Buffer Memory; Used Instruction - Mitsubishi FX3UC SERIES User Manual

FX Series Programmable Controllers
3UC
User's Manual - Hardware Edition
9.17

Buffer Memory

Data transfer between the PLC main unit and built-in master is executed by a program in the PLC.

9.17.1 Used instruction

1. "Built-in master → CPU" (Data read)
Read (transfer) the contents saved in the buffer memory (BFM) in the built-in master to a data register (D),
extension register (R) or auxiliary relay (M) for digit specification, etc. using an application instruction such as
FROM, MOV or BMOV instruction.
Example) Program to read the contents of the BFM #4 (abnormal station information) in the built-in master
(whose unit No. is fixed to 0) to D0
1) FROM instruction
M8000
FROM
2) Direct Specification of Buffer Memory (U[ ]\G[ ])
In case of the MOV instruction
M8000
MOV
Example) Program to read the contents of the BFM #0 to #3 (remote station connection information) in the
built-in master (whose unit No. is fixed to 0) to D10 to D13
1) FROM instruction
M0
FROMP
2) Direct Specification of Buffer Memory (U[ ]\G[ ])
In case of the BMOV instruction
M0
BMOVP U0\G0
2. "CPU Built-in master" (Data write)
→
Write (transfer) the contents of a data register (D), extension register (R) or auxiliary relay (M) for digit
specification, constant (K or H), etc. to the buffer memory (BFM) in the built-in master using an application
instruction such as TO, MOV or BMOV instruction.
Example) Program to write "H0" to the BFM #27 (command) in the built-in master (whose unit No. is fixed to 0)
1) TO instruction
M1
TOP
2) Direct Specification of Buffer Memory (U[ ]\G[ ])
In case of the MOV instruction
M1
MOVP
K0 K4 D0
Unit
BFM
Storage
No. 0 destination
#4
U0\G4 D0
Unit No. 0
Storage
BFM #4
destination
K0 K0 D10
Unit
BFM
Storage
No. 0 destination
#0
D10 K4
Unit No. 0 Number of
Storage
BFM #0
destination
transfer points
K0 K27 H0
Unit BFM Number of
Transfer
transfer points
source
No. 0 #27
data
H0 U0\G27
Transfer Unit No. 0
source BFM #27
data
9 CC-Link/LT Built-in master ability (Only FX3UC-32MT-LT)
K1
Number of
transfer points
K4
Number of
transfer points
K1
9.17 Buffer Memory
1
2
3
4
5
6
7
8
9
10
307