subdesign  control2
(
adda[3..0],addb[3..0],addc[3..0],addd[3..0]:input;
suba[3..0],subb[3..0],subc[3..0],subd[3..0]:input;
muxa[3..0],muxb[3..0],muxc[3..0],muxd[3..0]:input;
diva[3..0],divb[3..0],divc[3..0],divd[3..0]:input;
conl[3..0]:input;
outa[3..0],outb[3..0],outc[3..0],outd[3..0]:output;
)
begin
if  conl[]==B"1010" then
outa[]=adda[];
outb[]=addb[];
outc[]=addc[];
outd[]=addd[];
elsif  conl[]==B"1011" then
outa[]=suba[];
outb[]=subb[];
outc[]=subc[];
outd[]=subd[];
elsif  conl[]==B"1100"  then
outa[]=muxa[];
outb[]=muxb[];
outc[]=muxc[];
outd[]=muxd[];
else
outa[]=diva[];
outb[]=divb[];
outc[]=divc[];
outd[]=divd[];
end if;
end;