Abstract
Rapid-Prototyping of control units within the automotive field of application is frequently done by the employment of simple microcontroller boards. These are proprietary and mostly bound to a concrete vehicle configuration. Besides the connection of IO and bus systems turns out as difficult. Alternatively one can use also expensive universal control units. A more economical alternative are, from the automatic control engineering admitted, Programmable Logic Controllers (PLC). Which usually have a sufficient computing power and various connection types for digital and analog IO. For the integration in the vehicle this contribution describes a configurable CAN interface, which is integrated completely into the PLC world as well and can be programmed with the standard devices.
The configurableness goes far beyond the attitude of default values, as for example the Baud rate. Rather it is possible to map individual bits from different CAN messages on individual bits in the process image of the PLC. Thereby the control program on the PLC is completely decoupled of data existing on the CAN bus, since the messages and their contents are filtered accordingly. The program is model- and producer-independent because it describes an application in an abstract way. The binding to a concrete vehicle is made only by the configuration.
So one can develop for example a universal control unit for the controlling of the electrical window lifters, which is attached to the CAN bus and to the appropriate IO and whose software is always the same whether it is used in an Audi or in a Mercedes.
Keywords: Rapid-Prototyping, CAN, Automation Technology, PLC