Mitsubishi Q Series Programming Guide

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4 SFC PROGRAM CONFIGURATION
MELSEC-Q
: First five digits of serial No. are 04122 or later.
High Performance
Basic
QCPU
PLC CPU
Process
CPU
Applicable
CPU
Redundant
CPU
Universal
4.4.6 Block START & END instructions (s, r)
Usable Devices Programs Using Instructions Execution Site
Internal Device
(System, User)
Link Direct
J
\
SFC Program
Bit Word
File
Register
R
Bit Word
Intelligent
Function
Module
U
\G
Index
Z
Constant
K, H
Expansion
SFC
BLm\Sn
BLm\TRn
Other
BLm
Data
Type
Sequence
Program
Step
Transition
Condition
Block Step
Transition
Condition
D
Device
name
m is a block No.
s (BLm)
D
m is a block No.
r (BLm)
D
[Function]
(1) Block START instruction (sBLm)
(a) A specified block is forcibly activated independently and is executed from its initial step.
When there are multiple initial steps, all initial steps become active.
When the bock START/END bit of the SFC information devices has been set, the
corresponding bit device changes from OFF to ON.
(b) If the specified block is already active when this instruction is executed, the instruction will
be ignored (equivalent to the NOP instruction), and processing will continue.
(2) Block END instruction (rBLm)
(a) A specified block is forcibly deactivated independently.
When there are active steps, all are deactivated and the coil outputs are turned OFF.
When the bock START/END bit of the SFC information devices has been set, the
corresponding bit device changes from ON to OFF.
(b) If the specified block is already inactive when this instruction is executed, the instruction will
be ignored (equivalent to the NOP instruction) and processing will continue.
[Operation Error]
• Error No. 4621 occurs when the specified block does not exist or when the SFC program is in
the stand-by status.
[Program Examples]
(1) When X1 switches ON, the following program forcibly activates block1. When X2 switches ON,
it ends and forcibly deactivates block1.
aX1
sBL1
aX2
rBL1
Related Instructions
a) SFC diagram symbols
• Block START step (Bm
, Bm ) .................................See Sections 4.2.8 and 4.2.9.
b) SFC information device
• Block START/END bit....................................................See Section 4.5.1.

Mitsubishi Q Series Specifications

General

Brand	Mitsubishi
Model	Q Series
Category	Control Unit
Language	English