Panasonic FP0R Series, Руководство пользователя

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7.4 Computer Link
7.4.1 Overview
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Computer link is used for communication with a computer connected to the PLC. Instructions
(command messages) are transmitted to the PLC, and the PLC responds (sends response messages)
based on the instructions received.
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A proprietary MEWNET protocol called MEWTOCOL-COM is used to exchange data between the
computer and the PLC.
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The PLC answers automatically to the commands received from the computer, so no program is
necessary on the PLC side in order to carry out communication.
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There are a MEWTOCOL master function and a MEWTOCOL slave function for the computer link.
The side that issues commands is called master, and the side that receives the commands, executes
the process and sends back responses is called slave.
MEWTOCOL master function
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This function is to carry out the communication on the master side (side that issues commands) of the
computer link. It is executed with the PLC's instruction F145(SEND) or F146(RECV). It is not necessary
to write the response process as a ladder, so the program is easier than the general-purpose
communication function.
The 1:1 or 1:N communication is available between our devices equipped with the computer link function
and the MEWTOCOL-COM. [Our devices (e.g.)] : PLC, temperature control unit, eco-power meter,
machine vision
MEWTOCOL slave function
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This function is to receive commands from the computer link, execute the process and send back the
results. Any special ladder program is not necessary to use this function. (Set the communication
conditions in the system registers.) It enables the 1:1 or 1:N communication with a master computer or
PLC.
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The program for the computer side must be written in BASIC or C language according to the
MEWTOCOL-COM. MEWTOCOL-COM contains the commands used to monitor and control PLC
operation.
Note:
It is necessary to set the system register of the communication port to the computer link for using this
function. Both the master and slave functions are available for the FP0R, however, only the slave
function is available for the tool and USB ports.