Design And Development Of Window Switch For Automobiles Based On LIN Communication

Automobile electronic technology has been gradually recognized by automobile manufacturers thanks to the development of electronic communication technology.Also,the large-scale application of automobile electronic technology has remarkably upgraded key performances such as maneuverability,safety,and comfort of automobiles.Currently,automobile electronic control methods are trending towards network,integration,and modulation.Moreover,the body control module(BCM)plays a vital role in the automobile network.And the automobile window switch must always maintain communication with the BCM in the automobile architecture planning so that its own status can be sent to the BCM in real time.In this paper,the window lifter switch was designed to transfer information with the BCM via the LIN bus.To be specific,the window switch is the slave node,while the BCM is the master node.At first,the basic topology architecture of the window control system was studied based on the CAN/LIN bus.Then,a hardware system was designed and developed for the window switch.On this basis,the software architecture was planned and improved to achieve appropriate coordination between the software and hardware of the window switch module.Moreover,the window switch based on the LIN bus was designed with many expanded functions apart from window glass lifters.What’s more,some expansion ports were reserved in the design of hardware for implementing functional expansions through slightly changing the hardware circuit,and software programming.In addition,the LIN protocol in software design is functioned as controlling and using the physical link layer of the LIN bus with the software design and programming in the LIN driver layer as its core foundation,which can be used through the interface layer,rather than being used directly via the application layer.In terms of the LIN driver layer,LIN＿DATAsend(LIN sending function)and LIN＿DATArecieve(LIN receiving function)were primarily introduced,which was designed with the addition of software expansion on the premise of containing the functions of the traditional window switch.Also,two bits of data were reserved for future expansion during the definition of the LIN data field.Meanwhile,other switches on the door were also connected to the window switches,contributing to significantly expanding the function of the door system.As for the design of hardware and software,high reliability and low cost of development were realized in the window switch.