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Abstract This paper describes the development of a modeling and design environment for teaching the concepts of performance modeling of hardware/software systems to senior computer engineering undergraduate students. This environment is being developed to support senior capstone design projects in computer engineering. Portions of this environment are currently being beta tested and educational material, including lecture slides and laboratory exercises based on the use of the environment, are being developed. Introduction In spite of the tremendous growth in the use of computers, both in the home and in business, sales of microprocessors and other digital system components for use in desk-top systems accounts for less than 20% of the total sales. The remainder of these components are sold for use in embedded systems. An embedded system is a computer that is part of a larger system and often functions as the main controller for the system. Examples of embedded systems include the engine, environmental, and ABS brake computers in automobiles, flight control and avionics computers in aircraft, and even control systems for high-end home appliances. A key aspect of embedded systems is that they typically require the operation of numerous individual functions to complete their overall application and some of these functions may be performed either in software executing on a microprocessor or on dedicated hardware designed specifically to perform the needed function. During the design process, the designer must decide which functions are to be implemented in software and which are to be implemented in hardware. In addition, embedded systems must be designed to meet constraints not only in terms of performance, but also in terms of cost, weight, power, area, and many other factors. In the design of embedded systems, numerous design alternatives must be considered in the design process. Each potential system architecture must be analyzed to determine its characteristics in terms of the system specifications for performance, cost, power consumption, etc. The designer of an embedded system must analyze the different candidate system architectures and select the best alternative before the detailed design phase begins. Design alternatives must be quickly and accurately evaluated early in the design process before a great deal of detailed information about the system or its components exists. This analysis is most often performed by simulating abstract models of the system architecture in a process known as performance modeling. In the context of this discussion, performance means the capacity of the system as measured by such metrics as throughput, latency, and utilization, which are the key issues in the design of embedded systems. All of the other metrics must ultimately be traded off in terms of performance. The use of performance modeling allows the design space to be more thoroughly explored early in the design process yielding higher quality and lower cost designs. Furthermore, once the system architecture has been selected, if the performance modeling tool is integrated into the design environment, the system-level model can be refined into an actual implementation in an systematic manner. While most computer engineering programs contain a significant amount of material on the basic techniques necessary to implement complex hardware/software systems, such as interrupts, microprocessor bus structures and interfacing, and software design, unfortunately, the use of performance modeling to analyze design alternatives for hardware/software systems has not made its way into the undergraduate curriculum for computer engineering, where embedded systems designers are trained. This paper describes aspects of a project that has the overall goal of helping educators incorporate issues in the design of hardware/software embedded systems, and specifically performance modeling, into their computer engineering curriculum. In order to achieve this overall objective, the project was designed with three specific goals, which were to: l develop an easy-to-use, freely available performance modeling tool that students can use to examine the effects of architectural trade-offs in the design of embedded hardware/ software systems, l develop a library of hardware/software communications mechanisms so that students can concentrate on developing the most effective architecture for their senior capstone design projects, and, l develop educational material in the form of lecture slides, notes, and laboratory exercises, to assist educators in presenting the processes of performance modeling, hardware/software codesign and partitioning, and architectural selection. The remainder of the paper is divided into six sections. Section 2 describes the overall architecture of the proposed design environment. Section 3 describes the abstract performance modeling tool that is part of the environment, and section 4 describes the hardware/software communications library that is used to develop the actual implementations. Section 5 describes the hardware/software platform that students are currently using as a target for their system implementations. Section 6 describes one of the example capstone projects being developed using this environment, and finally, section 7 presents some conclusions and future work. Description of the Modeling and Design Environment The overall structure of the performance modeling and design environment is shown in A PERFORMANCE MODELING AND DESIGN ENVIRONMENT FOR SENIOR COMPUTER ENGINEERING UNDERGRADUATE