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Sending Explicit Messages Section 9-1
Class ID (command):
The class ID of the destination of the explicit message.
Instance ID (command):
The instance ID of the destination of the explicit message.
Service data (command, response):
The data defined for the services codes.
No. of bytes received (response):
The number of bytes received from the destination node address (remote
node).
Destination node address (remote node):
The node address of the OMRON Special I/O Slave Unit or Slave manufac-
tured by another company to which the explicit message was sent is returned.
Error code (response):
An error code defined in EtherNet/IP (1-byte general status and 2-byte addi-
tional status) is returned. The data format is DeviceNet-compatible (2 bytes
total), so the returned Error Code is converted to the 1-byte general status
and a 1-byte additional status (high byte only).
Description
• The EXPLICIT MESSAGE SEND command is used to send an EtherNet/
IP-defined explicit message to another company’s node and receive a
response.
• Unlike other FINS commands, the destination of a EXPLICIT MESSAGE
SEND command’s control data is the local node’s EtherNet/IP Unit or
built-in EtherNet/IP port, and the actual destination node is specified in
the command’s route path.
Always specify the local node’s EtherNet/IP Unit or built-in EtherNet/IP port
in the CMND(490) instruction’s control data. An error will occur if another
node’s Master Unit is specified as the destination.
• When an EtherNet/IP Unit or built-in EtherNet/IP port receives an explicit
message, it automatically returns a response to the message.
• A time of 2 s is used for request service processing timeouts.
Set the CMND(490) instruction’s timeout set value to 2 s or longer.
When there is a timeout, the error code will be 0102 hex.
When the CMND(490) instruction’s timeout set value is less than 2 s, a
FINS timeout error response of 0205 hex may occur.
Note 1. For details on the parameters of explicit messages, refer to the EtherNet/
IP specifications.
2. The Open DeviceNet Vendor Association, Inc. (ODVA) can be contacted at
the following address to obtain copies of the EtherNet/IP and CIP specifi-
cations.
ODVA Headquarters
4220 Varsity Drive, Suite A
Ann Arbor, Michigan 48108-5006
USA
TEL: 1 734-975-8840
FAX: 1 734-922-0027
Email odva@odva.org
WEB www.odva.org