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Reference Section
terface and executing principles that are similar to a Simulator. The
technical approach is however different; a Validator is based on a technique called state space exploration and operates on structures called
behavior trees. Its purpose is to validate an SDL system in order to find
errors and to verify its consistency against Message Sequence Charts.
Reference Section
Representation of Signals and Processes
In this first section, the representation of signals and processes is presented. The symbol table, which is a representation of the static structure of the system, will also be discussed. The information given here
will be used in the next part of this section where the environment functions, which should be provided by the user, are described.
Types Representing Signals
A signal is represented by a C struct containing general information
about the signal followed by the parameters carried by the signal.
Reference
to signal
xSignalNode Pre
xSignalNode Suc
SDL_PId
Receiver
SDL_PId
Sender
xIdNode
NameNode
int
Prio
first signal parameter
second signal parameter
Figure 491: Data structure representing a signal
A general typedef xSignalRec for a signal without parameters and for
a pointer to such a signal, xSignalNode, are given below. These types
may be found in the file scttypes.h. These types may be used for type
casting of any signal to access the general components.
typedef struct xSignalRec *xSignalNode;
typedef struct xSignalRec {
xSignalNode Pre;
xSignalNode Suc;
SDL_PId
Receiver;
SDL_PId
Sender;
xIdNode
NameNode;
July 2003
Telelogic Tau 4.5 User’s Manual
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