The mast mounted sight 771 processor upgrade program

Abstract

The 771 microprocessor is used as the main control processor for the Mast Mounted Sight (MMS) on the Bell Helicopter OH-58A helicopter for the US Army Advanced Helicopter Improvement Programme (AHIP). The 771 and its test set/development system were designed in January 1977. These 10-year-old designs currently have a wide range of problems in production, test, and software development. To increase system performance, lower manufacturing costs, and improve software development efforts, an upgraded 771 processor and development system has been developed. The new processor, the 771C, is implemented using ASIC (application-specific integrated circuit) and VLSI technology. The 771C increases memory and I/O capability, reduces board and part counts, and increases throughput by up to 73%. The author describes the 771C and its development system implementation performed at McDonnell Douglas Astronautics Company, Huntington Beach, California.<>