leftshift.vst

来自「i need of vhdl code for 32-bit risc proc」· VST 代码 · 共 43 行

ENTITY leftshift IS
PORT (
inpbit1 : IN bit;
inpvec1 : IN bit_vector(4 downto 0);
shresult1 : OUT bit_vector(4 downto 0)
);
END leftshift;

ARCHITECTURE leftshift_arch OF leftshift IS

COMPONENT mux2to1
PORT (
inp1 : IN BIT;
inp2 : IN BIT;
en : IN BIT;
outp : OUT BIT
);
END COMPONENT;

COMPONENT buffer1
PORT (
bu1 : IN BIT;
bu2 : OUT BIT
);
END COMPONENT;

SIGNAL selection1 : BIT;

begin

buffer11 : buffer1 PORT MAP(inpvec1(4),selection1);

mux1 : mux2to1 PORT MAP(inpbit1,inpvec1(3),selection1,shresult1(4));

mux2 : mux2to1 PORT MAP(inpvec1(4),inpvec1(2),selection1,shresult1(3));

mux3 : mux2to1 PORT MAP(inpvec1(3),inpvec1(1),selection1,shresult1(2));

mux4 : mux2to1 PORT MAP(inpvec1(2),inpvec1(0),selection1,shresult1(1));

mux5 : mux2to1 PORT MAP(inpvec1(1),inpbit1,selection1,shresult1(0));

end;