我正在使用VHDL Altera板处理数字时钟。而且我在编码期间遇到了困难。我试图制作一个数字时钟，显示六个7段的小时，分钟和秒。我的代码是这样的：
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
entity time_main is
port(clk_50mhz, reset, min_sw, hour_sw: in std_logic;
fnd_s: out std_logic_vector(5 downto 0);
fnd_d: out std_logic_vector(7 downto 0));
end time_main;
architecture clock of time_main is
signal clk_cnt: integer range 0 to 50000000;
signal data1, data3, data5, temp: integer range 0 to 9;
signal data2, data4: integer range 0 to 5;
signal data6: integer range 0 to 2;
signal cnt: integer range 0 to 5;
signal clk_test: integer range 0 to 5000000000;
variable decode_seg: std_logic_vector(7 downto 0);
begin
case count_seg is
when 0 => decode_seg := "00111111";
when 1 => decode_seg := "00000110";
when 2 => decode_seg := "01011011";
when 3 => decode_seg := "01001111";
when 4 => decode_seg := "01100110";
when 5 => decode_seg := "01101101";
when 6 => decode_seg := "01111101";
when 7 => decode_seg := "00100111";
when 8 => decode_seg := "01111111";
when 9 => decode_seg := "01101111";
when others => decode_seg := "00000000";
end case;
return(decode_seg);
end dis_7_seg;
begin
process(clk_50mhz)
begin
if(clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
clk_cnt <= 0;
else
clk_cnt <= clk_cnt + 1;
end if;
end if;
end process;
sec_1: process(clk_50mhz, reset)
begin
if(reset = '0') then
data1 <= 0;
elsif(clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data1 = 9) then
data1 <= 0;
else
data1 <= data1 + 1;
end if;
end if;
end if;
end process;
sec_10: process(clk_50mhz, reset)
begin
if(reset = '0') then
data2 <= 0;
elsif(clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data1 = 9) then
if(data2 = 5) then
data2 <= 0;
else
data2 <= data2 + 1;
end if;
end if;
end if;
end if;
end process;
min_1: process(clk_50mhz, reset)
begin
if(reset = '0') then
data3 <= 0;
elsif(min_sw = '1') and (clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data3 = 9) then
data3 <= 0;
else
data3 <= data3 + 1;
end if;
end if;
elsif(clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data1 = 9 and data2 = 5) then
if(data3 = 9) then
data3 <= 0;
else
data3 <= data3 + 1;
end if;
end if;
end if;
end if;
end process;
min_10: process(clk_50mhz, reset)
begin
if(reset = '0') then
data4 <= 0;
elsif(min_sw = '1') and (clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data3 = 9) then
if(data4 = 5) then
data4 <= 0;
else
data4 <= data4 + 1;
end if;
end if;
end if;
if(clk_cnt = 50000000) then
elsif(clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data1 = 9 and data2 = 5 and data3 = 9) then
if(data4 = 5) then
data4 <= 0;
else
data4 <= data4 + 1;
end if;
end if;
end if;
end if;
end if;
end process;
hour_1: process(clk_50mhz, reset)
begin
if(reset = '0') then
data5 <= 0;
elsif(hour_sw = '1') and (clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data5 = 3 and data6 = 2) then
data5 <= 0;
elsif(data5 = 9) then
data5 <= 0;
else
data5 <= data5 + 1;
end if;
end if;
elsif(clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data1 = 9 and data2 = 5 and data3 = 9 and data4 = 5) then
if(data5 = 3 and data6 = 2) then
data5 <= 0;
elsif(data5 = 9)then
data5 <= 0;
else
data5 <= data5 + 1;
end if;
end if;
end if;
end if;
end process;
hour_10: process(clk_50mhz, reset)
begin
if(reset = '0') then
data6 <= 0;
elsif(hour_sw = '1') and (clk_50mhz'event and clk_50mhz = '1') then
if(clk_cnt = 50000000) then
if(data5 = 3 and data6 = 2) then
data6 <= 0;
elsif(data5 = 9) then
data6 <= data6 + 1;
end if;
end if;
elsif(clk_50mhz'event and clk_50mhz = '1') then -
if(clk_cnt = 50000000) then
if(data1 = 9 and data2 = 5 and data3 = 9 and data4 = 5) then
if(data5 = 3 and data6 = 2) then
data6 <= 0;
elsif(data5 = 9) then
data6 <= data6 + 1;
end if;
end if;
end if;
end if;
end process;
process(clk_50mhz)
begin
if(clk_50mhz'event and clk_50mhz = '1') then
if(clk_test = 5000000000) then
clk_test <= 0;
else
clk_test <= clk_test + 1;
end if;
end if;
end process;
process(clk_test)
begin
if(clk_test = 5000000000) then
if(cnt = 5) then
cnt <= 0;
else
cnt <= cnt + 1;
end if;
end if;
end process;
process(data1, data2, data3, data4, data5, data6, cnt)
begin
If (cnt=0) then
fnd_s <= "000001";
temp <= data1;
else if(cnt=1) then
fnd_s <= "000010";
temp <= data2;
else if (cnt=2) then
fnd_s <= "000100";
temp <= data3;
else if (cnt=3) then
fnd_s <= "001000";
temp <= data4;
else if (cnt=4) then
fnd_s <= "010000";
temp <= data5;
else if (cnt=5) then
fnd_s <= "100000";
temp <= data6;
end if;
end if;
end if;
end if;
end if;
end if;
end process;
fnd_d <= dis_7_seg(temp);
end clock;
=============================================== =========================
然而，我发现第一段没有显示任何东西，只是总OFF ...我发现其他5段显示相同的数字：从0到9持续9秒，然后段显示0再次，并从0到9继续计数。我以为我做了一个很好的代码，足以制作小时，分钟和秒......但它只显示了几秒钟......有人能告诉我我的代码有什么问题吗？拜托？