Mitsubishi MELSEC LJ71C24, User Manual

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9 DATA COMMUNICATION USING THE PREDEFINED PROTOCOL
9.5.2 Communication data
In the program example, the predefined protocol communication described below is
performed between LJ71C24 and the target device.
(1) Target device and protocols
Connect the LJ71C24 and the inverter and read out the operation mode values of
the inverter.
Set the inverter station number to CPU device (D300) and send it, and store the
operation mode value in CPU device (D201).
CPU
D300
D201
Set the inverter
station number
in the CPU device
(D300)
Operation
mode value
Inverter
station number
FREQROL-A700
CPU
Device
Check
code
D300
Inverter
station number
Header
Check
code
Operation
mode value
Store the operation
mode value
in the CPU device
(D201)
Terminator Header
Terminator
D201
Manufacturer Mitsubishi Electric
Device name FR-A700
Protocol name H7B:RD Operation Mode
(2) Storage devices for send/receive data, buffer memory assignment
Specify the device memory of a CPU module and buffer memory as the data
storage areas as shown in the table below, and send/receive data.
Packet name Element name Packet type
Data storage area
specification
H7B:RD Operation Mode Inverter Station Number Send packet D300
Inverter Station Number D200
NOR:RD Data(4 Digits Data)
Read Data
Receive packet
D201
Inverter Station Number D202
ERR:NAK Response
Error Code
Receive packet
D203