Omron CJ2 CPU - REV 10-2010 User Manual page 391

Example Write Protection Patterns
Connection pattern
From a computer
through a direct
serial connection
From a computer through a direct net-
work connection
From another PLC in the network
CJ2 CPU Unit Software User's Manual
Direct connec-
tion to PLC
USB port: USB (Toolbus)
Serial port: Toolbus
Gateway connec-
tion (Serial-to-
network) to PLC
USB port: USB (Toolbus)
Serial port: Toolbus
Computer
PLC#1
Diagram (example)
Computer
Write-protection not effective
Peripheral USB port
PLC
RS-232C port
RS-232C port or 422A/485 port
on a Communications Board/Unit
Computer
The CPU Unit in PLC #2
can be write-protected.
PLC #1
Network
The CPU Unit in PLC #2
can be write-protected.
PLC #1
Network
If the CMND instruction is used to send
a FINS command (requesting a write
CMND
operation) to the CPU Unit of PLC #2,
the operation is not performed.
The CPU Unit in PLC #2
can be write-protected.
PLC#2
Network
10 CPU Unit Functions
Write protec-
tion
Cannot be
applied.
Can be
applied.
PLC #2
Can be
applied.
PLC #2
Can be
applied.
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