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4 Data Exchange with the CPU Unit
4-2
CJ-series PROFINET IO Controller Unit Operation Manual for NJ-series CPU Unit (W511)
4-1
Data Exchange with the CPU Unit
Data exchange between this Unit and the CPU Units uses the I/O port and memory for CJ-series Unit
allocated to the PROFINET IO Controller Unit.
The CPU Units and CJ-series PROFINET IO Controller Units exchange data as shown in the table and
chart below.
4-1-1
Data Flow
Access methods from the
user program
AT specification destina-
tion
Data exchange timing
Unit data type
Device Variable for CJ-series
Unit
I/O port
During I/O refresh
Software switch
IO Controller status
IO Device detailed status
data
User-defined variable
Memory used for CJ-series
Unit
During I/O refresh
IO Device data
At I/O refresh after instruction
execution
IO Device Message
send/receive data for com-
munications instructions
System-defined variable
None
During I/O refresh
Unit Restart Flag, Communi-
cations Port Enabled Flags,
etc.