我已经为4位七段显示器编写了代码，并且我试图对其进行修改以驱动nexys 4 ddr的七段显示器上的所有8位数字。
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity eAfisareDistanta is
Port (
digit0: in std_logic_vector(7 downto 0);
digit1: in std_logic_vector(7 downto 0);
digit2: in std_logic_vector(7 downto 0);
digit3: in std_logic_vector(7 downto 0);
digit4: in std_logic_vector(7 downto 0);
digit5: in std_logic_vector(7 downto 0);
digit6: in std_logic_vector(7 downto 0);
digit7: in std_logic_vector(7 downto 0);
clk: in std_logic;
cat: out std_logic_vector(6 downto 0);
an: out std_logic_vector(7 downto 0));
end eAfisareDistanta;
architecture aAfisareDistanta of eAfisareDistanta is
signal i0: std_logic_vector(7 downto 0):="1110";
signal i1: std_logic_vector(7 downto 0):="1101";
signal i2: std_logic_vector(7 downto 0):="1011";
signal i3: std_logic_vector(7 downto 0):="0111";
signal i4: std_logic_vector(7 downto 0):="0111";
signal i5: std_logic_vector(7 downto 0):="0111";
signal i6: std_logic_vector(7 downto 0):="0111";
signal i7: std_logic_vector(7 downto 0):="0111";
signal count: std_logic_vector(15 downto 0):=x"0000";
signal m1: std_logic_vector(7 downto 0);
begin
process(clk)
begin
if rising_edge(clk) then
count <= count +1;
end if;
end process;
process(digit0, digit1, digit2, digit3, count(15 downto 14))
begin
case count(15 downto 14) is
when "00" => m1 <= digit0;
when "01" => m1 <= digit1;
when "10" => m1 <= digit2;
when others => m1<=digit3;
end case;
end process;
process(i0, i1,i2,i3, count(15 downto 14))
begin
case count(15 downto 14) is
when "00" => an<=i0;
when "01" => an<=i1;
when "10" => an<=i2;
when others => an<=i3;
end case;
end process;
process(m1)
begin
case m1 is
when "0000" => cat <= "1000000"; --0
when "0001" => cat <= "1111001"; --1
when "0010" => cat <= "0100100"; --2
when "0011" => cat <= "0110000"; --3
when "0100" => cat <= "0011001"; --4
when "0101" => cat <= "0010010"; --5
when "0110" => cat <= "0000010"; --6
when "0111" => cat <= "1111000"; --7
when "1000" => cat <= "0000000"; --8
when "1001" => cat <= "0010000"; --9
when "1010" => cat <= "0001000"; --A
when "1011" => cat <= "0000011"; --b
when "1100" => cat <= "1000110"; --C
when "1101" => cat <= "0100001"; --d
when "1110" => cat <= "0000110"; --E
when others => cat <= "0001110"; --F
end case;
end process;
end aAfisareDistanta;
是的。我想我必须将多路复用器修改为8比1或什么？ 我知道nexys 4的阴极很常见，但是我不太清楚显示器的工作原理。