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Altera_Forum's avatar
Altera_Forum
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12 years ago

7 bit in 2 seven segments

hi guys i'm having a bit of a problem trying to figure out how to represent binary numbers up to 99 in 2 seven segments.

i have my decoder code 


library ieee;
use ieee.std_logic_1164.all;
entity Decodificador is
	port(
		bcd: in  std_logic_vector(3 downto 0);
		led: out std_logic_vector(6 downto 0)
		);
	end Decodificador;
architecture rtl of Decodificador is
	begin
process (bcd)
begin
case bcd is
		when "0000" => LED <= "1111110";
		when "0001" => LED <= "1100000";
		when "0010" => LED <= "1011011";
		when "0011" => LED <= "1110011";
		when "0100" => LED <= "1100101";
		when "0101" => LED <= "0110111";
		when "0110" => LED <= "0111111";
		when "0111" => LED <= "1100010";	
		when "1000" => LED <= "1111111";
		when "1001" => LED <= "1110111";
		when others => LED <= "0000000";
		end case;
	end process;
end rtl;

still it will get up to 9, is there any form to represent the numbers up to 99 without having to declare 99 cases?

thank you.

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    Yes, use your grey cells, you are halfway there : divide and conquer

    A tip: think of re-use of module/code
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    I think you first have to convert a binary natural number into BCD and then instance two times decodificador, one for the units digit and one for the tens.

    Remember that 33 in decimal needs 8 bit in BCD (0011 0011) so your convertion module is charge to generate BCD code for units and BCD code for tens.

    for example:

    process(...)

    .......

    if(bin>=10 and bin<20) then bcd_tens<="0001"

    ........

    for the units i think you should be able to drive the related decodificator with (bin mod 10) that should be the BCD units by itself.....
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    thank you memes for your help, as you said had to convert it to bcd, now i made it, thank you guys