The GPIB or IEEE 488 interface is a short range parallel bus used for interconnecting devices. It was developed by Hewlett-Packard in the late 1960s for connecting automatic test equipment. It was adopted by the Commodore PET (with a non-standard card edge connector) as a way of connecting peripherals. There are more modern alternatives now, but it is still used on some test equipment.
This board was designed (and built?) by EV Computing Ltd. and was sold under the model number EV814 by Gemini.
The blue connector is the GPIB port, which is a 24-pin Amphenol port – looking rather like a shortened Centronics printer connector. Plugs were often made to “piggy-back” so that the bus could be daisy-chained.
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