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Application Note 184

National Instruments

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are trademarks of National Instruments Corporation. Product and company names mentioned herein are trademarks or trade

names of their respective companies. For patents covering National Instruments products, refer to the appropriate location: Help»Patents in your software, the

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Developing Wireless GPIB Test Systems

Using the GPIB-ENET/100

Introduction

The National Instruments GPIB-ENET/100 expands the options for size, distance, environmental conditions,

integration of test systems, and instrumentation location in your computer-controlled test applications. Adding

wireless connectivity and control in your test system further addresses concerns over environmental conditions,

distance, network cabling, and integration of test components throughout your company. Communication with your

instrumentation systems over a wireless connection gives you more versatility in the placement and the mobility of the

GPIB instrumentation system.

The NI GPIB-ENET/100 easily converts your existing instrumentation system into a wireless test system through the

use of off-the-shelf wireless routers and access points. This application note discusses background on wireless

networks, setting up a wireless GPIB test system, and configuring the wireless system.

Wireless Networks

Wireless local area networks (LANs) operating in a range of frequencies have been used since the early 1990s.

Previously, applications using custom wireless LAN technology were very limited in scope and typically required

extensive programming and testing. In 1998, the IEEE proposed a specification for wireless communication, setting

the foundation for IEEE Standard 802.11-2001.

Under IEEE 802.11, there are two types of network configurations – ad hoc and infrastructure. Under ad hoc networks,

there is no fixed access point – computers (or nodes) are able to communicate with any other computer. Although not

a very structured design, developers have created algorithms to ensure efficient communication in an ad-hoc network.

The infrastructure network architecture uses fixed access points to simplify communication between nodes. Oftentimes

these fixed access points are connected to landlines, such as existing Ethernet networks, to increase the capability of

the wireless LAN. For example, home users can connect their DSL or cable modem to a wireless router (access point)

to provide an Internet connection for a wireless-enabled laptop (node).

In addition to IEEE 802.11, there are several other wireless technologies suited for different applications and

industries, such as Bluetooth. This application note discusses only IEEE 802.11 because it is the most widely used and

easiest solution.

Using the GPIB-ENET/100 for Wireless Instrument Control

The NI GPIB-ENET/100 is designed to communicate over any Ethernet-based TCP/IP network. Combining the

GPIB-ENET/100 with any commercially available wireless router, you instantly transform your Ethernet control

system into a wireless instrument control system.

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Summary of Contents

Page 1 - Using the GPIB-ENET/100

Application Note 184National Instruments™and ni.com™are trademarks of National Instruments Corporation. Product and company names mentioned herein are

Page 2 - Performance

Application Note 184 2 ni.comApplicationsApplications for wireless instrument control include the following:• Controlling portable racks of instrument

Page 3

Page 4 - Application Note 184 4 ni.com

Application Note 184 4 ni.comAssigning an IP Address to Your GPIB-ENET/100The primary task in configuring your GPIB-ENET/100 is assigning it an IP add