VHDL设计十进制计数器

EDA课程设计——清零置数十进制计数器程序清单：libraryieee;useieee.std_logic_1164.all;useieee.std_logic_unsigned.all;entitycdu10isport(clk,en,load,reset:instd_logic;d:instd_logic_vector(3downto0);cout:outstd_logic;q:outstd_logic_vector(3downto0));endcdu10;architectureexx1ofcdu10issignalqq:std_logic_vector(3downto0);beginp0:process(clk,en,load,reset)beginif(reset='0')thenqq=0000;elsif(clk'eventandclk='1')thenifload='0'thenqq=d;elsif(en='1')thenifqq=1001thenqq=0000;elseqq=qq+'1';endif;endif;endif;endprocessp0;q=qq;p1:process(qq)beginifqq=1001thencout='1';elsecout='0';endif;endprocessp1;endexx1;仿真波形：