Highly integrated real-time requirements of embedded processor systems in recent years have complicated software and hardware debugging, making the impact of debugging tools and methods on debugging efficiency more significant. This paper proposes an embedded processor debugging model, defining the concepts of debugging observability and controllability. By configuring and adjusting observation sets and control sets via debugging tools, the intersection of the observation set with the bug region reveals the presence of bugs, and the intersection with the bug birth point helps identify the root cause. Based on the processor’s spatiotemporal state diagram, the characteristics of debugging tools and fundamental impact on the debugging process are discussed in detail. This research clearly explains debugging principles and their complexity, providing effective theoretical support for debugging and fault localization in embedded systems, with significant implications for both theoretical research and industrial debugging tools.