Embedded software development approaches used models of computation such as dataflow, discrete events, synchronous/reactive, among others. Due to the specialization of the existing models, each one can be better applied to a specific application domain. Nevertheless, when there is no solution for applications in a specific domain, heterogeneous models have been used. In this context, this paper discusses a heterogeneous model called Extended Dataflow. It is an extension of the dataflow model with support to event handling. This paper also addresses how software can be synthesized from extended dataflow specifications and discusses the development of a code generation tool prototype. This takes into account the possibility of component reuse for developing digital signal processing applications. A case study of adaptative applications using digital filters is used to illustrate our approach.