Mitsubishi Electric MELSEC-Q Series User Manual page 225

(b) Receivable data size and receive data size
Set a receivable data size ((S1)+3) so that it will satisfy the following conditional expression:
Receivable data size ((S1)+3)  Receive data size ((S1)+4)
CPU module
Device
memory
Size
specified
in (S1)+3
If the receivable data size ((S1)+3) is smaller than the receive data size ((S1)+4), data sent from a remote
device station cannot be received.
The G(P).RDMSG instruction will fail (error code: B418
• When the receivable data size ((s1)+3) is an odd byte
If the receive data size is the same, 0 is stored in the upper byte of the last data.
CPU module
In the high
byte of the
last data,
Device
0 is stored.
memory
0
Master station
Size
Received
stored
data
in (S1)+4
Data are
not stored.
).
H
Master station
Received
data
CHAPTER 9 DEDICATED INSTRUCTIONS
Remote device station
Response
Remote device station
Response
9
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