Rockwell Automation 1756-OF8H ControlLogix HART Analog I/O Modules - Manual (Page 125)

Rockwell Automation Publication 1756-UM533C-EN-P - February 2011 125
Getting HART Data By Using CIP MSG Chapter 8
Read Additional Status (Service Code = 16#4C)
These tables show the request and reply packet structures for the Read Additional
Status service. Reply Size = 2…224 bytes.
Table 34 - Request Packet
Offset Field Data Type Definition
No request data
Request size = 0 bytes
Table 35 - Reply Packet - Request Failed
Offset Field Data Type Definition
0 Status USINT Command status
1 Pad Pad byte
Reply size = 2 bytes
Request Failed
Table 36 - Reply Packet - Request Succeeded
Offset Offset Data Type Definition
0 Status USINT Command status
1 Count Number of Ext Status bytes available
2
…
26 Ext Status Bytes Extended Status bytes returned by CMD48
7 Pad Pad type
Reply Size = Instance 1…8: 2…28 bytes; Instance 0: 224 bytes. If sent to Instance 0, all channels of the module will be included in the response, resulting
in 28 bytes per channel (27 bytes of response to the HART Read Additional Status plus 1 byte of pad to align the data to a 32 bit boundary.)