Specifications

Table Of Contents
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(2) Event task
The event task is used to execute the SFC program when an event occurs.
The event includes the following:
(a) Constant cycle
The SFC program is executed periodically at a cycle of 0.8ms, 1.7ms, 3.5ms,
7.1ms or 14.2ms.
(b) External interrupt (16 points of I0 to I15)
The SFC program is executed when the QI16 (16-point interrupt unit
mounted in motion slot) input set to the event task turns ON.
(c) PLC interrupt
The SFC program is executed when the GINT command is executed by the
sequence program for another units Q-PLC CPU.
POINT
(1) It is possible to set the multiple events in one SFC program. However, multiple
constant cycles cannot be set.
(2) The motion control step cannot be executed during an event task.
(3) NMI task
The SFC program is executed when the external interrupt (16 points of QI60)
input set for the NMI task turns ON.
POINT
(1) The NMI task has the highest priority in normal task/event task/NMI task.
(2) Even if the event task prohibit (DI) is executed by the normal task, the NMI
task interrupt is not masked, but is executed.
(4) Execution status example
The following shows an SFC program execution example when the SFC program
is executed by multiple tasks.
NMI task execution program
3.5ms event task execution program
Normal task execution program
3.5ms
NMI interrupt
NMI interrupt
When there is a program to be executed by the NMI task, a program to be
executed by the 3.5ms constant cycle event task and a program to be executed
by the normal task, each task is executed as shown below.
(a) 3.5ms constant cycle event task is executed every 3.5ms
(b) NMI task is executed at highest priority when the NMI interrupt is input
(c) Normal task is executed during dead time