Sfc Program For Program Execution Management - Mitsubishi MELSEC-Q Series Programming Manual

5 SFC PROGRAM PROCESSING SEQUENCE

5.2.3 SFC program for program execution management

This SFC program can be used to manage the program execution sequence when multiple
program file switching is required.
In addition to a normal SFC program, only one block can be created and executed for a single file
of an SFC program for program execution management.
(1) How to create SFC program for program execution management
(a) Number of files and blocks
In addition to a normal SFC program, only one file of an SFC program for program
execution management can be created as a scan execution type program.
Only one block of the SFC program for program execution management can be created.
(b) Usable instructions
The SFC diagram symbols (except the block START steps ( m,
be used in an SFC program and the sequence instructions that can be used in transition
conditions can all be used.
POINT
If block start steps ( m ,
will occur during SFC program execution and the CPU module will stop the execution.
(2) Execution procedure
The program is started automatically when registered as a scan execution type program.
At end step processing, the initial step is reactivated and processing is repeated.
REMARKS
(1) Use the peripheral device to select between the SFC program for program execution
management and the normal SFC program.
For details regarding the setting procedure, refer to the GX Developer Operating Manual
(SFC).
(2) Periodic execution block settings (see Section 4.7.4) cannot be defined the SFC programs
for program execution control.
If a SFC program for program execution control is set in a periodic execution block, the
execution of the SFC program will not be performed.
(3) The Basic model QCPU, Universal model QCPU, and LCPU do not support SFC programs
for program execution management.
(4) The SFC program for program execution management cannot be set as a stand-by type
program. In addition, execution designation by POFF or PSCAN instruction cannot be
applied to the program.
(5) The SFC control instructions cannot be executed for the SFC program for program
execution management. (Refer to Section 4.4.)
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m ) are described, a "BLOCK EXE. ERROR" error (error No. 4621)
m)) and steps that can
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