west build -b disco_l475_iot1 samples/drivers/counter/alarm
west build -t run

Sample Output

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>