Fault tolerance for uniprocessor systems

Fault tolerance for system architectures is typically associated with multiple levels of redundancy, common examples are duplex, triplex, and quadruplex. Such system architectures are sometimes referred to as NMR (N-Modular Redundancy). Duplex systems can identify the module in error and switch to continue processing on the standby module. NMR systems, mask errant modules. Whilst these architectures offer very high reliability, their application also incurs in excess of 100% redundancy. The associated cost of this overhead may be significant and perhaps unacceptable for low budget systems. In such situations a uniprocessor fault tolerant approach may be appropriate. The author considers this approach and various capability checks