Campbell CR800 Series - Alternate Comms Protocols - Overview; Modbus - Overview

Section 5. Overview
78
• Peer-to-peer communication — no PC required. Special CRBasic
instructions simplify transferring data between dataloggers for
distributed decision making or control.
• Data consolidation — other PakBus dataloggers can be used as sensors
to consolidate all data into one Campbell Scientific datalogger.
• Routing — the CR800 can act as a router, passing on messages intended
for another Campbell Scientific datalogger. PakBus supports automatic
route detection and selection.
• Short distance networks — with no extra hardware, a CR800 can talk to
another CR800 over distances up to 30 feet by connecting transmit,
receive and ground wires between the dataloggers.
In a PakBus network, each datalogger is set to a unique address. The default
PakBus address in most devices is 1. To communicate with the CR800, the
datalogger support software
must know the CR800 PakBus address. The PakBus
address is changed using the CR1000KD Keyboard/Display
(p. 443), DevConfig
utility
(p. 103), CR800 Status table (p. 527), or PakBus Graph (p. 508) software.
5.3.5 Alternate Comms Protocols — Overview
Related Topics:
• Alternate Comms Protocols — Overview (p. 78)
• Alternate Comms Protocols — Details (p. 428)
Other comms protocols are also included:
• Web API
(p. 435, p. 435)
• Modbus
(p. 78)
• DNP3 (p. 79)
Refer to Specifications (p. 91) for a complete list of supported protocols. See Data
Retrieval and Comms Peripherals — Lists
(p. 568) for devices available from
Campbell Scientific.
Keyboard displays also communicate with the CR800. See Keyboard/Display —
Overview
(p. 80) for more information.
5.3.5.1 Modbus — Overview
Related Topics:
• Modbus — Overview (p. 78)
• Modbus — Details
(p. 436)
The CR800 supports Modbus master and Modbus slave communications for
inclusion in Modbus SCADA networks. Modbus is a widely used SCADA
communication protocol that facilitates exchange of information and data between