Mitsubishi FX3U-232-BD User Manual page 271

FX Series PLC User's Manual - Data Communication Edition
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Important points
• The on-demand send processing signal (M8127 or M8427) turns ON when the PLC gives a request to
send data to the computer, and turns OFF when sending of the specified data is completed. Use this signal
for interlock to prevent giving two or more on-demand requests at the same time.
• While the on-demand send processing signal is ON, the PLC cannot receive commands sent from the
computer.
• Amount of on-demand data and number of data registers used for sending according to the unit
specification (word or byte)
When the specified unit is a word:
The amount of on-demand data is equivalent to the number of data registers to be sent.
When the specified unit is a byte:
Two on-demand data units use one data register for sending.
Example: When the amount of on-demand data is "5", the number of data registers for sending is "3".
7 Commands
7.13 On-demand Function
A
B
C
D
E
F
G
H
I
Apx.
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