Time Viewpoint
Purpose
The Time Viewpoint focuses on the specific requirements and constraints of real-time event-driven systems, ensuring that they meet timing and performance criteria.
Design Concerns
Time Event Life Cycle View
Model Kind
The time event life cycle is illustrated with a UML state diagram.
Figure SDS-TE-LIFE illustrates the time event life cycle:
[0] Time Event constructed but disarmed.
[1a] The armX() operation with the 'interval' argument of 0 arms a one-shot time event
[1b] The armX() operation with the 'interval' argument of non-zero arms, a periodic time event
[2] A one-shot Time Event is automatically disarmed after it expires
[3a] A one-shot Time Event can be disarmed while it is armed and still timing out (the disarm() operation returns 'true').
[3b] A periodic Time Event can be disarmed when it is armed (the disarm() operation returns 'true')
[3c] An already disarmed Time Event can be disarmed (the disarm() operation returns 'false')
[4a] A one-shot Time Event can be rearmed while it is armed and still timing out (the rearm() operation returns 'true').
[4b] A periodic Time Event can be rearmed while it is armed (the rearm() operation returns 'true').
[4c] A disarmed Time Event can be rearmed (the rearm() operation returns 'false').
[5a] Arming an already armed one-shot Time Event is NOT allowed (QP/C++ Framework asserts)
[5b] Arming an already armed periodic Time Event is NOT allowed (QP/C++ Framework asserts)
Backward Traceability
Forward Traceability (truncated to 2 level(s))
