Basic Functions; Communication With The Remote I/O Stations - Mitsubishi MELSEC Q Series User Manual

4 FUNCTIONS

4.2 Basic Functions

4.2.1 Communication with the remote I/O stations

PLC CPU
Network
parameters
Automatic
refresh
parameters
4 - 3
This section explains the basic functions of the QJ61BT11N.
Two types of communication modes are available for the CC-Link system: remote net
mode and remote I/O net mode.
(1) Remote net mode
In this mode, it is possible to communicate with all stations (remote I/O station,
remote device station, local station, intelligent device station, and standby master
station). Thus, various systems can be configured according to their applications.
(2) Remote I/O net mode
In this mode, a high-speed cyclic transmission is performed for a system
consisting only of the master station and remote I/O stations. Because of this, the
link scan time can be shortened when compared to the remote net mode.
The following provides an overview of the communication between the master
station and a remote I/O station using the remote I/O net mode. In the
communication with the remote I/O station, the on/off data of the switches and
indicator lamps are communicated through remote input RX and remote output
RY.
1)
3)
X Automatic refresh
4)
Y
Automatic refresh
[Data link startup]
1) When the PLC system is powered on, the network parameters in the
PLC CPU are transferred to the master station, and the CC-Link system
automatically starts up.
Master station
Network
parameters
Buffer memory
Remote input
Link scan
RX
Remote output
Link scan
RY
MELSEC-Q
Remote I/O station
2)
Input
5)
Output
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