1 Overview
The COM interface incorporated in the server offers the client two object types: group
and item. A server object is automatically created after the client connects to the server.
Associated with each item is a time stamp, its quality and the value of the item as a
VARIANT type. The item tags--tag, node or property objects--have to be realized on the
server side.
The node objects can contain either other node objects or leaf objects. Node objects are
implemented as channel, device or tag group elements within the FP OPC Server. Tag
objects, which are implemented as tag elements, represent the leaf objects in the object tree.
The OPC client connected to the OPC server is responsible for the type of information
it retrieves. It has to define the group structure, the poll rate and the read type, i.e.
asynchronous or synchronous data retrieval. Using synchronous data retrieval, the client has
to wait until the read operation is finished; using asynchronous data retrieval, on the other
hand, allows the client to be informed immediately when data changes.
1.3
Features of the FP OPC Server
The Panasonic FP OPC Server is a
OutProc Server
, thus the server application is started
from an autarkic executable file. The server allows high-performance data transfer between
applications that support the OPC DA standard and Panasonic FP Series PLCs.
The following features are provided:
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Содержание FP OPC Server
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