Eaton EASY222-DN, User Manual

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DeviceNet Communication
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09/10 MN05013007Z-EN
General method of operation
The following is a description of the general operation with
the EASY222-DN. The acyclic data transfer is implemented
with the aid of explicit messages. The function blocks of the
easy basic unit can be addressed via the service code =
32
hex
. The assigned attribute ID is used here to distinguish
between different parameters and functions.
Note:
DeviceNet is based on the standard CAN protocol and there-
fore uses an 11-bit message identifier. As a result 2
11
=
2048 messages (000
hex
- 7FF
hex
) can be defined. As the
maximum number of stations on a DeviceNet network is 64
stations, 6 bits are used for identifying a device. These are
referred to as the MAC-ID (device or node address).
h
The DeviceNet connection of the easy control relay to an
SLC 500 requires specific control and handshake routines
in the PLC program for the execution of the control
commands (Explicit Messages).
The application note AN2700K17G supports the control
commands of EASY222-DN. It provides subroutines in the
program for controlling the required “Explicit Messages”,
i.e. the programming is replaced by the call and the
parameter assignment of the subroutine. Parameters are
assigned by means of an integer file.
The self-unpacking application note AN2700K17G.exe
(for easy600) is available at
https://es-assets.eaton.com/AUTOMATION/
APPLICATION_Notes/an27k17g.ex
e for download.
Service
code Object address
Class ID Instance ID
32
hex
64
hex
01
hex