Technological Obsolescence
With the release of the Notice 4 revision to the standard on July 31, 1996, MIL-STD-1750A was declared inactive for new military projects in the USA. However, both the Indian Space Research Organisation (ISRO) and the Chinese aerospace industry continue to use the 1750 for new projects.
To necessarily say the CPU is technologically defunct can be nebulous. This CPU can run at 0.5 MIPS to 3 MIPS depending on the operating speed (from 1 MHz to 20 MHz). The lack of modern floating point capabilities makes this CPU less suitable for some (but not all) modern embedded applications. However, lack of familiarity (and modern compiler support) with this CPU makes its uptake in the civilian computing sector difficult.
More modern CPUs like the Mongoose-V (used on the New Horizons spacecraft) and the higher performance RAD750 that are both based on more modern computer architectures are replacing the MIL-STD-1750A in the space sector over time. It is expected that by 2030 this CPU's use in aerospace may cease.
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