How to access TR200 parameters
User-defined Network Variables UNVT
UNVT Parameter Structure
Two special User-defined Network Variables (UNVT) have been defined to enable access to TR200 parameters
via LonWorks:
Variable name:
UNVT type:
nviParamRequest
UNVT_param_request
nvoParamResponse
UNVT_param_response
The parameter or attribute request has the following structure:
UNVT_param_request
Field
Range
Type
Size
Request
1 = Read value
2 = Write value
Enum
1 byte
Par_number
Parameter number
Unsigned long
2 bytes
Subindex
Subindex (0-255)
Unsigned
1 byte
Value
Parameter value
Unsigned quad
4 bytes
The parameter or attribute response has the following structure:
UNVT_param_response
Field
Range
Type
Size
Response
0 = Error response
1 = Read response
2 = Write response
Enum
1 byte
Par_number
Parameter number
Unsigned long
2 bytes
Length
Length of “value” field (0–27)
Unsigned
1 byte
Value
Parameter or parameter attribute value
Unsigned
0–27 bytes
If an incorrect read or write request is encountered, an error message will be returned in the [Value] field, byte
0 and byte 3.
Error description:
Error code in Value [0]:
Error code in Value [3]:
Invalid request type
0xFF
1
Invalid parameter number
0xFF
2
Invalid data type
0xFF
3
No write access
0xFF
4
Exceed limits
0xFF
5
Invalid subindex
0xFF
6
Not array
0xFF
7
Only reset
0xFF
8
Not changeable
0xFF
9
Not in this mode
0xFF
10
No bus access
0xFF
11
Other error
0xFF
0xFE
TR200 LonWorks
7-1
