Modbus Rtu Master / Slave Communication - Panasonic FP-XH Series User Manual

numbers and memory addresses and executing F145 (SEND) / F146 (RECV) instructions in
a user program, because PLC automatically creates messages according to the protocol.
● A computer or display connected to PLC has the transmission right in slave communication.
Slave communication is performed when the device sends a command, and PLC returns a
response. In slave communication, no communication program is required on the PLC side,
because PLC automatically returns a response.
● The data size that can be sent or received at a time is a maximum of 507 words for register
transmission, 509 words for register reception, and 1 bit for bit transmission or reception.
Master function
Master
PLC
Slave function
Master
Devices that
support
MEWTOCOL
master function
■
Purpose of MEWTOCOL master communication (example)
This is used for connection with devices that support MEWTOCOL (Panasonic PLC protocol).
● Programmable controller FP series
● Displacement sensor HL series
● Eco-power meter KW series
■
Purpose of MEWTOCOL slave communication (example)
This is used for connection with devices that support MEWTOCOL-COM master communication
(Panasonic PLC protocol).
● Programmable displays from other manufacturers

1.2.3 MODBUS RTU Master / Slave Communication

■
Overview of function
● Used for communication with other devices that support the MODBUS RTU protocol.
WUME-FPXHCOMG-02
Slave
RS-485
Devices that
support
MEWTOCOL
slave function
Slave
RS-485
PLC
1.2 Overview of Communication Functions
Slave
Devices that
support
MEWTOCOL
slave function
Slave
PLC
Slave
Devices that
support
MEWTOCOL
slave function
Slave
PLC
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