National Instruments BridgeVIEW 用户手册

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© National Instruments Corporation
8-1
8
Servers
This chapter explains how to use servers with BridgeVIEW. BridgeVIEW 
supports several types of servers including OPC Servers, DDE Servers, 
and National Instruments Standard IA Device Servers.
OPC Servers are written to the OPC Foundation OPC Data Access 
specification and are provided by many companies. A DDE Server is 
any server that supports the DDE Server interface. IA Device Servers 
are a type of server developed by National Instruments. There are two 
implementations of IA Device Servers: VI-based and DLL-based. 
The DLL-based servers are also known as IAK Device Servers.
This chapter also describes how to install and configure the IA Device 
Servers available from National Instruments and how to view the server 
configuration within BridgeVIEW.
BridgeVIEW includes the NI-DAQ Server, an IA Device Server that 
supports National Instruments data acquisition boards and SCXI, on 
the BridgeVIEW Development System CD. Additional device servers 
for other devices such as PLCs also are available for BridgeVIEW 
on the BridgeVIEW Device Servers CD. For more information about 
BridgeVIEW device servers, inquire about the Device Servers CD, 
available from National Instruments.
What Are BridgeVIEW Device Servers?
BridgeVIEW device server is an application that communicates with 
and manages I/O devices such as PLCs, remote I/O (Input/Output) devices, 
remote BridgeVIEW Engines, and data acquisition plug-in cards. Device 
servers pass real-world tag values to the BridgeVIEW Engine in real time. 
Each server monitors the device items and encapsulates all device- and 
hardware-specific details, thereby establishing a device-independent I/O 
layer for BridgeVIEW.
An item in BridgeVIEW is a channel or variable in a real-world device. 
For more information about how to connect a tag to a server and item, 
see Chapter 3,