Specifications

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4.3 Direct Access to Link Device of Network Module (Direct Access)
The link devices (LB, LW, LX, LY, SB, SW) of the network module can be directly read
or written by the sequence program regardless of the link refresh of the PLC CPU.
The link devices that are not set within the range of the link refresh (which reads/writes
the link devices between the CPU and the network modules) with the network refresh
parameters can also be read or written.
With the direct access to the link devices, the link refresh time and the transmission
delay time can be shortened.
4.3.1 Operation of direct access
(1) Processing method
(a) Normal (link refresh) processing
Communicate to the other station by link refresh and link scan.
CPU
Other
station
B100
Network module
B0
Device memory
storage area
(B, W, X, Y, etc.)
Link refresh
Refresh data
storage area
Link data
storage area
Link scan
(b) Direct processing
Communicate to the other station by link scan.
CPU
Other
station
J10\B100
Network module
Device memory
storage area
(B, W, X, Y, etc.)
Link refresh
Refresh data
storage area
Link data
storage area
Link scan
J10\B0