Timer

Timer provides the time at which the Timer callback timeout and related information.

A simplified sequence diagram focusing only on the relevant events is shown below.

to_dataframe API returns a table which has the following columns.

Column	Type	Description
timer_event_timestamp	System time	Timer timeout.
callback_start_timestamp	System time	Callback start time
callback_end_timestamp	System time	Callback end time

Here, the timer firing time is calculated by the following,

$$t_{timeout} = t_{init} + n \times t_{period}$$

See also

• Timer API
• Trace point | callback_start
• Trace point | callback_end
• Trace point | rcl_timer_init