Rockwell Automation 1407-CGCM Combination Generator Control Module - Manual (Page 125)

Rockwell Automation Publication 1407-UM001G-EN-P - April 2013
125
Chapter
6
CGCM Unit Software Interface
Introduction This chapter provides information on communicating with the CGCM unit by
using the ControlNet network. It discusses scheduled and unscheduled
messaging between the ControlLogix controller and the CGCM unit and
touches briefly on the user program communication interface.
The Summary of Data Tables on page 126 provides an overview of the
module-defined Data Types that are created in the ControlLogix controller when
a CGCM unit is created.
Other tables display the content and format of the Data Types in greater detail.
CGCM Unit Firmware Revision Considerations
Controller tags are created when a CGCM unit is added to the ControlLogix
controller project. The module-defined data type depends on the major firmware
revision selected. If you need to change the major firmware revision in the
ControlLogix project you must delete the CGCM unit from the controller I/O
configuration and install it again with the correct firmware revision selected.
In revision 3. x and later the size of the Unscheduled Write data type was
increased from 64 bytes to 76 bytes.
Use the <CGCM>.C.UnschWrite controller tag as the source tag for the
unscheduled write with either firmware revision (where <CGCM> is the name
of the CGCM unit in the controller I/O configuration). The data in this tag is
accessed by using the Gain and Voltage tabs in the module properties dialog box.
Set the length of the unscheduled write message to 64 bytes for firmware revision
2.
x and 76 bytes for revision 3.x and later.
If an unscheduled write with length of 76 bytes is attempted to a CGCM unit
with firmware revision 2.
x, the message returns an error due to the data size
mismatch.