Master/Local Modules - Mitsubishi Electric MELSEC-Q Series User Manual

1.2

Master/Local Modules

By using master/local modules, MELSEC-Q series programmable controllers can be connected to a CC-Link system.
Remotely-located devices in a CC-Link system can be controlled as if they were on the same base unit as the
master/local module.
The module works as a master station or a local station in CC-Link.
(1) Data communications
(a) Periodic communications (cyclic transmission)
Master/local modules can periodically exchange data with other stations in a CC-Link system. (
Section 8.1.1)
For example, I/O signals of remotely-located stations in a CC-Link system can be used in the same way as
those of the master station.
Terminating
resistor
CPU module
(b) Non-periodic communications (transient transmission)
Data can be communicated when a request is issued unlike cyclic transmission.
Direct access to buffer memory areas and devices in other stations can be performed in transient transmission.
( Page 173, CHAPTER 9)
CPU module
Remote
Master station
I/O station
Master Remote
station I/O station
RX RX
X
Y RY RY
RWw
W
RWr
Master station
Command
Instruction
Device
1234
H
Terminating
resistor
Remote device
station, intelligent
device station
Remote
Local station
device station
Intelligent
device station
RX RY
RY RX
RWw RWr
RWr RWw
Local station
CPU module
Write
request
Terminating
resistor
CHAPTER 1 FEATURES
Page 125,
Terminating
resistor
Local station
CPU module
Y
X
W
Device
1234
H
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