Choosing the Interface for Your Instrument

You may have a choice of several different physical interfaces with which to connect your instrument to your computer. This topic will give you some guidelines to help with that decision. If you are constructing a large or complex test system, or if your test system will be used for a long time, you will want to make this decision carefully.

First, determine the interfaces that are available to you on each side of the connection (instrument and computer). Not all interfaces are available on all instruments. Computers typically have USB, LAN, and a limited number of serial (RS-232) interfaces available, but require the addition of an interface card (such as the Keysight 82350B PCI GPIB Card) to support GPIB.

Adaptor products are available to connect a computer to GPIB instruments using either the computer's USB interface (Keysight 82357B USB/GPIB Interface Converter) or its LAN interface (Keysight E5810B LAN/GPIB/USB Gateway). These products provide convenient and powerful ways for you to take advantage of computer-standard IO with a large range of instruments.

Connecting Instruments via LAN

A local area network (LAN, also known as Ethernet) provides instrument connectivity over distances and allows sharing of instruments among multiple users and multiple computers. Ethernet LANs are almost universally available; they support data rates of 10 MB/second to 1 GB/second and they use inexpensive cables and connectors. Many instruments have LAN interfaces built in. For those that do not, you can use the Keysight E5810B LAN/GPIB/USB Gateway). LAN is a recommended method to connect instruments together in applications such as new test systems.

You can connect your instruments to a private LAN or to a site LAN.

A private LAN is set up specifically for your use in connecting your instruments. Typically, you will be the administrator of the private LAN, and you will control connections, cabling, and addressing. Your computer and all instruments are connected via a networking switch or router that isolates them from your site LAN. You can think of a private LAN as just another type of bus for your test system, like GPIB or USB; the private LAN is used only by your test system. You should use a private LAN if you want total control of your network and instruments, or if it is important that your test system achieve maximum throughput.
Your site LAN is the network you use to connect with other computers, printers, and devices in your work group. Your computer is probably already connected to the site LAN; you use the site LAN to connect to your intranet and/or to the Internet. If you want to share instruments with other users, or if you need access to instruments across an intranet or the Internet, you can use your site LAN. You may need to work with your IT department to put your instruments on the site LAN.

When you are connecting a new instrument to your network (private or site LAN), you have several options. Click the links below for more information.

LAN Direct Connection

LAN Connection via Gateway

LAN Connection via Remote IO Server PC

Connecting to PXI Modular Instruments

In order for BenchVue to recognize and communicate with a PXI modular instrument, you must first enable the HiSLIP interface from the instrument's Soft Front Panel (SFP). For more information, see Connecting to PXI Modular Instruments.

Connecting Instruments via USB

The Universal Serial Bus (USB) is a quick and easy way to connect instruments to computers. Some newer instruments have USB interfaces built in. For those that do not, you can use the Keysight 82357B USB/GPIB Interface Converter to establish connectivity easily and inexpensively. You can one USB port to connect a single instrument to a PC; or, via the 82357B, you can connect up to 14 GPIB instruments to one USB port.

Note: If you are using USB to connect to your instruments, make sure you are using USB 2.0 ports. At this time, you might experience connection integrity and performance issues with USB 3.0 (indicated by "SS" next to USB connector on computer).

Connecting Instruments via GPIB

The General Purpose Interface Bus (GPIB) is fast and robust, but requires a special PC card and additional configuration steps. Many existing systems are based on GPIB, and it is the best option for many instruments that have only GPIB and serial connectors.

Connecting Instruments via Serial Port (RS-232)

Serial connection is inexpensive and widely available, but is slow compared to other I/O interfaces, and requires particular attention to cabling and configuration. Instruments connected via serial port are not normally automatically detected by I/O software. Connect your instruments via serial port only if these factors are not a concern for you, or if no other option is available.