SIMH is a highly portable, multi-system simulator.

SIMH implements simulators for:
 - Data General Nova, Eclipse
 - Digital Equipment Corporation PDP-1, PDP-4, PDP-7, PDP-8, PDP-9,
      PDP-10, PDP-11, PDP-15, VAX
 - GRI Corporation GRI-909
 - IBM 1401, 1620, 1130, System 3
 - Interdata (Perkin-Elmer) 16b and 32b systems
 - Hewlett-Packard 2116, 2100, 21MX
 - Honeywell H316/H516
 - MITS Altair 8800, with both 8080 and Z80
 - Royal-Mcbee LGP-30, LGP-21
 - Scientific Data Systems SDS 940

These simulators are capable of running the Unix V5, V6 and V7 binaries
licenced for non-commercial use by SCO.  See documentation for further details.