Hart pass-through cip message layout details, Pass-through init (service code= 16#4e), Pass-through query (service code= 16#4f) – Rockwell Automation 1756-OF8H ControlLogix HART Analog I/O Modules User Manual
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Rockwell Automation Publication 1756-UM533C-EN-P - February 2011
Chapter 8
Getting HART Data By Using CIP MSG
HART Pass-through CIP
Message Layout Details
See the following tables for pass-through information.
Pass-through Init (Service Code= 16#4E)
These tables show the request and reply packet structures for the Pass-through
Init service.
Pass-through Query (Service Code= 16#4F)
These tables show the request and reply packet structures for the Pass-through
Query service.
Table 40 - Request Packet
Offset
Field
Data Type
Definition
0
HART Command
USINT
HART Command Number
(1)
(2)
1
HART Data Size
USINT
Number of Data Bytes for Selected HART Command
(1)(2)
2…256
HART Data bytes
As many bytes as in HART Data Size
HART Command Data
(1)
Request Size = 2…257 bytes
(1) See
for more information.
(2) If this field is displayed as SINT in RSLogix 5000 software, values > 127 appear negative.
Table 41 - Reply Packet
Offset
Field
Data Type
Definition
0
Status
USINT
Command Status
32 = Busy - try again later
33 = Initiated - command started - send Query to get the reply
35 = Dead - Device not online
1
HART Command
USINT
Echo of HART Command
(1)
2
Handle
USINT
Handle Used in Query Operation
3
Queue Space
Remaining
USINT
Number of Queues Still Available for This Channel
If status (bit 0) is 35, refer to
for the error code description.
Reply Size = 4 bytes
(1) If this field is displayed as SINT in RSLogix 5000 software, values > 127 appear negative.
Table 42 - Request Packet
Offset
Field
Data Type
Definition
0
Handle
USINT
Handle for Query (from Handle Field above)
(1)
Request Size = 1 byte
(1) If this field is displayed as SINT in RSLogix 5000 software, values > 127 appear negative.