In-Situ Monitoring systems measure and relay environmental parameters. From a system design perspective such devices represent one node in a network. This paper aims to extend the networking idea from the system level towards the design level. We describe In-Situ Monitoring systems as network of components. In the proposed design these components can be implemented in either hardware or software. Therefore, we need a versatile hardware-software platform to accommodate the particular requirements of a wide range of In-Situ Monitoring systems. The ideal testing ground for such a versatile hardware-software platform are FPGAs (Field Programmable Gate Arrays) with embedded CPUs. The CPUs execute software processes which represent software components. The FPGA part can be used to implement hardware components in the form of hardware processes and it can be used to interface to other hardware components external to the processor. In effect this setup constitutes a network of communicating sequential processes within a chip. This paper presents a design flow based on the theory of CSP. The idea behind this design flow is to have a CSP model which is turned into a network of hardware and software components. With the proposed design flow we have extended the networking aspect of sensor networks towards the system design level. This allows us to treat In-Situ Measurement systems as sub-networks within a sensor network. Furthermore, the CSP based approach provides abstract models of the functionality which can be tested. This yields more reliable system designs.