Rockwell Automation 1794-OF8IH FLEX Isolated Input/Output HART Analog Modules - Manual (Page 91)

Publication 1794-UM065B-EN-E - September 2010
Configure Module Messaging 79
Enable Publishing HART Command 3 Variables
In the module configuration tag "ChXHARTCmd3Disable", make sure the
value is "0" for each channel that is connected to a HART device.
Accessing HART Data Using CIP Message Instruction (MSG)
The 1794-IF8IH and 1794-OF8IH modules support these broad categories of
MSG based HART access:
• CIP formatted messages to retrieve common HART data cached in the
module.
• CIP messages containing HART formatted commands that are passed
directly to the HART Field Device for processing. These are called Pass
through messages.
Fill in The Information Needed for a MSG Instruction
The "MSG" instruction is formatted as shown below.
IMPORTANT
If you previously selected "Input Data" for the Comm Format because
you are not using the HART Variables in your control system then set
all channels of the "ChXHARTCmd3Disable" configuration tag to "1"
for the best pass through messaging and Asset Management
Software performance.
CIP Message Format – Unconnected Message Header
Field Value Definition
Message Type "CIP Generic"
Service Code 0x0E Get Attribute Single-READ DATA
0x10 Set Attribute Single-WRITE DATA
Class Name 0x007D FLEX module object
Instance Name 1…8 Module location
1 = module adjacent to
adapter
Object Attribute 0x7E…0xA7 Selects Data Assembly or
function
(see Module Data Access
Assemblies)
Source Length
(applies to Set
Attribute
Single) Depends on data assembly selected Specifies size in bytes of
data to write to module