Concurrent system-level error detection using a watchdog processor

Abstract

This paper describes the design of a watchdog coprocessor for detecting hardware and software errors. The watchdog executes assertions about the process running on the main computer. Both general purpose an special purpose (used to check systems such as digital signal processors, telephone switching systems, or digital flight controllers) watchdog designs are described. The improvement of error coverage by adding control flow checking facilities is discussed. The implementation of the watchdog as a software process is presented.