Elxsi

Elxsi Corporation was a minicomputer manufacturing company established in the late 1970s in Silicon Valley, US, along with a host of competitors (Trilogy Systems, Sequent, Convex Computer). The Elxsi processor was an Emitter Coupled Logic (ECL) design that featured a 50-nanosecond clock, a 25-nanosecond back panel bus, IEEE floating-point arithmetic and a 64-bit architecture. It allowed multiple processors to communicate over a common bus called the Gigabus, believed to be the first company to do so. The operating system was a message-based operating system called EMBOS. The Elxsi CPU was a microcoded design, allowing custom instructions to be coded into microcode.