B&B Electronics GW-7472 - Manual - Manual (Page 39)

GW-7472 User Manual, Version 1.0, Dec 2010 --- 39
5.2 Explicit Message
Explicit Messages are applied for accessing all of the objects in the object model. The
specific instances and attributes for each Object C
lass are presented in “Appendix A:
EtherNet/IP Object Model ”. Before using Explicit Messages, you must use the Forward Open
service of the Connection Manager Object to build a connection between the EtherNet/IP
scanner and the GW-7472. Afterwards, the Explicit Message can be used.
5.4 Implicit Message
Implicit Messages are applied only for accessing the Input Instance 65
hex
and Output
Instance 66
hex
of the Assembly Object in the object model. Before using Implicit Messages, you
must use the Forward Open service of the Connection Manager Object to build a connection
between the EtherNet/IP scanner and the GW-7472. Afterwards, the Implicit Message can be
used.
5.5 UCMM
The UCMM are also applied for accessing all of the objects in the object model. The main
feature of the UCMM is that you can send the UCMM without building a connection. It is a
simple method for EtherNet/IP to get the information of all objects. However, because of using
UCMM without building a connection, the reliability of the message transmission is worse than
the Explicit Message.
5.6 Assembly Object
The GW-7472 supports one input instance, one output instance and one command
status instance in Assembly Object. Each of these instances is mapping to the register data of
the Modbus slaves. After you use the Utility to configure the GW-7472, the mapping information
between the registers of the Modbus slaves and the instances of the Assembly Object is
created by following the configuration order of the Modbus commands defined by the Utility. A