I-7242D user manual
I-7242D DeviceNet/Modbus RTU Gateway User’s Manual, July 2006, Version 1.1 23/124
3 DeviceNet System
3.1
DeviceNet network Introduction
DeviceNet is one of the kinds of the network protocols based on the CAN
bus which are mainly used for machine control in embedded network, such as
in textile machinery, printing machines, injection molding machinery, or
packaging machines. DeviceNet is a low level network that provides
connections between simple industrial devices (sensors, actuators) and
higher-level devices (controllers). It allows direct peer to peer data exchange
between nodes in an organized and, if necessary, deterministic manner. The
network management functions specified in DeviceNet simplifies project
design, implementation and diagnosis by providing standard mechanisms for
network start-up and error management. DeviceNet defines a
connection-based scheme to facilitate all application communications. A
DeviceNet connection provides a communication path between multiple
endpoints. The endpoints of a connection are applications that need to share
data. The figure 3-11 shows the DeviceNet layer in the control and information
layers.
Figure 3-1 DeviceNet layer
The DeviceNet Communication Protocol is based on the concept of
connections. One must establish a connection with a device in order to
exclude information with that device. To establish a connection, each gateway
implements Predefined Master/Slave Connection Set through the DeviceNet
network. After establishing the explicit connections, the connection is then
used to move information from one node to the other. Once IO connections
