FCI ST100A Series, Installation, Operation And Maintenance Manual

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ST100A Series Flow Meter OPERATION
Fluid Components International LLC 59
HART Command List Reference
The HART commands are divided into three classes.
● Universal Commands
● Common Practice Commands
● Device Specific Commands
Barring no communication error, a field or slave device returns a response code as part of the 2-byte status response to a command. Refer
to Command Status Bytes on page 73 . The ST100A Series response codes listed in the following command summaries are a subset of the
response codes listed in the HART specification.
ST100A Series HART Universal Commands
The ST100A Series HART supports Universal Commands 0 through 22 and 38 and 48. Commands 4 and 5 are reserved under Universal
Command Specification Rev. 7.1 (HCF_SPEC-127, Revision 7.1) and not implemented in this specification. There is no HART command
10. Table 12 below summarizes the instrument’s HART Universal command set and the data associated with each command.
Table 12 – HART Universal Commands
Command 0: Read Unique Identifier
Byte Format Description
Request Data Bytes None
Response Data Bytes 0 Unsigned-8 254
1–2 Enum Expanded Device Type
3 Unsigned-8 Minimum number of preambles from master to slave
4 Unsigned-8 HART Protocol Revision Number: 7
5 Unsigned-8 Device Revision Number
6 Unsigned-8 Software Revision Number
7 Unsigned-5 (Most Significant 5 Bits) Hardware Revision Level
7 Enum Physical Signaling Code: 00 = Bell 202 Current (4-20 mA)
8 Bits Flags: (Unused)
9–11 Unsigned-24 Device ID
12 Unsigned-8 Minimum number of preambles from the slave to master
13 Unsigned-8 Maximum Number of Device Variables
14–15 Unsigned-16 Configuration Change Counter
16 Bits Extended Field Device Status
17–18 Enum Manufacturer ID Code: 166
DEC
/00A6
HEX
(FCI)
19–20 Enum Private Label Distributor Code
21 Enum Device Profile = 1 “HART Process Automation Device”
Response Codes See Table 17 , page 74 , for response code list.
Command 1: Read Primary Variable (Flow Units, & Flow Value)
Byte Format Description
Request Data Bytes None
Response Data Bytes 0 Enum Primary Variable Units Code
1–4 Float Primary Variable Value
Response Codes See Table 17 , page 74 , for response code list.