NAiS FP2, Техническое руководство

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7-3
7.1.2
Unit Operation
Operation overview of computer link mode (1:1 communication)
The computer link mode is a function to read and write data and contact of the CPU unit by the host
computer.
When an command is sent from a host side, a response is returned from the PLC side. The formats of
commands and responses are determined by the MEWTOCOL-COM, which is the communication
protocol for the FP series of PLCs.
Programs for host side devices such as computers and display panels are created in accordance with
the protocol “MEWTOCOL-COM”. More than 20 types of commands are available, including commands
for reading and writing the data area and contacts, etc.
No program is necessary on the PLC side in order to carry out communication.
Example: When the contents of the data registers are read to a host computer
Operation Overview of computer link mode (C-NET 1:N communicaiton)
For a 1:N computer link, the computer is connected through a commercially available RS232C-RS485
conversion adapter, and the respective PLCs are wired using an RS485 cable.
The computer and the PLC communicate via commands and responses: The computer sends a
command specifying the unit number, and the PLC with that unit number sends a response back to the
computer.
Note) Lineeye SI-35 is recommended to be used as a conversion adapter.