Mitsubishi Electric Melsec Q Series User Manual page 216

6 DEDICATED INSTRUCTIONS
Functions
[Local station]
Programmable
controller CPU
(D1)
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(1) This instruction reads the designated word device data of the station designated
with the target station network number and target station number in the control
data. The station must be connected to other networks or Ethernet.
When reading the device data from other stations is completed, the completion
device designated in (D2) turns on.
Also, when sending the device data designated in (S2) is completed, the device
on other stations designated in (D3) turns on.
Ethernet module
Channel 1
SREAD
Channel n
Channel 8
(2) Device data can be read from stations connected to other networks or Ethernet
having the specified numbers, 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 SREAD instruction is being executed or has been completed
normally or abnormally can be checked with the send/receive instruction flag
corresponding to the channel used, 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 SREAD 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 SREAD
instruction.
Normal completion : Stays off and does not change.
Abnormal completion: Turns on at the END processing of the scan where
[Response station]
Programmable
controller CPU
(S2)
Ethernet
the SREAD instruction is completed, and turns off at
the next END processing.
MELSEC-Q/L
Ethernet module
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