A circuit for sharing peripherals and instruments with the IEEE-488 interface between two or more microcomputers

Abstract

The IEEE-488 bus forms the basis of most automated test systems. Several microcomputers provided with this bus are available cheaply, but the instruments and peripherals may be expensive. Unfortunately, it is a characteristic of the interface standard that there can be only one controller on the bus and hence only one microcomputer can independently access a shared peripheral or instrument on the bus. This paper describes a low-cost circuit that will allow two or more microcomputers to share and independently control peripherals and instruments equipped with the IEEE-488 interface. The circuit does not affect communication between a microcomputer and a peripheral or instrument dedicated to it. © 1986.