Campbell CR800 Series, Operator'S Manual

Page: 503 / 598

Section 11. Glossary
503
Term: IP trace
Function associated with IP data transmissions. IP trace information was
originally accessed through the CRBasic instruction IPTrace()
(p. 428)
and
stored in a string variable. Files Manager
setting
(p. 541)
is now modified to
allow for creation of a file on a CR800 memory drive, such as USR:, to store
information in ring memory.
Term: isolation
Hardwire comms devices and cables can serve as alternate paths to earth
ground and entry points into the CR800 for electromagnetic noise. Alternate
paths to ground and electromagnetic noise can cause measurement errors.
Using opto-couplers in a connecting device allows comms signals to pass, but
breaks alternate ground paths and may filter some electromagnetic noise.
Campbell Scientific offers optically isolated RS-232 to CS I/O interfaces as a
CR800 accessory for use on the CS I/O port. See the appendix
Serial I/O
Modules — List
(p. 563).
Term: JSON
J ava S cript O bject N otation. A data file format available through the CR800
or LoggerNet .
Term: keep memory
keep memory is non-volatile memory that preserves some settings
(p. 527)
during a power-up or program start up reset. Examples include PakBus
address, station name, beacon intervals, neighbor lists, routing table, and
communication timeouts.
Term: keyboard/display
The CR800 has an optional external keyboard/display. The CR850 has an
integrated keyboard/display. See appendix Keyboard/Display — List
(p. 569)
for other compatible keyboard/displays.
Term: leaf node
A PakBus node at the end of a branch. When in this mode, the CR800 is not
able to forward packets from one of its communication ports to another. It
will not maintain a list of neighbors, but it still communicates with other
PakBus dataloggers and wireless sensors. It cannot be used as a means of
reaching (routing to) other dataloggers.