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genpat, A procedural pattern file generator


genpat [-v] [-k] [file]


This software belongs to the ALLIANCE CAD SYSTEM developed by the ASIM team at LIP6 laboratory of Université Pierre et Marie CURIE, in Paris, France.

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Genpat is a set of C fonctions that allows a procedural description of input pattern file for the logic simulator ASIMUT. The Unix genpat command accepts a C file as input and produces a pattern description file as output. The extension ".c" is not to be given. The file generated by genpat is in pat format, so IT IS STRONGLY RECOMMENDED TO SEE pat(5) BEFORE THIS MANUAL.


verbose mode
keeps the executable along with the compilation Makefile after completion


From a user point of view, genpat is a pattern description language using all standard C facilities (include, define, variables, loop, ...). Fonctions provided by genpat are to be used in a given order. Using them in a different order won't crash the system, but will result in execution errors. Here follows the description of the input file.

A pat format file can be divided in two parts : declaration and description part.

The declaration part is the list of inputs, outputs, internal signals and registers. Inputs are to be forced to a certain value and all the others are to be observed during simulation.

The description part is a set of patterns, where each pattern defines the value of inputs and outputs. The pattern number represents actually the absolute time for the simulator.

Similarly, a genpat file can be divided in two parts : declaration and description part. Functions related to the declaration must be called before any function related to the description part.

The first thing you should do in this part is to give the output file's name (see DEF_GENPAT(3)). Then, this part allows you to declare the inputs, the outputs, and internal observing points (see DECLAR(3)). It is also possible to create virtual arraies (see ARRAY(3)).
After all signals are declared, you can begin to define input values which are to be applied to the inputs of the circuit or output values which are to be compare with the values produced during the simulation. (see AFFECT(3)). Genpat describes the stimulus by event : only signal transitions are described. This part also allows you to give instructions to the simulation tool to save the state of the circuit at the end of the simulation. (see SAVE(3)). Last thing you should do in this part is to generate the output file (see SAV_GENPAT(3)).


defines the output file's name.
make the output file be generated
declares inputs, outputs, and the internal observing points.
allows signals of the same type to be groupped in an "virtual array" in order to ease their manipulation
changes the values of registers between two patterns.
assigns a value to a signal, at a given pattern number. This value is kept on the signal until a new value is assigned to the signal.
informs the simulation tool to save the state of the circuit at the end of simulation
gives a label to the current pattern
return the number of the current pattern


#include <stdio.h>
#include "genpat.h"
char *inttostr(entier)
int entier;

char *str;
str = (char *) mbkalloc (32 * sizeof (char));
sprintf (str, "%d",entier);
/* end of the description */

main ()
int i;
int j;
int cur_vect = 0;


/* interface */
DECLAR ("a", ":2", "X", IN, "3 downto 0", "" );
DECLAR ("b", ":2", "X", IN, "3 downto 0", "" );
DECLAR ("s", ":2", "X", OUT, "3 downto 0", "" );
DECLAR ("vdd", ":2", "B", IN, "", "" );
DECLAR ("vss", ":2", "B", IN, "", "" );

LABEL ("adder");
AFFECT ("0", "vdd", "0b1");
AFFECT ("0", "vss", "0b0");

for (i=0; i<16; i++)
for (j=0; j<16; j++)
AFFECT (inttostr(cur_vect), "a", inttostr(i) );
AFFECT (inttostr(cur_vect), "b", inttostr(j) );



Genpat reads the environment variable VH_PATSFX to give the result file an extension.


AFFECT(3), ARRAY(3), DECLAR(3), DEF_GENPAT(3), GETCPAT(3), INIT(3), LABEL(3), SAVE(3), SAV_GENPAT(3), pat(5), asimut(1)


This tool is under development at the ASIM department of the LIP6 laboratory.
We need your feedback to improve documentation and tools.

October 1, 1997 ASIM/LIP6