Clock Issue For A Vga Controller

Thanks Ben for answering.

The CYCLONE || Starter Kit has on board 3 crystals, 24MHz, 27MHz, and 50MHz. Using VHDL code, I know how to use the 7_SEGMENTS, KEYS, LEDS, etc..., but I'm having problems to use one of the crystal oscillators listed above using the same technics used to access the other peripheral onboards.

For example, if I want to write the key values to the LEDs, using the code below will do :

entity key_To_Led is

port(

key : in std_logic_vector(9 downto 0); -- key and ledr are the symbolic

-- names for the

ledr : out std_logic_vector(9 downto 0); -- 9 keys and 9 red leds on my

-- kit.

end key_To_Led;

architecture behavior of key_To_Led is

begin

ledr <= key_To_Led;

end behavior;

Now, if if for example I want to access the 50 Mhz onboard clock generator, I would have probably to use the same type of coding as :

entity vga_ctrl is

port(

CLOCK_50 : out std_logic; -- Symbolic name for 50Mhz onboard 50 Mhz

-- clock

clock_in : inout std_logic; -- VGA controller clock input;

);

end vga_ctrl;

architecture behavior of vga_ctrl is

begin

clock_in <= CLOCK_50; -- Logically, this should work; but still, it

-- does'nt.

end behavior;

Again, unless there's something wrong with my code in general, I do not know what else to

do to access any of the onboard clock generators. I'll appreciate any idea that would help.

Regards,