Instruction Manual Supplement
D103783X012
DVC2000 Digital Valve Controller
September 2017
13
CommonPractice Commands
The DVC2000 field device supports the following common practice commands:
Supported Commands
Command 33: Read Device Variables
Command 35: Write Primary Variable Range Values
Command 38: Reset Configuration Change Flag
Command 42: Master Reset
Command 44: Change Primary Variable Units Code
Command 48: Read Additional Status
Command 50: Read Dynamic Variable Assignments
Command 54: Read Device Variable Information
Command 108: Write Burst Mode Command Number
Command 109: Burst Control Mode
Command 33: Read Device Variables
This command is used to read the value of up to four selected Device Variables.
The Device Variables and the Variable Units Code are listed on page 6.
Note: If any one of the requested variable IDs is invalid, the INVALID_SELECTION error will be returned along with no
data bytes.
Byte Format Description Allowable choices
Request
Data Bytes
0 Variable ID Variable assigned to slot #0 See Device Variables on page 6
1 Variable ID Variable assigned to slot #1 See Device Variables on page 6
2 Variable ID Variable assigned to slot #2 See Device Variables on page 6
3 Variable ID Variable assigned to slot #3 See Device Variables on page 6
Response
Data Bytes
0 Variable ID Variable assigned to slot #0
1 Byte, hex Slot #0 Variable units code
25 Float Slot #0 Variable value
6 Variable ID Variable assigned to slot #1
7 Byte, hex Slot #1 Variable units code
811 Float Slot #1 Variable value
12 Variable ID Variable assigned to slot #2
13 Byte, hex Slot #2 Variable units code
1417 Float Slot #2 Variable value
18 Variable ID Variable assigned to slot #3
19 Byte, hex Slot #3 Variable units code
2023 Float Slot #3 Variable value
Code Class Description
Command
Specific
Response
Codes
2 Invalid selection – Invalid Variable ID (see note above)