Abstract-Embedded systems are becoming increasingly ubiquitous, controlling a wide variety of popular and safetycritical devices. Effective testing techniques could improve the dependability of these systems. In prior work we presented an approach for testing embedded systems, focusing on embedded system applications and the tasks that comprise them. In this work we focus on a second but equally important aspect of testing embedded systems; namely, the need to provide observability of system behavior sufficient to allow engineers to detect failures. We present several property-based oracles that can be instantiated in embedded systems through program analysis and instrumentation, and can detect failures for which simple output-based oracles are inadequate. An empirical study of our approach shows that it can be effective.