The goal of this work was to design a multifunctional data logging unit capable of logging and displaying data from a various busses. In the first chapter this unit is described in detail along with associated problems. In the second chapter a brief survey of commercial products and a comparison of its parameters is being done. In part number three theoretical problems are covered. In the next part more detailed concept of the data logger is described followed by a mechanical construction of the unit. Chapter six describes electrical part of this work. Chapter number seven covers software part of this work. Final chapter consists of a multiple unit tests. In conclusion results are evaluated and possible future improvements are discussed.