Mitsubishi Electric MELSEC-Q Structured Programming Manual page 102

FXCPU Structured Programming Manual
[Device & Common]
2. File register ↔ Data register <Same-number register update function of the BMOV
instruction>
When a same file register is specified in both input variables
same-number register update function of the BMOV instruction is activated as described below.
FX /FX /FX
0N 1S U
In FX /FX PLCs, the special device M8198 reverses the BMOV instruction execution direction.
U 2C
Built-in memory
or
memory cassette
Program
memory
Program/
comment
D1000
File register
500 points
14 blocks
[A]
(7000 points)
maximum
Built-in memory
or
memory cassette
Program
memory
Program/
comment
D1000
File register
500 points
14 blocks
[A]
(7000 points)
maximum
• When updating the contents of file registers using the same-number register update function, make sure
that the file register number is equivalent between the input variable
Make sure also that the number of transfer points specified by "n" does not exceed the file register area.
If the number of transfer points exceeds the file register area, an operation error occurs and the BMOV
instruction is not executed.
• When input variables
located within the file register area and if the number of transfer points does not exceed the file register
area.
100
/FX PLCs do not support the same-number register update function.
2C
System RAM
D 0
Data
memory
Data register
D1100 D1100
Data register
Read
[B]
D1499 D1499
Data register
D7999
System RAM
D 0
Data
memory
Data register
D1100 D1100
Data register
Write
[B]
D1499 D1499
Data register
D7999
and are indexed, the instruction is executed if the actual device number is
and
Read
OFF
X002
EN
s
D1100
n
K400
• When X002 is set to ON while the BMOV instruction
execution direction reverse flag M8024 is OFF, the
contents of file registers in the area [A] in the program
memory are transferred to the data register area [B] in
the data memory as shown in the left figure.
Write
X001
X003
D1100
K400
M8001
Always OFF
during operation
• When X003 is set to ON while the BMOV instruction
execution direction reverse flag M8024 is ON, the
contents of data registers in the area [B] in the data
memory are transferred to the file register area [A] in the
program memory as shown in the left figure.
2 Devices in Detail
2.8 Data Register and File Register [D]
in the BMOV instruction, the
BMOVP instruction
M8024 execution
direction reverse flag: OFF
BMOVP
ENO
d
D1100
A same file register number
is specified.
BMOVP instruction
execution direction
M8024
reverse flag: ON
BMOVP
EN ENO
s d
D1100
n
A same file register number is specified.
BMOVP instruction
M8024
execution direction
reverse flag: OFF
and the input variable .