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Appendix A.7. Node Status Operation
When binding network variables on the FieldServer, the node status will be
When using a network tool to commission the FieldServer (implicit addressing), the FieldServer LonWorks Node must be placed ONLINE on the LonWorks network before it will pass data with other bound network variables. The following messages may appear on the driver screen when using Ruinet which indicates that the FieldServer has not been put into the ONLINE state yet:
"Not sending NV msg for [variable name], Node OFFLINE!"
To set the FieldServer to ONLINE using LonMaker:
On the Devices Tab, click the ONLINE button.
The FieldServer LonWorks Node is always ONLINE when using explicit addressing.
Note: The FieldServer Node_Status function (refer to the Bridge Configuration Manual) looks at the Node_ID configured in order to monitor Node status. In implicit applications this may not be the real Node_ID since Node_ID is allocated by the network manager.
Appendix A.8. Working with Binary Data
When sending binary data on a LonWorks network, there are two SNVT’s that are most commonly used, namely SNVT_State and SNVT_Switch.
SNVT_State is a 16 bit integer that allows the user to send 16 data bits to the remote device. To do this, the 16 data bits need to be packed into an integer word. If this packing is already done when the value is transferred into the FieldServer, then the SNVT need only be linked to the relevant Data Array offset for transfer out of the FieldServer. However, if the FieldServer is picking up 16 separate bits from another network for this variable, then the FieldServer Packed_Bit function can be used to achieve the packing. See the FieldServer Configuration manual for more details on the Packed_Bit function.
SNVT_Switch is a two byte value consisting of an analog value in the left hand byte (VALUE portion), and a binary state in the right hand byte (STATE portion). LonMark guidelines for this SNVT stipulate that the VALUE portion has a range from
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