Download FPSCALC Version 2.00 User's Manual

2 Functional Description of the FPSCALC Program
The FPSCALC program takes input from a user specied le, which should be
organised as follows:
One or more task sets.
Each task set's relevant variables and (optional) their initial values.
Each task set's set of formulas to be used for calculation.
Optionally, extra data concerning semaphores, used to calculate the blocking factors for each task set.
2.1 Description of the Input File Grammar
The input le can describe one or more systems. Each system is represented by
a set of variables and the formulae that compute these variables.
The input le is a text le that should should conform to the following grammar
given in appendix A.
System names, variable names, semaphore names and task names do not conict with each other. However the names should be anything other than the
reserved words, including the two reserved indices: i and j. The former is reserved to indicate the main index while the latter indicates the secondary index.
When used in a formula, the main index species that the calculation should
be performed for each task of the task set. The secondary index j is used inside
a summation only, indexing tasks of the task set according to the used priority
scheme. This will be explained in detail later on in this document.
The order in which the system blocks are placed is of no importance. Comments
are preceded by the `!' character. When this character is found on a line,
everything following it on this line will be ignored.
Within each system, the following blocks can be placed:
A declarations block.
A semaphores block.
An initialise block.
A formulas block.
How these blocks are declared, is described in the following sections.
2.1.1 The declarations Block
Within the declarations block, the following symbols can be declared: