mbed-os/features/nanostack/FEATURE_NANOSTACK/sal-stack-nanostack/docs/10_API_timer.md

Library Timer API

This chapter describes the timer functionality.

If an application requires a timer, it can allocate one with the eventOS_event_timer_request( ) function. Further to a successful allocation, the system timer event occurs.

Note: The library supports dynamic timer count at the application layer. The stack can multiplex a single timer for multiple purposes.

API Headers

To use Library Timer API, include the following header in your application:

#include eventOS_event_timer.h

Allocate timer

To allocate timer events:

int8_t eventOS_event_timer_request
(
	uint8_t		snmessage,
	uint8_t		event_type,
	int8_t		tasklet_id,
	uint32_t	time
)

Parameter	Description
snmessage	The timer ID defined by the application.
event_type	The event type to be sent to a tasklet when the timer expires. Usually ARM_LIB_SYSTEM_TIMER_EVENT.
tasklet_id	The tasklet ID of the event receiver.
time	The requested period in milliseconds. Resolution is 10ms.

Return value

0 If timer allocation was successful.

-1 If timer allocation failed.

Further to the allocated time period, the event OS library will transmit an event of which the sender, event type (event->event_type) and event->event_id, is indicating allocated timer identification.

Release timer

To cancel allocated timer events:

int8_t eventOS_event_timer_cancel
(
	uint8_t		snmessage,
	int8_t		tasklet_id
)

Parameter	Description
snmessage	The timer ID of the event to be cancelled.
tasklet_id	The tasklet ID of the event receiver.

Return value

0 If timer release was successful.

-1 If timer release failed, timer ID is invalid or the timer is already released.