Mitsubishi Electric Melsec Q Series User Manual page 184

6 DEDICATED INSTRUCTIONS
Functions
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(1) This instruction designates the target network number and target station number
of a station connected to other networks or Ethernet in the control data and reads
the data of designated word devices of that station.
When reading the device data is completed, the completion device designated by
(D2) turns on.
[Local station]
Programmable
controller CPU
(D1)
READ
(2) Device data can be read from stations connected to other networks or Ethernet
having the specified network number, in addition to stations connected to the local
station's network.
(3) The data link instruction and instructions for the Ethernet network system cannot
be executed at two or more locations for the same channel.
If the execution conditions are met at two or more locations at the same time,
instructions to be executed later have to wait until the channel becomes available
because handshaking is automatically performed at the execution of the first
instruction.
(4) Whether the READ instruction is being executed or has been completed normally
or abnormally can be checked with the completion device (D2) or completion
status display flag ((D2) + 1) designated in the set data.
(a) Completion device (D2)
Turns on at the END processing of the scan where the READ instruction is
completed, and turns off at the next END processing.
(b) Status display device at completion ((D2) + 1)
Turns on and off depending on the completion status of the READ instruction.
Normal completion: Stays off and does not change.
Abnormal completion: Turns on at the END processing of the scan where
[Response station]
Ethernet module
Channel 1
(S2)
Channel n
Channel 8
the READ instruction is completed, and turns off at
the next END processing.
MELSEC-Q/L
Programmable
Ethernet module
controller CPU
Ethernet
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