AN/UYK-43

The AN/UYK-43 was the standard 32-bit computer of the United States Navy for surface ship and submarine platforms, starting in 1984. Some 1250 units had been delivered through 2000. The size of a refrigerator, it replaced the older AN/UYK-7, both built by UNISYS and shared the same instruction set. An enhancement to the UYK-43, the Open Systems Module (OSM), allows up to six VMEbus Type 6U commercial off-the-shelf (COTS) cards to be installed in a UYK-43 enclosure.

The UYK-43 is being replaced by the AN/UYQ-70 and commercial off-the-shelf systems. Retired systems are being cannibalized for repair parts to support systems still in use by U.S. and non-U.S. forces.

Architecture
The historic AN/UYK-43 architecture includes active redundancy. It include multiple processors, multiple memory banks, and multiple input-output devices with interfaces for multiple disk drives. Power-on self test firmware incorporates features that reconfigure software loading in order to bypass failure. This allows it to run in degraded mode with failed processors, failed memory, failed disk drives, and failed input/output devices. Remote status boards perform fault reporting.

These features improve combat survivability and eliminate requirements for periodic diagnostic maintenance, which is the intent of condition-based maintenance.

The standardized computer programming language associated with UYK and AYK series computers is called CMS-2 developed by Rand Corporation.