The Rulbus is a simple I/O-bus, independend of the bus of the microprocessor used. Bus-specifications are such that all microprocessor types can be connected to the Rulbus via a simple Rulbus-interface. Thus a single version of an I/O-card can be used with various types of microprocessors and microcomputer systems.
Besides independency of the computer, an important aspect is the quietness of the bus: when there is no bus activity, the I/O-signals are still.
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