Campbell Scientific CR200/CR200X-series Dataloggers - Manual (Page 145)

Section 14. PakBus Overview
Read More! This section is provided as a primer to PakBus ® communications.
Complete information is available in Campbell Scientific's "PakBus Networking
Guide", available at www.campbellsci.com .
The CR200(X) communicates with computers or other Campbell Scientific
dataloggers via PakBus ® . PakBus ® is a proprietary telecommunications protocol
similar in concept to IP (Internet protocol). PakBus ® allows compatible
Campbell Scientific dataloggers and telecommunications peripherals to
seamlessly link to a PakBus ® network.
14.1 PakBus Addresses
CR200(X)s are assigned PakBus ® address 1 as a factory default. Networks with
more than a few stations should be organized with an addressing scheme that
guarantees unique addresses for all nodes. One approach, demonstrated in
FIGURE. PakBus Network Addressing (p. 134), is to assign single-digit
addresses to the first tier of nodes, multiples of tens to the second tier, multiples
of 100s to the third, etc. Note that each node on a branch starts with the same
digit. Devices, such as PCs, with addresses greater than 4000 are given special
administrative access to the network
PakBus addresses are set using DevConfig, PakBusGraph, or the CR200(X)
status table. DevConfig (Device Configuration Utility) is the primary settings
editor for Campbell Scientific equipment. It requires a hardwire RS-232
connection to a PC and allows backup of settings on the PC hard drive.
PakBusGraph is used over a telecommunications link to change settings, but has
no provision for backup.
Caution Care should be taken when changing PakBus ® addresses with
PakBusGraph or in the status table. If an address is changed to an unknown
value, a field visit with a laptop and DevConfig may be required to discover the
unknown address.
14.2 Nodes: Leaf Nodes and Routers
• A PakBus® network consists of 2 to 4093 linked nodes.
• One or more leaf nodes and routers can exist in a network.
• Leaf nodes are measurement devices at the end of a branch of the PakBus®
web.
• Leaf nodes can be linked to any router.
• A leaf node cannot route packets but can originate or receive them.
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