Using 7 segment on De1 Board

To count how many '1's ( or '0's ) you may design a majority circuit. This code:

jurado1: process (t1)

variable m1 : unsigned (2 downto 0);

begin

m1:=TO_UNSIGNED(0,3);

for i in 0 to 3 loop

if (t1(i) = '1') then

m1:=m1+1;

end if;

end loop;

count <= m1;

end process jurado1;

count will have the numbers of '1's on vector t1 ( 4 bits ). I don't know how many '1's do want count. For a greater number of switch a sequential counter will be easier.

Of course you have to decode bcd number on count, to 7 segment code. If you count more than 9 '1's you'll need 2 digits, so you need a bin to bcd converter.