Specifications

Glossary
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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.
CSMA/CS
carrier sense multiple access/collision detection. CSMA/CS is a MAC protocol that
networks use to manage transmissions. The absence of a carrier (transmission
signal) indicates that a network channel is idle. Multiple nodes may try to
simultaneously transmit on the channel, which creates a collision of signals. Each
node detects the collision and immediately terminates transmission. Messages from
each node are retransmitted at random intervals until the frames are successfully
transmitted.
D
DDXML
Device Description eXtensible Markup Language
device name
A customer-driven, unique logical personal identifier for an Ethernet NIM. A device
name (or role name) is created when you combine the numeric rotary switch setting
with the NIM (for example, STBNIP2212_010).
After the NIM is configured with a valid device name, the DHCP server uses it to
identify the island at power up.
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 device name (host name) to a network node.