Control software plays an important role in industrial automation. Several domainspecific languages for control software implementation were designed and accepted in industry. Structured Text (ST)[1] is one of these languages. It is standardized by IEC 61131-3 standard and designed for programmable logic controllers. In this thesis two implementations of control software were developed: Java implementation as a reference model, and ST implementation as a test scenario for ST to C compiler. The functionality of both implementations was compared using the simulation model. It was concluded that resulting ST control software provides the same functionality as its reference model.