用VHDL结构描述设计一个4位七段数码管动态显示电路,在时钟信号的作用下,以递增的方式在4位数码管上从0000到9999循环计数显示
时间: 2024-05-01 21:23:57 浏览: 34
首先,我们需要一个时钟信号,它将控制我们的电路以递增的方式计数。我们可以使用一个计数器来实现这一点,然后将其输出连接到七段数码管的输入以进行动态显示。
以下是一个简单的VHDL代码,它描述了一个4位七段数码管动态显示电路:
```vhdl
library ieee;
use ieee.std_logic_1164.all;
entity seven_segment is
port(
clk: in std_logic; -- 时钟信号
seg: out std_logic_vector(6 downto 0); -- 七段数码管的输出
an: out std_logic_vector(3 downto 0) -- 4位数码管的选择信号
);
end entity;
architecture behavioral of seven_segment is
signal count: integer range 0 to 9999 := 0; -- 计数器
begin
process(clk)
begin
if rising_edge(clk) then -- 在时钟上升沿触发
count <= count + 1; -- 计数器加1
if count > 9999 then -- 如果计数器超过9999,重置为0
count <= 0;
end if;
end if;
end process;
process(count)
variable digit: integer range 0 to 3 := 0; -- 数码管选择信号
variable value: integer range 0 to 9999 := 0; -- 数码管显示数值
begin
value := count;
for i in 0 to 3 loop
digit := i;
case digit is
when 0 =>
seg <= "0000001" when value mod 10 = 0 else
"1001111" when value mod 10 = 1 else
"0010010" when value mod 10 = 2 else
"0000110" when value mod 10 = 3 else
"1001100" when value mod 10 = 4 else
"0100100" when value mod 10 = 5 else
"0100000" when value mod 10 = 6 else
"0001111" when value mod 10 = 7 else
"0000000" when value mod 10 = 8 else
"0000100" when value mod 10 = 9;
when 1 =>
seg <= "0000001" when value / 10 mod 10 = 0 else
"1001111" when value / 10 mod 10 = 1 else
"0010010" when value / 10 mod 10 = 2 else
"0000110" when value / 10 mod 10 = 3 else
"1001100" when value / 10 mod 10 = 4 else
"0100100" when value / 10 mod 10 = 5 else
"0100000" when value / 10 mod 10 = 6 else
"0001111" when value / 10 mod 10 = 7 else
"0000000" when value / 10 mod 10 = 8 else
"0000100" when value / 10 mod 10 = 9;
when 2 =>
seg <= "0000001" when value / 100 mod 10 = 0 else
"1001111" when value / 100 mod 10 = 1 else
"0010010" when value / 100 mod 10 = 2 else
"0000110" when value / 100 mod 10 = 3 else
"1001100" when value / 100 mod 10 = 4 else
"0100100" when value / 100 mod 10 = 5 else
"0100000" when value / 100 mod 10 = 6 else
"0001111" when value / 100 mod 10 = 7 else
"0000000" when value / 100 mod 10 = 8 else
"0000100" when value / 100 mod 10 = 9;
when 3 =>
seg <= "0000001" when value / 1000 mod 10 = 0 else
"1001111" when value / 1000 mod 10 = 1 else
"0010010" when value / 1000 mod 10 = 2 else
"0000110" when value / 1000 mod 10 = 3 else
"1001100" when value / 1000 mod 10 = 4 else
"0100100" when value / 1000 mod 10 = 5 else
"0100000" when value / 1000 mod 10 = 6 else
"0001111" when value / 1000 mod 10 = 7 else
"0000000" when value / 1000 mod 10 = 8 else
"0000100" when value / 1000 mod 10 = 9;
when others =>
seg <= "1111111"; -- 显示空白
end case;
an <= "1110" when i = 0 else -- 选择第一个数码管
"1101" when i = 1 else -- 选择第二个数码管
"1011" when i = 2 else -- 选择第三个数码管
"0111" when i = 3 else -- 选择第四个数码管
"1111"; -- 关闭所有数码管
wait for 2 ms; -- 等待2毫秒,使数码管显示动态
end loop;
end process;
end architecture;
```
在这里,我们使用了两个进程。第一个进程用于计数器的递增和重置,而第二个进程用于七段数码管的动态显示。我们使用一个变量digit来选择要显示的数码管,并将其输出到4位数码管的an端口。然后,我们使用一个变量value来存储要显示的数字,并将其分解为每个数码管的数字。我们使用一个case语句来将数字转换为七段数码管的输出,并将其输出到seg端口。最后,我们使用wait for语句来等待2毫秒,以使数码管的显示动态。
请注意,这只是一个简单的实现,可能需要根据您的具体要求进行修改。