Terminology » Measurements » GPIB vs VXI: A Detailed Comparison of Instrument Interfaces

GPIB vs VXI: A Detailed Comparison of Instrument Interfaces

instrument interface gpib vxi data acquisition test equipment

This page outlines the fundamental differences between GPIB (General Purpose Interface Bus) and VXI (VME eXtensions for Instrumentation) interfaces. We’ll also touch on other instrument interfaces for a broader understanding.

GPIB Interface

The GPIB interface is designed to connect computers, instruments, and other peripherals. It’s a versatile interface, carrying both data and control information between connected devices.

To use GPIB, you’ll typically need a GPIB adapter to provide the necessary connectivity. One GPIB interface can handle approximately 14 devices, achieving a maximum data transfer speed of around 200 Kbps. This makes it suitable for applications where distances are relatively short.

VXI Interface

The VXI interface builds upon the VMEbus architecture, offering advantages over GPIB in terms of size and integration. It allows for more compact and integrated systems.

However, as it relies on older PC architecture, VXI doesn’t fully capitalize on the advancements found in modern PC technologies.

SpecificationsGPIBVXI
Width of Bus in bits88/16/32
Data throughput1 OR 8 Mbytes/secondMax. 160 Mbytes/second
SynchronizationNot requiredDefined in the specifications
SizeLargeMedium
Software frameworkNot neededVXI plug and play
ModularityNot supportedSupported
EMI shieldOptionalDefined in the spec. (All modules need metal shield)
Cost of the systemHigherMedium to High