Recent trends in field bus applications, especially in the automotive section, show a very high demand for data exchange between decentralised, intelligent functional units and modules. These functional units can be grouped together to power train applications or body/convenience applications.In many cases, the coupling of local modules is done with one or more independent bus systems. The actual design and the partitioning of the modules strongly depend on application-specific requirements, such as the total amount of data to be transferred or the maximum of the tolerated latency in data delivery.A very powerful and fast field bus is the CAN bus (Controller Area Network), which supports transfers with data rates up to 1 Mbits/s. Due to the higher transmission speed and the standardized functionality, CAN is a very interesting alternative to and improvement on bus systems based on other protocols.In order to meet the specific requirements of the large variety of applications, the CAN module's internal structure has to have wide ranging flexibility as well as be adapted to this special communication task. An optimised integrated device, such as the Infineon TwinCAN module, can be seen as a cheap and efficient solution. Microcontrollers with integrated peripherals supporting the CAN protocol can be found on the market from most semiconductor manufacturers.