SDF-Domain (Synchronous Data Flow)

The SDF domain is a data driven, statically scheduled domain in MLDesigner. It is used to model time discrete systems, as for example digital signal processing, general or special purpose processors. In this domain model elements exchange synchronously a fixed quantity of data elements, so called particles. "Statically scheduled" means that the firing order of the primitives is determined once during the start up phase on the basis of fixed generating and consuming rates of the data elements. Within the SDF domain time does not exists. Another data driven domain is the DDF Domain (Dynamic Data Flow). Whereas in the SDF domain the generating and consuming rates are fixed, the rates in the DDF domain are variable, which allows a dynamical change of the data processing.

DE-Domain (Discrete Event)

The discrete event (DE) domain in MLDesigner provides a general environment for event-oriented simulations of systems such as queuing networks, communication networks, and high-level models of computer architectures, organizational systems, or production systems. In this domain, each Particle represents a time-event that corresponds to a change of the system state. The data exchange itself represents an event appearing at one part of the model and acting on another model element. The DE domain schedulers process events in chronological order. Since the time interval between events is generally not fixed, each particle has an associated time stamp. Time stamps are generated by the block producing the particle based on the time stamps of the input particles and the latency of the block. Features like special events or resources, which represents the use of quantities and processor computation times, make modeling intuitive. The use of ready-made model elements like scheduling mechanism simplifies significantly the modeling process. The DE domain allows the modeling of a multitude of systems, such as bus systems, digital controller systems, computer architecture and system-on-a-chip (SoCs), networked computer systems, or networked organizational, production, or design/development processes.

FSM-Domain (Finite State Machine)

FSM is a concept for modeling event based systems with finite state automatons, an abstraction where the system behavior is represented by directed graphs, a finite set of conditions, called states, and transitions between this states. The FSM represents the current state of the system or of a part of the system. An event leads to a certain action and to a change of the state. The FSM domain is an alternative concept to model event oriented systems. Internal the FSM models are mapped on DE models. With the FSM domain systems can easily be modeled by one or multiple state automatons. Examples are protocol automatons in data networks, control logic, or general software logic. The MLDesigner FSM domain includes a graphical editor and an action language for defining and managing states, transitions and 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.