Starting And Ending A Block - Mitsubishi Electric MELSEC iQ-R Series Programming Manual

Starting and ending a block

Starting a block
A block in the SFC program can be started by either of the following methods.
Item
CPU parameter
(auto start, only for block 0)
Block start step
SFC control instruction
SFC information device
Engineering tool
Ending a block
A block in the SFC program can be ended by either of the following methods.
Item
End step
SFC control instruction
SFC information device
Engineering tool
8 SFC PROGRAM
142
8.7 SFC Program Execution
Method
Set "Auto-start block 0" to "Start Conditions Setting" in the
CPU parameter. When the SFC program is executed,
block 0 starts automatically and processing is performed
sequentially from the initial step.
Start another block by using a block start step [BC or BS]
in a block.
Start the block specified by the SFC control instruction
used in the action of the SFC program or in another
sequence program.
• Use the SET [BL] (Starting a block) instruction to
execute the program from the initial step of the
specified block.
• Use the SET [S/BL\S] (Activating a step)
instruction to execute the program from the specified
step of the specified block.
Start the specified block by turning on the block START/
END bit set to each block.
Start the specified block by turning on the SFC block
device.
Method
Execute the end step in a block. Processing is stopped
and the block becomes inactive.
End and deactivate the block specified by the RST [BL]
(Ending a block) instruction used in the action of the SFC
program or in another sequence program.
(The block ends when all the active steps in the specified
block are deactivated by using the RST [BL\S]
(Ending a block) instruction.)
End the specified block by turning off the block START/
END bit set to each block.
End the specified block by turning off the SFC block
device.
Remarks
This method is used to use block 0
as a control block, preprocessing
block, or continuous monitoring
block.
This method is effective when the
control sequence is clear.
This method is effective to restart
the error processing block or
execute interrupt processing.
This method is effective for
debugging (in units of blocks) and
test operation because blocks can
be restarted even from external
devices.
This method is effective for
debugging and test operation.
Remarks
This method is effective to stop
operation by stopping a cycle in
automatic operation.
This method is effective to end
processing regardless of the
operation status, such as an
emergency stop.
This method is effective for
debugging (in units of blocks) and
test operation because blocks can
be ended even from external
devices.
This method is effective for
debugging and test operation.
Reference
Page 132 Start
condition setting
Page 99 Block
start step (with END
check) [BC]
Page 100 Block
start step (without END
check) [BS]
Page 119 SFC
Control Instructions
Page 122 Block
START/END bit
 GX Works3
Operating Manual
Reference
Page 101 End
step
Page 119 SFC
Control Instructions
Page 122 Block
START/END bit
 GX Works3
Operating Manual