Basic Characteristics RAPID

Multitasking Basic Characteristics RAPID
doing, for example.
Synchronising using polling
This is the easiest way to do it, but the performance will be the slowest.
Persistents are then used together with the instructions WaitUntil, IF, WHILE or
GOTO.
If the instruction WaitUntil is used, it will poll internally every 100 ms. Do not poll
more frequently in other implementations.
Example
TASK 0
MODULE module1
PERS BOOL startsync:=FALSE;
PROC main()
startsync:= TRUE;
.
ENDPROC
ENDMODULE
TASK 1
MODULE module2
PERS BOOL startsync:=FALSE;
PROC main()
WaitUntil startsync;
.
ENDPROC
ENDMODULE
Synchronising using an interrupt
To use this method, a cross connection must be prepared between two I/O-signals; one
output cross connected to one input. The instruction SetDO, ISignalDI or WaitDI is
then used.
Example
In this example do1 is connected to di1.
TASK 0
5-40 RAPID Reference Manual