Mitsubishi QJ71GP21-SX, Reference Manual

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DEFINITIONS OF TERMINOLOGY
Definitions of the terms used in this manual are explained below.
Term Description
Cyclic transmission
Using the link devices (LB/LW/LX/LY) of the CC-Link IE controller network module, data can be
transferred periodically between stations on the same network.
• LB/LW is used to send data of one station to all stations. (1:N communication)
• LX/LY is used to send data of one station to another station. (1:1 communication)
Transient transmission
This function allows communication with another station when a request is made with a
dedicated instruction or from GX Developer.
Link dedicated instruction
Dedicated instruction that is used for transient transmission with other programmable
controllers.
Communications can be made with programmable controllers on the same or other networks.
CC-Link dedicated
instruction Dedicated instruction that is used for transient transmission with CC-link IE controller network
compatible devices. This allows communication with a station on the same network.
RAS
Abbreviation for Reliability, Availability, and Serviceability.
This term is used to express the overall usability of automation systems.
Control station
Only one station that controls the network to which it is connected.
Each station's send range for cyclic transmission is assigned to the control station.
Normal station
Station that performs cyclic transmission according to the range assignment of the control
station.
Reserved station
Station that is not actually connected to the network.
It must be included in the total number of stations in the network, since it is to be connected in
the future.
Relay station
Station that relays transient transmission data to another network.
Link device data of a network module are transferred to another network module via this station.
Multiple network modules are connected to one programmable controller.
Undefined station
Station to which a station No. is to be set in the sequence program, however, that has presently
no station No. because the UINI instruction has not been executed yet.
Reconnection Processing of restarting data link when a faulty station becomes normal.
Disconnection Processing of stopping data link when a data link error occurs.
Device Devices (X, Y, M, D, etc.) that are contained in a CPU module.
Link device Devices (LB/LW/LX/LY) that are contained in a CC-Link IE controller network module.
Link scan time
Time required for data of each station to be sent in order and to make one rotation in the
network.
The link scan time changes depending on the data volume or transient transmission request.
Link scans are performed "asynchronously" with sequence scans of the CPU module.
Link refresh
Processing of data transfer between link devices of the CC-Link IE controller network module
and CPU module devices.
Link refresh is performed in "END processing" of the sequence scan of the CPU module.
Buffer memory Memory area in the CC-Link IE controller network module, in which data are temporarily stored.
Baton pass
A control mechanism in which transmission right (token) is passed around the network for data
transmission.
Control station switching
time Time taken from when the control station went down due to a reason such as power-off until
data link is started by the sub-control station.
Shared group No.
Number that is assigned to a station to allow it to share cyclic data with any given stations.
Cyclic data can be shared only with stations of the same group.
Group No.
Number that is assigned for transient transmission to any given stations.
By specifying a group of stations as transient transmission target, data can be sent to the
stations of the same group No.