1980 Microsoft Announces XENIX OS Microsoft announces Microsoft XENIX OS, a portable operating system for 16-bit microprocessors. It is an interactive, multi-user, multi-tasking system that will run on Intel 8086, Zilog Z8000, Motorola M68000, and DEC PDP-11 series. All of Microsoft's existing system software (COBOL, PASCAL, BASIC and DBMS) will be adapted to run under the XENIX system, and all existing software written for UNIX OS will be compatible as well. ? 1998 Microsoft Corporation. All Rights Reserved.