The Research And Development Of Embedded Systems Based On Simics Full System Simulation Environment

Features and functions of embedded systems become increasingly diversifiedand connections between systems via bus, backplane and network communicationsbecome increasingly complex, which lead to relative difficulties in debugging,integration and testing of embedded operating systems. In addition, the lack ofhardware reference boards and other physical devices often limits the developmentefficiency of embedded software developers. For example, it’s very difficult forsystem software developers to develop hardware-based software before thedevelopment boards are available; when the number of development board is limited,there is no guarantee that every system developer can obtain one development boardfor software development and designs. Due to the limitations of traditionaldevelopment tools and processes, it is difficult to find embedded systems internallytarget hardware platform-related errors in the development process. The uncertaintyand unpredictability of physical hardware may cause errors in the embeddedapplication software without obvious reasons or warnings.Simics, a full system simulator introduced by Wind River Systems, can provideinnovative features which can’t be achieved by physical hardware. This simulatorcan help developers solve the above problems. First, Simics provides a powerfulvirtual platform which can simulate processors, memory, board-level hardware,complex network systems and other hardware target devices in any sizes. The virtualplatform can help software developers to solve the problems caused by lack ofhardware. Binary code running on Simics simulated hardware platform can run onthe target device without making any changes. Second, Simics enables hardware andsoftware fault injection, virtual system time control and management of hardwareregisters. It also supports accurate and repeatable forward and reverse single stepexecution of the entire system, as well as the creating checkpoints and snapshots.Embedded software developers can use Simics to achieve a unique way ofdevelopment and debugging, such as starting or pausing clocks of both operatingsystems and processors, checking the status of all system components, non-invasivefault injection.As one real-time operating system, VxWorks has been widely used in theindustry because of its quick real-time response, high stability and reducible and configurable characteristics. VxWorks operating system has been applied in thedefense, aerospace, consumer electronics, automotive navigation and many otherfields. Compared with VxWorks5.x, VxWorks6.x has many improvements, such asthe introduction of the RTP real-time process and support for virtual addressmapping. These improvements further enhance the leading position of VxWorks inthe industry of real-time operating systems.This paper discusses the development and research of VxWorks6.9embeddedsystem’s bootrom, device drivers, BSP and applications, as well as customization ofVxWorks6.9operating system under Simics full system simulation environment.Finally, the methodology of using Simics to develop underlying software,middle-layer software and upper-layer software of VxWorks is explored andsummarized.