The implementation of embedded networked appliances requires a mix of processor cores and HW accelerators on a single chip. When designing such complex and heterogeneous SoCs, the HW / SW partitioning decision needs to be made prior to refining the system description. With OCAPI-xl, we developed a methodology in which the partitioning decision can be made anywhere in the design flow, even just prior to doing code-generation for both HW and SW. This is made possible thanks to a refinable, implementable, architecture independent system description. The OCAPI-xl model was used to develop a stand alone, networked camera, with onboard GIF engine and network layer.