Echelon LonPoint Application and Plug-In - Manual (Page 174)

13-8 Data Logger Functional Block
Network variable index (1 byte): Identifies which
of the input network variables to the data logger
received the update. Every logged point contains a
network variable index
Source address (2 bytes): Identifies the subnet/node
address of the device the logged data was received
from. This information is included with each record if
the Source Addr option is selected for the
corresponding Data network variable.
Time stamp (7 bytes): Identifies the time and date
when this record was logged. This is derived from the
DL-10 device’s Real Time Clock functional block (see
Setting the DL-10’s Real Time Clock, later in this
chapter). This information is included with each
record if the Timestamp option is selected for the
corresponding Data network variable.
Network variable value (The number of bytes
depends on the network variable type, may be from 1
to 31 bytes): The network variable length in bytes can
be acquired from the SNVT Master List (if the
network variable is a SNVT) or from the Attributes
tab of the Network Variable Properties dialog
accessed through the LonMaker Browser (see
Chapter 9 of the LonMaker for Windows User's
Guide). Every logged point contains a network
variable value.