MITSUBISHI ELECTRIC QJ71C24N - Manual (Page 23)

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Definitions and Descriptions of Terminology
The following table lists the definitions and descriptions of terminology used in this manual and related
manuals for the Q series serial communication modules.
Terms Description
A compatible IC frame
(Formats 1 to 4)
One of the message formats for the serial communication module for performing communication
using the MC protocol and ASCII code data.
This is the same message format as when communicating using the protocol for the A series
computer link modules. Device memory read/write operations for the QCPU are allowed within
the device range of the AnACPU.
For details, see Chapter 5 of the Reference Manual.
Bidirectional protocol
A communication procedure for the serial communication modules and one of the data
communication functions for communicating any data between the PLC CPU and an opposite
device. Details are explained in Chapter 7.
Independent operation
A mode of interface operation to communicate data with external devices using a function
specified in each communication protocol setting. Two interfaces of serial communication
modules do not interact.
Linked operation
The operation mode of each of the two interfaces for a serial communication module that are
connected to external devices and linked to one another in order to send/receive data to/from the
external devices.
The two interfaces communicate data using the identical data-communication function (MC
protocol (identical format) or non procedure protocol) and the identical transmission
specifications. (Linked operation using the bidirectional protocol is not allowed.)
MELSEC communication protocol
(MC protocol)
A communication procedure for the Q series serial communication modules or the Ethernet
interface modules, and a name of communication method for accessing to the PLC CPU from an
opposite device. (This is called the MC protocol in this manual.)
There are two communication methods; one uses ASCII code data and the other uses binary
code data.
Details are explained in the Reference Manual.
Message send function
(Printer function)
This function registers character data (messages) to be sent to external devices (mainly printers)
in the serial communication module as an user frame in advance, and sends the registered data
for multiple user frames using the non procedure protocol (sent by an instruction from the PLC
CPU).
Multidrop connection
A name of the connection when multiple external devices or other serial communication modules are
connected in a 1:n or m:n mode using the serial communication module's RS-422/485 interface.
Non procedure protocol
An user's communication procedure and one of the data communication functions for
communicating any data between the PLC CPU and an opposite device. Details are explained in
Chapter 6.
QnA compatible 2C frame
(Formats 1 to 4)
One of the message formats for the serial communication module for performing communication
using the MC protocol and ASCII code data.
This is the same message format as the communication frame using the protocol for the QnA
series serial communication modules.
• QnA compatible 2C frame (Formats 1 to 4): QnA simplified frame (Formats 1 to 4)
Details are explained in Chapter 4 of the Reference Manual.
QnA compatible 3C frame
(Formats 1 to 4)
QnA compatible 4C frame
(Formats 1 to 4)
One of the message formats for the serial communication module for performing communication
using the MC protocol and ASCII code data.
This is the same message format as the communication frame using the protocol for the QnA
series serial communication modules.
• QnA compatible 3C frame (Formats 1 to 4): QnA frame (Formats 1 to 4)
• QnA compatible 4C frame (Formats 1 to 4): QnA extension frame (Formats 1 to 4)
Details are explained in Chapter 3 of the Reference Manual.