vhdl实现8421bcd转二进制
时间: 2023-03-28 15:04:30 浏览: 180
可以使用以下代码实现8421BCD码转二进制:
```
library ieee;
use ieee.std_logic_1164.all;
entity bcd_to_bin is
port (
bcd_in : in std_logic_vector(3 downto );
bin_out : out std_logic_vector(3 downto )
);
end entity bcd_to_bin;
architecture rtl of bcd_to_bin is
begin
process(bcd_in)
begin
case bcd_in is
when "000" => bin_out <= "000";
when "0001" => bin_out <= "0001";
when "001" => bin_out <= "001";
when "0011" => bin_out <= "0011";
when "010" => bin_out <= "010";
when "0101" => bin_out <= "0101";
when "011" => bin_out <= "011";
when "0111" => bin_out <= "0111";
when "100" => bin_out <= "100";
when "1001" => bin_out <= "1001";
when others => bin_out <= "XXXX";
end case;
end process;
end architecture rtl;
```
这是一个简单的 VHDL 实体,它将 4 位的 BCD 码转换为 4 位的二进制码。在这个实体中,使用了一个 case 语句来实现转换。当输入的 BCD 码为 000 到 1001 时,输出对应的二进制码;否则,输出 "XXXX" 表示无效输入。