GPIB: Advantages and Disadvantages

This page covers the advantages and disadvantages of GPIB (General Purpose Interface Bus). The GPIB IEEE-488 interface bus consists of 8-bit parallel lines. The GPIB connector has a total of 24 pins. It utilizes 16 signal lines, comprising 8 data lines (bi-directional), 3 handshake lines, and 5 for bus management. Additionally, there are 8 ground (GND) lines.

Figure 1: GPIB IEEE-488 connectors in plug and jack configurations.

The GPIB bus employs a 5-bit address, providing a total of 31 possible addresses for use by equipment on the GPIB interface. The IEEE standard permits approximately 15 devices to share a GPIB bus over a length of 20 meters.

Advantages of GPIB

The following are the advantages of using GPIB:

• GPIB interface is simple.
• GPIB interface port is widely available on all test and measurement equipment.
• The GPIB cable uses very rugged and robust connectors.
• Using the GPIB interface, a single controller can monitor and control multiple test and measurement equipment or instruments. This is illustrated in Figure 2, showing two different configurations: linear and star.

Figure 2: GPIB in linear and star connections.

Disadvantages of GPIB

The following are the disadvantages of using GPIB:

• The GPIB connectors are bulky.
• The interface provides low bandwidth data transfer.
• The GPIB interface is used for low-speed data communication, unlike modern interfaces designed for high-speed communication.
• Modern instruments have gradually discontinued its use. It is likely to become obsolete in a few years.