Omron NE1A Series - Explicit Message Communications; Receiving Explicit Messages

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Explicit Message Communications Section 4-7
4-7 Explicit Message Communications
4-7-1 Receiving Explicit Messages
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.
Command Format
Response Format
• Normal Response to Explicit Message
• Error Response to Explicit Message
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.
4B 03 06
Destination node address
Class ID Instance ID
Data
Service code
Offset
address
Data size
CB
Number of receive b
y
tes
Read data
Originating node address
Service code
04
94
00
Number of receive bytes
Error code
Originating node Address
Service code