Embedded Software for SoC - Grupo de Mecatrônica EESC/USP

Chapter 4
DETECTING SOFT ERRORS BY A PURELY
SOFTWARE APPROACH: METHOD‚ TOOLS
AND EXPERIMENTAL RESULTS
B. Nicolescu and R. Velazco
TIMA Laboratory‚ “Circuit Qualification” Research Group‚ 46‚ Av. Félix Viallet‚ 38031‚
Grenoble‚ France
Abstract. A software technique allowing soft errors detection occurring in processor-based
digital architectures is described. The detection mechanism is based on a set of rules allowing
the transformation of the target application into a new one‚ having the same functionality but
being able to identify bit-flips arising in memory areas as well as those perturbing the processor’s
internal registers. Experimental results‚ issued from both fault injection sessions and preliminary
radiation test campaigns performed in a complex digital signal processor; provide
objective figures about the efficiency of the proposed error detection technique.
Key words: bit flips‚ SEU‚ SET‚ detection efficiency‚ error rate
1. INTRODUCTION
Technological progress achieved in the microelectronics technology has as a
consequence the increasing sensitivity to effects of the environment (i.e.
radiation‚ EMC). Particularly‚ processors operating in space environment are
subject to different radiation phenomena‚ whose effects can be permanent or
transient [1]. This paper strictly focuses on the transient effects‚ also called
SEUs (Single Event Upsets) occurring as the consequence of the impact of
charged particles with sensitive areas of integrated circuits. The SEUs are
responsible for the modification of memory cells content‚ with consequences
ranging from erroneous results to system control problem. The consequences
of the SEUs depend on both the nature of the perturbed information and the
bit-flips occurrence instants.
For complex processor architectures‚ the sensitivity to SEUs is strongly
related to the amount of internal memory cells (registers‚ internal memory).
Moreover‚ it is expected that future deep submicron circuits operating at very
high frequencies will be also subject to transient errors in combinational parts‚
as a result of the impact of a charged particle. This phenomenon‚ so-called
SET (Single Event Transient) could constitute a serious source of errors not
only for circuits operating in space‚ but also for digital equipment operating
in the Earth’s atmosphere at high altitudes (avionics) and even at ground level
[2]. In the new areas where computer-based dependable systems are currently
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A Jerraya et al. (eds.)‚ Embedded Software for SOC‚ 39–50‚ 2003.
© 2003 Kluwer Academic Publishers. Printed in the Netherlands.