Modelling with UML Activity diagram a program that update a system timer

Question

I'm trying to model an application with UML, and need some help.

• The program starts every 60 seconds by a system timer.
• The program is started with an argument called Type
• The first time the program i started after a system reboot, the program is started with argument 1.
• The program do what i should do, and get a new Type
• The program update the system timer so that the next time the program is started, it get the new Type as argument.
• The program then ends.

I'm thinking of modeling this with an activity diagrams, but do not know how.

I made the following experiment. Is that correct, or is it something that needs to be changed or can be improved?

Answer 1

Instead of using a parallel region, you should have one activity that has internal activities to depict your program. Something like this:

What you depict in your diagram is that the region inside the dotted line receives multiple inputs and processes them in parallel. Not what you want.

The OS part seems OK to me.