Mitsubishi QD51, User Manual

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MELSEC-Q
3 SPECIFICATIONS
(3) Task Start Signal (Y19)
(a) This is a signal that starts the task designated by the start task No.
designation signal (Y11/Y12). The task start signal (Y19) cannot be used as
a general output even in cases where there is no task that is started by an
interrupt from the sequencer CPU. Also, if the task is compiled BASIC, it
cannot be started by an interrupt from the programmable controller CPU.
(b) The task start signal (Y19) is enabled only while the multitask execution
start signal (X0B) is ON.
(c) The designated task 1 is started when the task start signal (Y19) rises
(OFF ON). (Even if the start task No. designation signal (Y11/Y12) goes
ON while the task start signal (Y19) is ON, it is disregarded.)
Example
The example shows a program in the case where task 1 is started from the programmable controller
CPU.
[Conditions]
"IT (started by an interrupt from the programmable controller CPU)" is set with only task 1 set for
multitasking.
Task start signal Y19 OFF
Task 1 start signal Y11 OFF
2
ON
Task 1 executed
END
Task 1 setting designation
Y11
Task start command
Y19
1) 1 Since it is treated as a general output, starting of the task is not carried out.
2) 2 Since the task start signal is not changing from OFF ON, starting of task 1 is not carried out.
[Sequence Program]
ON
ON
Y12
ON
General output
treatment
Task 1 starts
1
OFF
(d) In the case of the task designated by the start task No. designation signal
(Y11/Y12) being in the process of starting, task start is disregarded.
(Operation of the currently executing task is continued.)
(e) If the exclusive command YCHECK is used, the task's starting time can be
shortened. Refer to Chapter 6 concerning the YCHECK command.