interface elements. The FSM model can be formally validated and code generated from this validated model. CTDE-Domain (Continuous Time/Discrete Event) The CTDE-domain is a further time oriented domain for describing continuous time systems, as analog and mixed-signal devices. The two distinct models of computation, continuous time and discrete event are combined into one domain, in order to permit to models systems that include time-events and state events, like hysteresis. Connections between ports of different types are made possible by inserting a primitive to convert the signal. The description of systems within the CTDE domain corresponds to the description with differential equations. The state derivatives are inputs to integrator blocks, while the derivative equation and the output functions are modeled by networks of primitives that perform arithmetic operations. The CTDE domain includes multiple integration algorithms. MLDesigner contains several more domains, for example the HOF domain (High Order Function), which allows a procedural modeling of systems. The BDF (Boolean Data Flow) domain can be thought as a generalization of the SDF domain. It expands the concept of data flow oriented domains by the possibility to activate or deactivate parts of the model according to combinatorial logic. Code-Generation-Domain Beside the above described domains, which can be used to model and to simulate and therefore are called simulation domains, there are several code generation domains in MLDesigner. For a model created in one of the simulation domain it is possible to change the domain in a code generation domain as long as all the used model elements are in the code generation domain included. It is then possible to create object code in C or VHDL. Beside using MLDesigner code generation domains, it is possible to generate directly ANSI-C Code, VHDL-Code or SystemC-Code for models completely created with elements of the DE and the FSM domain. Application areas The multi-domain simulation environment may be used in early development stages for validation of executable specifications at application/mission level and perform architectural optimization at overall system level. MLDesigner can be used to design missions, systems, integrated circuits, reconfigurable electronics and miscellaneous other products. It can be applied for modeling, simulation and optimization of automotive, avionics and space systems, satellite communication systems and organizational, production, and development processes. See also OMNeT++ QualNet NEST (software) References G. Schorcht, P. Unger, A. George, I. Troxel, D. Zinn, H. Salzwedel, K. Farhangian, C.K. Mick: "System-Level Simulation Modeling with MLDesigner", IEEE