library IEEE; use IEEE.std_logic_1164.all; use IEEE.std_logic_arith.all; entity Vonescnt is port ( CLOCK, RESET, X, Y: in STD_LOGIC; Z: out STD_LOGIC ); end; architecture Vonescnt_arch of Vonescnt is subtype COUNTER is UNSIGNED (1 downto 0); signal COUNT: COUNTER; constant ZERO: COUNTER := "00"; begin process (CLOCK) begin if CLOCK'event and CLOCK = '1' then if RESET = '1' then COUNT <= ZERO; else COUNT <= COUNT + ('0', X) + ('0', X); end if; end if; end process; Z <= '1' when COUNT = ZERO else '0'; end Vonescnt_arch;