Hardware/software co-design of communication protocols

An important aspect in providing high performance distributed systems such as multimedia systems is the combined use of hardware and software in the end systems. System design techniques should allow hardware/software co-design to integrate both means of implementation. In this paper we show how the standardized formal language Estelle can be used to facilitate co-design. The system will first be designed in Estelle. At the point in time of final decision on which parts to implement in software and which in hardware, the original specification will be split into several partial specifications. The software parts are translated into C code, while the hardware parts are translated into VHDL code for further analysis and development. We present a tool environment which supports the protocol developer in the design and implementation process. A simple Video-on-Demand example shows the usefulness of the tool environment.