7 - 9 7 - 9
MELSEC-Q
7 PROGRAMMING WHEN EXECUTING THE MASTER FUNCTION
7.5.2 Example of message communication write
The following shows an example of a sequence program that writes attributes to node
number 3.
In sections enclosed with a dashed line, the area that is actually read and written as
well as the class ID, instance ID and attribute ID are different depending on the slave
node. Therefore, refer to the applicable manual of the slave node.
Attribute write
command
Attribute write
command
Attribute write
command
Sets write data in D30.
Sets the attribute write command.
Slave station of station number 3,
class ID = 1
Instance ID = 1
Byte length of transmission data = 1,
attribute ID = 3
Writes request data into the buffer
memory.
Sets the message communication
request.
Resets the message communication
request.
Error handling program
Executes attribute write if the master
communication status is either C0
H
or 40
H
.
Reads the master communication status.
Writes transmission data into the
buffer memory.
