Installation guide

Glossary
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CiA CAN in Automation. CiA is a non-profit group of manufacturers and users dedicated
to developing and supporting CAN-based higher layer protocols.
COB communication object. A communication object is a unit of transportation (a
"message") in a CAN-based network. Communication objects indicate a particular
functionality in a device. They are specified in the CANopen communication profile.
COMS island bus scanner.
configuration The arrangement and interconnection of hardware components within a system and
the hardware and software selections that determine the operating characteristics of
the system.
CRC cyclic redundancy check. Messages that implement this error checking mechanism
have a CRC field that is calculated by the transmitter according to the message’s
content. Receiving nodes recalculate the field. Disagreement in the two codes
indicates a difference between the transmitted message and the one received.
DeviceNet
protocol
DeviceNet is a low-level, connection-based network that is based on CAN, a serial
bus system without a defined application layer. DeviceNet, therefore, defines a layer
for the industrial application of CAN.
DHCP dynamic host configuration protocol. A TCP/IP protocol that allows a server to
assign an IP address based on a role name (host name) to a network node.
differential input A type of input design where two wires (+ and -) are run from each signal source to
the data acquisition interface. The voltage between the input and the interface
ground are measured by two high-impedance amplifiers, and the outputs from the
two amplifiers are subtracted by a third amplifier to yield the difference between the
+ and - inputs. Voltage common to both wires is thereby removed. Differential design
solves the problem of ground differences found in single-ended connections, and it
also reduces the cross-channel noise problem.
digital I/O An input or output that has an individual circuit connection at the module
corresponding directly to a data table bit or word that stores the value of the signal
at that I/O circuit. It allows the control logic to have discrete access to the I/O values.
DIN Deutsche industrial norms. A German agency that sets engineering and
dimensional standards and now has worldwide recognition.
D