Rockwell Automation 20-COMM-D DeviceNet Adapter Series B FRN 2.xxx User Manual
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G-6
Glossary
20-COMM-D DeviceNet Adapter User Manual
Publication 20COMM-UM002G-EN-P
The Logic Status is used to monitor the PowerFlex 7-Class drive (for
example, operating state and motor direction). It consists of one 16-bit word
of input from the adapter to the network. The definitions of the bits in this
word depend on the drive, and are shown in
M
Master-Slave Hierarchy
An adapter configured for a master-slave hierarchy exchanges data with the
master device. Usually, a network has one scanner which is the master
device, and all other devices (for example, drives connected to DeviceNet
adapters) are slave devices.
On a network with multiple scanners (called a multimaster hierarchy), each
slave device must have a scanner specified as a master.
N
Node Address
A DeviceNet network can have as many as 64 devices connected to it. Each
device on the network must have a unique node address between 0 and 63.
Node address 63 is the default used by uncommissioned devices. Node
addresses are sometimes called ‘MAC IDs’.
NVS (Nonvolatile Storage)
NVS is the permanent memory of a device. Devices such as the adapter and
drive store parameters and other information in NVS so that they are not lost
when the device loses power. NVS is sometimes called ‘EEPROM’.
O
Objects
The DeviceNet specification defines an object as ‘an abstract representation
of a particular component within a product’.
P
PCCC (Programmable Controller Communications Command)
PCCC is the protocol used by some controllers to communicate with
devices on a network. Some software products (for example, DriveExplorer
and DriveExecutive software) also use PCCC to communicate.
Peer-to-Peer Hierarchy
An adapter that is configured for a peer-to-peer hierarchy can exchange data
with a device on the network that is not a scanner. This type of hierarchy can
be set up so that a scanner configures or transmits data to one PowerFlex
7-Class drive which then sends the same configuration or data to other
PowerFlex 7-Class drives on the network. To use a peer-to-peer hierarchy,
you configure one adapter to transmit data (2 or 4 words) and one or more
adapters to receive the data.
Ping
A message that is sent by a DPI product to its peripheral devices. They use
the ping to gather data about the product, including whether it can receive
messages and whether they can log in for control.