ABB FDNA-01, Руководство пользователя

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About the manual 21
ODVA™ ODVA stands for Open DeviceNet Vendor
Association. ODVA is an independent
organization that promotes interoperativity
between different manufacturers’ DeviceNet
products. ABB is an Associate Member at
ODVA.
Output In the ODVA DeviceNet specification the word
‘output’ is used to describe data flow from the
network into a device (such as FDNA-01).
Poll Message Most DeviceNet Scanners as well as the FDNA-
01 module support two different data services.
These are Poll and Change of State/Cyclic
messages.
The Poll Command is an I/O Message that is
transmitted by the master. A Poll Command is
directed towards a single, specific slave (point-
to-point, FDNA-01 always acts as a slave). A
master must transmit a separate Poll Command
Message for each of its slaves that is to be
polled. The Poll Response is an I/O Message
that a slave transmits back to the master when
the Poll Command is received.
Scanlist DeviceNet Scanner communicates with the
DeviceNet slaves in a user-defined order. This
order of communication is the scanlist. The
scanlist contains a complete list of the slave
nodes and the order in which the slaves are
accessed.
Term Explanation