User`s manual

25
TERMS
The following table lists the definitions and descriptions of terminology used in this manual.
Term Description
A compatible 1C frame
(Formats 1 to 4)
One of the message formats for the serial communication modules, which is used to perform ASCII data communication by
MC protocol.
This is the same message format as the one used 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.
Bidirectional protocol
A communication procedure for the serial communication modules, with which any data communication is available
between the programmable controller CPU and the other device.
Buffer memory
Memory of the intelligent function modules/special function modules, which is used for storing data sent to or received from
the programmable controller CPU (setting values, monitor values, etc.)
Device A memory of the programmable controller CPU used for storing data
GX Configurator-SC Setting and monitoring tool for the serial communication module (MELSOFT product)
GX Developer A programming tool for designing, debugging and maintenance (MELSOFT product)
Independent operation
Operation of each of the two interfaces on the serial communication module when data communication is performed with
other devices using the specified protocols respectively.
Intelligent function module MELSEC-Q/L series modules with functions other than I/O functions such as A/D and D/A conversion module
Linked operation
Operation of each of the two interfaces on the serial communication module that are connected to external devices and
linked one another in order to communicate 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 pre-defined protocol or
the bidirectional protocol is not allowed.)
MELSEC communication
protocol
(MC protocol)
A communication procedure for the Q series C24 or the Ethernet interface modules, and a communication method for
accessing a programmable controller CPU from an external device.
(This is called the MC protocol in this manual.)
There are two communication types; one uses ASCII code data and the other uses binary code data.
Message send function
(Printer function)
This function registers character data (messages) to be sent to external devices (mainly printers) to the serial
communication module as a user frame in advance, and sends the registered data for multiple user frames using the non
procedure protocol.
Multidrop connection
A name of the connection when multiple external devices or other C24s are connected on a 1:n or m:n basis using the
serial communication module's RS-422/485 interface.
MX Component
Active X

control library for serial communication (MELSOFT product)
Non procedure protocol
A communication procedure and one of the data communication functions for communicating any data between the
programmable controller CPU and the other device.
Packet Data string used for communication using pre-defined protocol with external devices
Pre-defined protocol
One of the data communication functions available for the QJ71C24N(-R2/R4) and LJ71C24(-R2). In data communication
between the QJ71C24N(-R2/R4) or LJ71C24(-R2) and an external device, data can be sent or received by using a protocol
for the external device.
This must be set in GX Configurator-SC (Pre-defined protocol support function).
Pre-defined protocol support
function
This function can be used in GX Configurator-SC (Pre-defined protocol support function).
The functional overview of the pre-defined protocol support function is indicated below.
• Protocol setting according to the opposite device
• The writing and reading of protocol setting data to QJ71C24N(-R2/R4) and LJ71C24(-R2) flash ROM
• Debugging support function
QnA compatible 2C frame
(Formats 1 to 4)
One of the message formats for the serial communication modules, which is used to perform ASCII data communication by
MC protocol.
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)
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 modules, which is used to perform ASCII data communication by
MC protocol.
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)