Onyx Advert - August 1981

Onyx was formed in December 1978 by two former Zilog employees, Robert Marsh and Kip Myers, with some additional input from fellow former Zilog employee Doug Broiles, who had left the CPU company to join Winchester disk manufacturer IMI.

Onyx's founders had left Zilog following a management shake up and decided to start the new company because they "liked the idea of selling a packaged microsystem for small businesses", but they also wanted that system to be based on a 16-bit processor, aimed higher at the higher end of the market^[1].

When the company first started shipping products in April 1979, there weren't any readily-available 16-bit processors around, and so the its first product was based on their former company's 8-bit Z80 processor.

This micro - initially called the C8000 - found some early success when the company won a contract to supply 600 machines to Telema, which exported them into Europe.

Although the C8000 became the first microcomputer to use an 8" Winchester disk drive^[2], thanks to Doug Broiles's IMI connection, the machine the company really wanted to produce was waiting upon Zilog's Z8000 processor, which the chip company was promising would be widely available by the January of 1980.

Onyx's eventual 16-bit machine - the C8002 - started shipping around April of 1980. It was essentially a C8001, but came with plug-in board hosting the Z8000, which was also made available as an upgrade to existing C8001 users. Co-founder Marsh said:

"When [Zilog's Z8000] does become available in the quantities we need, we'll just plug in the Z8000 board as an upgrade, keeping the Z80 in the system to handle disk and tape. The RAM will be used as a cache for tape or disk"

The C8002 shipped with Western Digital's version of Unix, which supported up to eight users. This made Onyx one of the very first sellers of a microcomputer-based Unix system.

Meanwhile, the older C8001 was available with a multi-user version of Oasis, called Moasis, as well as CP/M and Pascal.

The original C8000 (later C8001) retailed for $12,500 - that's about £60,300 in 2025 terms.

Onyx eventually merged with its Winchester disk supplier IMI Systems Incorporated to become Onyx+IMI Inc. This company was in turn merged into Corvus, a company famous for its Omninet networking system, in 1985^[3].

Unfortunately, by 1987 Corvus was in serious financial difficulty, largely caused by its lateness in adapting to the rise of the IBM PC. Its then-president Jim Seile ended up shutting down Onyx and selling off its remaining inventory. Rights to a couple of Onyx's product lines were also sold^[4].

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Sun Microsystems' founder Scott McNealy worked for Onyx in 1982, before leaving to found the more-famous Unix workstation company Sun, along with Vinod Khosla, Andy Bechstolsheim and Bill Joy^[5]