The increasing deployment of embedded computing platforms in safety-critical domains such as aerospace, automotive electronics, industrial automation, and space systems has intensified the demand for robust fault-tolerant architectures capable of ensuring dependable operation under harsh and unpredictable conditions. Advances in semiconductor technologies, while enabling higher performance and energy efficiency, have simultaneously increased system susceptibility to transient, intermittent, and permanent faults. This challenge is particularly pronounced in reconfigurable and multicore systems, where complexity, concurrency, and resource sharing exacerbate fault propagation and error correlation. This article presents an extensive, theoretically grounded examination of architectural and system-level fault tolerance strategies for embedded processors, with particular emphasis on lockstep execution, dynamic reconfiguration, and FPGA-based softcore designs. Drawing strictly from established scholarly literature, the paper synthesizes foundational dependability concepts, explores classical and modern fault models, and critically analyzes state-of-the-art mitigation techniques, including loosely coupled and tightly coupled lockstep architectures, dynamic binary translation, hardware-assisted partitioning, and reconfigurable redundancy mechanisms. The methodological discussion focuses on architectural design principles rather than empirical experimentation, emphasizing descriptive analysis and conceptual evaluation. Results are presented in terms of observed design trade-offs, reliability implications, and operational constraints derived from prior implementations. The discussion section situates these findings within broader dependability theory, addressing common-mode failures, overhead limitations, and certification challenges, while also outlining future research directions in adaptive fault tolerance and mixed-criticality systems. By providing a deeply elaborated and cohesive narrative, this work contributes a comprehensive reference framework for researchers and system architects engaged in the design of dependable embedded computing platforms.

Fault tolerance, Lockstep architectures, Reconfigurable processors, Embedded systems dependability

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