Allen-Bradley 1404-M4, User Manual

Page: 332 / 356

Publication 1404-UM001D-EN-E - October 2004
G-8 Powermonitor 3000 ControlNet Device Profile
Behavior
The purpose of the Assembly Object is to act as a network interface to
the PM 3000’s data. That data can be accessed by a variety of means.
Instances 1 and 2 of the Assembly Object support Class 1 connections
in order to provide network scanners with access to the PM 3000’s I/O
data. Such messaging is said to be
I/O Messaging . The remainder of
the Assembly Object instances may be accessed via Unscheduled
Messaging ; either UCMM messages or Class 3 connections.
For reasons dictated by existing PM 3000 firmware functionality, the
way in which the Assembly Object accesses PM 3000 data differs for
writes as opposed to reads. Both I/O and unscheduled writes of data
to the PM 3000 are handled via interaction with the DPRAM task,
while reads are resolved directly from mirrored data within the DC’s
RAM.
Assembly Instance Data Map
See Table A.1 on page A-2 for information on the Assembly Instance
Data Map.
PCCC Object
The PCCC Object is a Rockwell Automation vendor specific object
which provides a way to handle PCCC messages encapsulated inside
CIP messages.
Class Attributes
The PCCC Object does not support any class attributes.
Instance Attributes
The PCCC Object does not support any instance attributes.
Class Code: 0x67 hex