4. FUNCTIONS
4
−
4
MELSEC-A
4.2.2 Set attribute
1)
Set "Set Attribute" in the buffer memory message communication command area using
the sequence program TO instruction.
2)
Set the data to be written in the buffer memory message communication data area using
the sequence program TO instruction.
3)
Turn ON message communication request (Y(n+1)2) to write the data stored in the buffer
memory message communication data area to the special area of the slave station set by
the message communication command area.
4)
When the write operation is complete, the message communication result is stored in the
message communication results area of buffer memory.
5)
When the process result is stored in the message communication results area of buffer
memory, message communication ends and the message communication complete (Xn2)
signal automatically turns ON.
Slave station (MAC ID)
Class
Iinstance
DN91
PC CPU
Message communi-
cation request
Attribute
Attribute
Xn2
Message communication
complete
Following
processes
SET
Y(n+1)2
TO
Message communi-
cation complete
Class
Instance
Instance
Attribute
Attribute
Attribute
TO
Class
Instance
Attribute
Attribute
Instance
Attribute
0110
H
011F
H
Message
communication
command area
Message
communication
result area
Message
communication
data area
0130
H
01A7
H
0120
H
012F
H
1)
2)
3)
4)
5)