Basic Characteristics RAPID

Multitasking Basic Characteristics RAPID
stringtosend:=”this is a test”;
startsync:= TRUE
ENDPROC
ENDMODULE
TASK 1
MODULE module2
PERS BOOL startsync:=FALSE;
PERS STRING stringtosend:=””;
PROC main()
WaitUntil startsync;
!read string
IF stringtosend = “this is a test” THEN
ENDPROC
ENDMODULE
11.3 Type of task
11.4 Priorities
Each extra task (not 0) is started in the system start sequence. If the task is of type
STATIC, it will be restarted at the current position (where PP was when the system was
powered off), but if the type is set to SEMISTATIC, it will be restarted from the beginning
each time the power is turned on.
It is also possible to set the task to type NORMAL, then it will behave in the same was
as task 0 (the main task, controlling the robot movement). The teach pendent can only
be used to start task 0, so the only way to start other NORMAL tasks is to use CommunicationWare.
The way to run the tasks as default is to run all tasks at the same level in a round robbin
way (one basic step on each instance). But it is possible to change the priority of
one task by putting the task in the background of another. Then the background will
only execute when the foreground is waiting for some events, or has stopped the execution
(idle). A robot program with move instructions will be in an idle state most of
the time.
The example below describes some situations where the system has 10 tasks (see Figure
5)
Round robbin chain 1: tasks 0, 1, and 8 are busy
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