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MELSEC-Q
3 SPECIFICATIONS
(2) When the sequence program is used
The following explains the I/O communication function when the sequence
program is used.
PLC CPU
QJ71DN91
Master node
I/O communication
request
1)
Slave function
receive
data area
0B00
H
0B3F
H
FROM
4)
0C00
H
0C3F
H
SET Y11
TO
X01
I/O communicating
3)
Slave function
transmit
data area
Transmission
Reception
5)
2)
X01
I/O communicating
[I/O communication]
1) Communication with the master node starts when the I/O
communication request (Y11) is turned ON.
[Reception data]
2) Transmission data from the master node is automatically stored in the
"slave function receive data" area of the buffer memory in the
QJ71DN91.
3) The transmission data from the master node, which is stored in the
"slave function receive data" area of the buffer memory, is loaded onto
the PLC CPU by the FROM instruction of the sequence program.
[Transmission data]
4) The TO instruction of the sequence program writes the ON/OFF
information to be sent to the master node in the "slave function transmit
data" area of the buffer memory.
5) The ON/OFF information, which is stored in the "slave function transmit
data" area of the buffer memory, is automatically sent to the master
node.