Explicit Message Communications; Receiving Explicit Messages - Omron NE1A Series Manual

Explicit Message Communications

4-7 Explicit Message Communications
4-7-1

Receiving Explicit Messages

Command Format
Response Format
Sending explicit messages from the Standard Master to the NE1A-series
Controller enables reading or writing any specified data or parameters of the
Controller. The Controller operates according to the command sent from the
master and returns a response.
The following example describes the I/O area read service provided by the
Controller. Refer to Appendix 3 DeviceNet Explicit Messages for details on the
services that are available.
NE1A-series Controller I/O Area Read
Reads the NE1A-series Controller's local I/O or the Safety Slave I/O area allo-
cated to the Controller from the master.
4B 03 06
Class ID
Service code
Destination node address
• Normal Response to Explicit Message
CB
Service code
Originating node address
Number of receive bytes
• Error Response to Explicit Message
00 04 94
Service code
Originating node Address
Number of receive bytes
Destination Node Address (Command)
Specifies in 1-byte hexadecimal the NE1A-series Controller's address of
the data to be read.
Service Code (Command/Response)
For commands, 4B hex is specified. For responses, the upper bit is turned
ON, and CB hex is returned.
Offset
Instance ID
address
Data
Read data
Error code
Section 4-7
Data size
83