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Lines 3-N: One or more lines per network variable mapping the variables to BACnet objects.
Each line represents one BACnet object whose type is shown in the first column.
Column 1 (NV index): This is the network variable index as defined by LonWorks protocol,
and will be found in the XIF file or manufacturer's documentation. You will have no need to
edit this column unless creating a device manually.
Column 2 (Direction): The direction here refers to direction as defined at the remote
LonWorks node. NVO is network variable output, meaning we can read this data. NVI is
network variable input, meaning we can write this data. Direction will be found in the XIF
file and MUST NOT be changed. Communication failure will result if direction is incorrect.
Column 3 (SNVT index): This is the Standard Network Variable Type as published in
LonWorks standards. Manufacturer defined network variables will translate to SNVT index
zero and must be interpreted as raw data. If a Manufacturer defined NV type is really a
renamed standard type, you can enter the standard type code here. (Note: You can
download a pdf file containing a complete definition of all network variable types at
www.lonmark.org. You WILL need this document to do anything more than the default
mapping created for you by xif2csvX2.exe. Due to copyright restrictions, we cannot provide
it for you.)
Column 4 (Raw type): When parsing a structured variable into multiple Modbus registers,
this field specifies the raw data type found in the respective field of the structure. These are
the enumerated NVT_CAT types (found in the enumeration section of the pdf document
mentioned above).
Column 5 (Offset): Structured variables are multiple bytes in length. This column provides
the byte offset from the first byte of the structure where this field or object is found.
Column 6 (Bit offset): Some structured variables treat individual bits as data elements, and
often there is a set of multiple bits in such a structure. The Offset column is used to access
the correct byte. The Bit offset is used to specify which bit this object refers to. Bit offsets
are 0..7 bit positions from the left (MSB of byte). To reiterate, a bit offset of 0 will result in
a byte mask of 0x80. Keep in mind that LonWorks SNVT bit structure definitions identify "bit
1" as the left most bit.
Columns 7, 8, 9 (Scale): These are the scale factors A, B, and C whose usage is as defined
for standard network variable types (see note about pdf file available above).
Column 10 (Group): This column flags the respective line as being a member of a "group"
or structured network variable. When the group flag is set, the gateway sees that it needs
to process multiple maps to arrive at a complete network variable for transmission on the
LonWorks network. This is especially important when writing a network variable to a
LonWorks device - all fields must be transmitted together.
Column 11 (Lock): This flag is only used in conjunction with the Group flag. When multiple
Modbus registers are mapped to a single network variable that will be written to the
LonWorks device, you have the option of that variable being updated when any member of
the structure is written from Modbus (default). You also have the option of causing the
entire structure to be updated ONLY when a certain member of the structure is updated. Set
the Lock field to 1 to indicate which member of a group is the Lock field. The structure will
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