Azbil AUR355 - Fixed Length Continuous Data Write Command (WD Command)

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Chapter 4. Communication

Fixed length continuous data write command (WD command)
This command writes continuous data in two-byte units. This command is suitable
for handling data in ladder programs sent by PLC communications because the
data has a fixed length.
The start data address is expressed as four hexadecimal digits for WD. Data is
expressed as four × n (n is a positive integer) hexadecimal digits.
z
Command message
The write start address (four hexadecimal digits) and the number of data words to
write (four hexadecimal digits) are sent. (The letter n stands for the write count.)
z
Response message
If the command is successful, the Normal end code (two decimal digits) is returned.
If only part of the data is written, the Warning end code (two decimal digits) is
returned. If none of the data is written, the Error end code (two decimal digits) is
returned.
W

Writing of single data record
D

Writing of multiple data records
(1) Command
(2) Data start address
(3) Data 1
(4) Data 2 to (n−1)
(5) Data n
(1) (2) (3)
(5)
W
(1)
D
(2) (3) (4)
0

Normal end
(1)
0

When there is an error/warning
X
(1)
X
The end code (error/warning) is entered in place of XX.
(1) End code