Switching system for non-symmetrical sharing of computer peripheral equipment

摘要: Switching apparatus and methods are disclosed by which one or more secondary computers of a loosely-coupled multiprocessing system may communicate directly with selected items active peripheral equipment main computer the system. This invention, is an improvement over device-sharing means indirect-accessing prior art, be applied to existing systems without modification any element their hardware operating software computer. An essentially autonomous "intelligent switch," connected input/output interface (bus) each processor completely transparent processor, used switch from in response asynchronous service requests Two modes operation provided: Interface Capture Data Capture. provides for temporarily borrowing having off-line capabilities, such as buffered line-printers, performed during normal equipment. With Capture, requesting obtains complete control captured item arbitrary period time. on other hand, designed use primarily direct-access auxiliary storage devices while device executing read write initiated accessing shared data space without, however, requiring duplicate replicate access-method capabilities Instead, draws parasitically upon resources access requested space. Unlike this accomplished burdening its storage, channels overhead tasks buffering blocks dispatching