Programmable mask macro-generator
#include <genlib.h>
void GENLIB_MACRO (DPGEN_XNOR2MASK, char *modelname, long flags, long N, char *constVal);
Generate a N bits conditionnal XNOR mask named modelname.
How it works :
•
if the cmd signal is set to '0', the mask is NOT applied, so the whole operator behave like an inverter.
•
if the cmd signal is set to '1', the mask IS applied, the output is the complemented result of the input value XORed with the mask (suplied by constVal).
The constant constVal is given to the macro-generator call, therefore the value cannot be changed afterward : it's hard wired in the operator.
A common error is to give a real C constant for the constVal argument. Be aware that it is a character string.
1.
cmd : mask control (1 bit).
2.
i0 : input (N bits).
3.
q : output (N bits).
4.
vdd : power.
5.
vss : ground.
nq <= WITH cmd SELECT not(i0) WHEN '0', not(i0 xor X"0000FFFF") WHEN '1';
GENLIB_MACRO(DPGEN_XNOR2MASK, "model_xnor2mask_0000FFFF_32" , F_BEHAV|F_PLACE , 32 , "0x0000FFFF" /* A string! */ ); GENLIB_LOINS( "model_xnor2mask_0000FFFF_32" , "instance1_xnor2mask_32" , "cmd" , "i0[31:0]" , "q[31:0]" , "vdd", "vss", NULL );