User Manual

Rockwell Automation Publication 1752-UM001E-EN-P - June 2014 265
Explicit Messages Appendix E
Restrictions on Sending Explicit Messages
Explicit messages are subject to the following restrictions.
• One address can be set in the user program for the trigger address.
• The SmartGuard controller’s internal I/O memory is sent as a response to
an explicit message. Explicit messages can be sent from a user program in
the controller, but internal information in the controller cannot be used as
send message data.
• Response data to explicit messages cannot be used in a SmartGuard
controller’s use program.
Accessing Controller
Parameters By Using
DeviceNet Explicit Messages
You can read and write to controller parameters by sending DeviceNet explicit
messages to the SmartGuard controller. The controller processes the received
messages and returns a response. The messages described in these tables are
supported by the SmartGuard controller.
ATTENTION: The data attributes handled by standard I/O communication and
explicit message communication is non-safety data. The necessary measures for
safety data are not taken during generation of standard or explicit message
data. Do not use this data to operate a safety control system.
Table 40 - Reading General Status
Explicit Message Service Function
Command
Response
Service
Code
Class ID
Hex
Instance ID
Hex
Attribute ID Data
Size
Read Unit General Status Read Reads the controller’s general
status
0E hex 39 hex 01 hex 6E hex -- 1 byte
Table 41 - Reading Safety Signature
Explicit Message Service Function
Command
Response
Service
Code
Class ID
Hex
Instance ID
Hex
Attribute ID Data
Size
Read Unit Safety Status Read Reads the SmartGuard’s Safety
Signature and Time Stamp
0E hex 39 hex 01 hex 1A hex -- 10 bytes