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8 INSTRUCTIONS FOR DATA LINK
8.3 Refresh Device Write/Read Instructions
• The station type which can and cannot specify with the start I/O number is as follows.
• Because the available range of the station number is 1 to 120, the station number for the master station in n1 cannot be
specified to (S1)+0. If the station number is specified, the "OPERATION ERROR" (error code: 4102) occurs.
• SM739 (Refresh device write/read instruction in execution flag) turns on during the instruction execution. When SM739 is
on, the following instructions cannot be executed.
If these instructions are executed, no processing is performed. When an error is detected at the instruction execution (before
SM739 turns ON), the completion device ((D2)+0), the completion device ((D2)+1), and SM739 do not turn on.
• The instruction completion can be checked in the completion device ((D2)+0 and (D2)+1).
• A module set parameters by the dedicated instruction and a CC-Link module operating by the automatic CC-Link startup
cannot be specified with the instruction.
• The read source (points in n2 from a device specified in control data) and read destination (points in n2 from (D1)) are
overlapped, data can be read. Read data starting from a device specified in control data when data are read to the smaller
device number. Read data starting from a device specified in control data + ((n2)-1) when data are read to the larger device
number.
Specification
possibility
Station type
Enabled CC-Link master station, CC-Link master station (compatible with redundant function), CC-Link IE Field Network master station
Disabled CC-Link local station, CC-Link standby master station, CC-Link IE Field Network local station, CC-Link IE Field Network submaster station
• S(P).REFDVWRB
•S(P).REFDVWRW
• S(P).REFDVRDB
• S(P).REFDVRDW
• Completion device ((D2)+0)
The device turns on at the END processing in a scan where the instruction is completed and turns off at the next END processing.
• Completion device ((D2)+1)
The device turns on or off by the status when the instruction is completed.
Normal completion: No change from off
Error completion: The device turns on at the END processing in a scan where the instruction is completed and turns off at the next END processing.
Sequence program
Completion device
Completion device + 1
S(P).REFDVRDW instruction
Refresh device write/read
instruction in execution flag
(SM739)
Scan Scan Scan
END
processing
END
processing
END
processing
Reading
device data
Instruction execution
Error completion
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