Mitsubishi MELSEC LJ71C24, User Manual

Page: 128 / 428

9 - 18 9 - 18
9 DATA COMMUNICATION USING THE PREDEFINED PROTOCOL
The following explains the configuration of the data storage area.
(a) When "Fixed Number of Data/Variable Number of Data" is "Fixed Number
of Data"
An area starting from the device number which is specified on the Element
setting screen is considered as the data storage area.
Specified device
Data storage area
(Word)
+0
+n
Send packet: Users store the send data
Receive packet: The C24 stores the receive data
(b) When "Fixed Number of Data/Variable Number of Data" is "Variable
Number of Data"
An area starting from the device number which is specified on the Element
setting 1 is considered as the data storage area.
+1
+n
Data quantity storage area
Send packet: Users store the number of the send data
Receive packet: The C24 stores the number of the receive data
Data storage area
Send packet: Users store the send data
Receive packet: The C24 stores the receive data
(Word)
+0
Specified device
(c) Occupied size in data storage area
The size occupied in the data storage area varies depending on the
settings of "Conversion Unit" and "Number of Digits of Data".
Setting item
Conversion
Unit
Number of
Decimals
Occupied size in
data storage area
per one data
Reference for data storage area
configuration
No Decimal point
(fixed point)
1 word (d) Data storage area configuration 1)
Word
Variable point 2 words (d) Data storage area configuration 2)
No Decimal point
(fixed point)
2 words (d) Data storage area configuration 3)
Double
Word
Variable point 4 words (d) Data storage area configuration 4)