ICC ETH-1000, Инструкция по эксплуатации

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the area below the project tree. Refer to Figure 66. Also confirm that the
gateway’s “Network Status” LED should be solid green, indicating an
“online/connected” state.
By double-clicking “Controller Tags” in the project tree, it is possible to view
the newly-added tags. Refer to Figure 67. The gateway:C configuration tag
is unused, the gateway:I tag allows viewing of the input data, and the
gateway:O tag allows modification of the output data. These tags will be
synchronized with the gateway at whatever rate was established for the
module’s RPI. If desired, we can directly interact with these tags in order to
read and write data on the gateway.
Figure 67: Controller Tags for I/O Access
11.7.3.3 Explicit Messaging Reference and Examples
Class 3 (explicit messaging) can serve both as a direct method of accessing the
database and as a bypass mechanism to access data on devices connected to
the gateway by reference to “tag names”. Tags are read via the EtherNet/IP
“data table read” service, and tags are written via the EtherNet/IP “data table
write” service. Note that an underscore (“_”) is used to separate fields in the tag
names.
To read data from the gateway, the application PLC program must reference a
“source element” from which to start reading and the “number of elements” to
read. The “source element” will be a tag name constructed according to the
naming conventions shown in the following sections.
In a similar manner, to write data to the gateway, the application PLC program
must reference a “destination element” to which to start writing and the “number
of elements” to write. Again, the “destination element” will be a tag name
constructed according to the naming convention shown in the following sections.
Whether reading or writing, the “number of elements” can be any quantity from 1
to the maximum allowable length.