Omron E3X-CIF11, Operation Manual

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Explicit Message Communications Section 2-6
2-6 Explicit Message Communications
Sending DeviceNet explicit messages from the master to the Communication
Unit enables reading or writing any parameters of Fiber Amplifier Units. The
Communication Unit processes the command sent from the master and
returns a response.
2-6-1 Basic Format of Explicit Messages
The basic formats of command and response blocks are shown here.
Command Block
Destination Node Address
Specifies the node address of the Unit to which the explicit message (com-
mand) is to be sent as a 1-byte hexadecimal value.
Service Code, Class ID, Instance ID, Attribute ID
Specify the command type, the Unit to receive the command, and other pro-
cessing details. The Fiber Amplifier Sensor Communication Unit uses the
instance ID to specify to Sensors for which the command is intended (Sensor
unit number). Some commands do not require an attribute ID.
Note The number of bytes specified for the class ID, instance ID, and at-
tribute ID depend on the master used. When the command is sent
from an OMRON DeviceNet Unit (master), the class ID and instance
ID are specified as 2 bytes (4 digits) each, and the attribute ID as 1
byte (2 digits).
Data
Data is not required for the READ command.
Response Block Normal Block
Error Block
Number of Received Bytes
The number of data bytes received starting from the source node is returned
as a hexadecimal value. When an error response is returned to an explicit
message, this value will be 0004 Hex.
Source Node Address
Returns the node address of the node from which the command was sent as
a hexadecimal value.
Destination
node
address Service
Code Class ID Instance ID Attribute ID Data
Number of
received
bytes Source node
address Service
Code Data
Number of
received
bytes fixed
at 0004 Hex Source node
address Service
Code Error Code