is there some 7 segment code example

Please explain better what you need.

If you simply want to connect a 7 segment display to a binary counter, here is some VHDL code.

entity decoder7seg is
    port (DIGIT : in std_logic_vector(3 downto 0);  
            SEG : out std_logic_vector(6 downto 0) );
end entity decoder7seg; 
architecture decoder7seg_a of decoder7seg is
    begin  
      --decode : process DIGIT is
      SEG <= "0111111" when DIGIT="00000" else   -- 0
             "0000110" when DIGIT="0001" else   -- 1
             "1011011" when DIGIT="0010" else   -- 2
             "1001111" when DIGIT="0011" else   -- 3
             "1100110" when DIGIT="0100" else   -- 4
             "1101101" when DIGIT="0101" else   -- 5
             "1111101" when DIGIT="0110" else   -- 6
             "0000111" when DIGIT="0111" else   -- 7
             "1111111" when DIGIT="1000" else   -- 8
             "1101111" when DIGIT="1001" else   -- 9
             "1110111" when DIGIT="1010" else   -- A
             "1111100" when DIGIT="1011" else   -- b
             "0111001" when DIGIT="1100" else   -- C
             "1011110" when DIGIT="1101" else   -- d
             "1111001" when DIGIT="1110" else   -- E
             "1110001" when DIGIT="1111" else   -- F
             "0000000";
    end architecture decoder7seg_a;

I don't describe connection between SEG bits and each display segments, since it should be easy to understand.

Cris