Cyclic Transmission Function (Periodical Communication) - Mitsubishi Electric Melsec QJ71LP21 Reference Manual

3 SPECIFICATIONS

3.2.1 Cyclic transmission function (periodical communication)

B0
B100
B200
The LB/LW information of
other stations on the network is
transmitted to each station.
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The cyclic transmission function periodically allows data communication between
stations on the same network using the link devices (LB/LW/LX/LY).
In this manual, the devices on the network module side are prefixed by "L" so that
devices on the CPU module side (B/W/X/Y) and the link devices on the network
module side can be distinguished.
(1) Communication using LB/LW
By using this function, it is possible to write data to the link relay (LB) and link
register (LW) of the network module and to send the data to all the stations
connected within the same network.
(a) Available device range
Assign the link devices (LB/LW) in the network within the valid range for
writing data of each station on the common parameter LB/LW setting
screen of the control station. In addition, the actual device range may be set
with the refresh parameters or the station inherent parameters for each
station.
(b) Data communication
The link relay (LB) can send and receive the on/off information and the link
register (LW) can send and receive 16-bit data.
For example, in a network consisting of a control station and two normal
stations, when B0 of the control station turns on, the B0 contacts of the two
normal stations turn on. At this point, the station inherent parameters have
not been set.
Common parameter
LB/LW settings
Control station 1M 1
P
B(LB)
0
Data
to sending
area of
1M 1
FF
P
100
Data
receiving
to
area of
1FF
1N 2
S
200
Data
receiving
to
area of
1N 3
S
2FF
LB/LW data of 1M
LB/LW data of 1N
Normal station 1N
0
LB/LW data of 1M 1
P to
FF
100
to
1FF
200
to
LB/LW data of 1N 2
S
2FF
1 LB/LW data of 1N 2
P S
3 LB/LW data of 1N
S
B(LB)
0
Data
B0
to receiving
area of
1M 1
FF
P
B100
100
Data
receiving
to
area of
1FF 1N 2
S
200
Data
sending
to
area of
1N 3
P
2FF
Normal station 1N 3
S
MELSEC-Q
2
P
B(LB)
Data
B0
receiving
area of
1M 1
P
Data
sending
B100
area of
1N 2
B200
S
Data
receiving
area of
1N 3
S
3
S
B200
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