Mitsubishi MELSEC LJ71C24, User Manual

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9 DATA COMMUNICATION USING THE PREDEFINED PROTOCOL
The following explains the configuration of the data storage area.
(a) When "Fixed Length/Variable Length" is "Fixed Length"
An area starting from the device number which is specified on the Element
setting screen is considered as the data storage area.
The data storage area to be occupied varies depending on the setting of
"Unit of Stored Data".
y When "Lower Byte + Upper Byte" is selected, the same size as the
data length is occupied.
(However, when the data length of a send packet is an odd number,
the upper byte (lower byte for "Byte Swap") of the last device is not
sent. When the data length of a receive packet is an odd number, the
last data is stored with one byte of 00
H
.)
y When "Lower Bytes Only" is selected, twice the size of the data length
is occupied.
Specified device
Data storage area
(Word)
+0
+n
Send packet: Users store the send data
Receive packet: The C24 stores the receive data