Protecting pipelined asynchronous communication channels against single event upsets

Abstract

This paper proposes a new solution for building robust asynchronous communication links for globally asynchronous locally synchronous (GALS) systems. A combination of delay-insensitive codes and error-correcting codes is used to provide both robustness against timing variations and against transient faults due to radiation effects or electromagnetic interference. The proposed solution is able to handle short erroneous signal transitions as well as soft-errors, where a faulty value is stored, e.g., in a memory element of a pipelined interconnect architecture. Transient pulses, which sooner or later vanish, can be easily detected and mitigated. In the presence of soft-errors, however, error correction gets significantly more complex since it can no longer be assumed that all expected signal transitions will eventually occur. An on-going transmission thus might never achieve full completeness. This needs to be carefully considered for the receiver design.