GPIB

With the development of computer technology and microprocessor based instrumentation, the GPIB standard was adopted by the Institute for Electrical and Electronic Engineers (IEEE) and is currently supported by many instrument manufacturers. It was originally developed by Hewlett-Packard, and was called the HPIB (Hewlett-Packard Interface Bus). It is now widely known as GPIB (General Purpose Interface Bus). This system is comprised of functional (e.g. signal conditioning instruments), electrical (e.g. oscilloscopes and multimeters) and mechanical (e.g. motion control system) elements connected to an interface complying with the IEEE-488 standard.

The GPIB system is a parallel communication system, which can communicate with several devices through the same interface port. The devices that are connected to this bus fall into three categories: controller, listener and talker, all of which are connected through the IEEE-488 connector, as shown below.

IEEE-488 Connector

The structure of the IEEE-488 bus lines, with the automated test system of the quasi-optical frequency multiplier grid array as an example, is shown in the figure below.

IEEE-488 is a bidirectional parallel interface with special control signals. For the PCI-GPIB, the data transfer speed is typically 1 Mbytes/s (limited by the speed of the slowest listener). This data capacity includes all necessary handshaking. The data transfer speed largely depends on the configuration of the system. The stackable connectors and the design of the bus allow a single computer interface card to be used to connect to as many as 15 instruments in a star or linear configuration, as shown below.

Linear (a) and star (b) system configurations

Last Modified: September 8th, 2000 Send Comments to: Weiying Li