library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;

entity lcd is
	port (	clk_in  : in std_logic;
			lcd_on 	: out std_logic;
			e   	: out std_logic;      -- LCD Enable Bit --
			rs   	: out std_logic;      -- Control Bit --
			rw    	: out std_logic;      -- Control Bit --
			data   	: out std_logic_vector(7 downto 0));  -- LCD Data --
end lcd;

architecture ldg of lcd is
	constant addr_line  : std_logic_vector(7 downto 0):= "10000000"; -- Start Display Location : 80H --
	constant function_set   : std_logic_vector(7 downto 0):= "00111100"; -- LCD Initialization : DL=1 8bit,N =1 2 lines,F=0 5*8 dot font --
	constant clear_display  : std_logic_vector(7 downto 0):= "00000001"; -- Clear LCD Screen --
	constant entry_mode_set : std_logic_vector(7 downto 0):= "00000110"; -- Mode Setting , I/D=1 increment, S =0 cursor shift on data entry--
	constant display_on_off : std_logic_vector(7 downto 0):= "00001110"; -- Display ON/Off , D =1 display on, C =1 cursor on, B=0 blink no--
	signal clk : std_logic;
begin
	process(clk_in)
		variable count2 : integer range 0 to 60000 := 0;
	begin
		if(clk_in='1' and clk_in'event) then
			count2 := count2 + 1;
			if (count2 = 60000) then
				clk <= not clk;
				count2 := 0;
			end if;
		end if;
	end process;
	process(clk)
		variable count : std_logic_vector(4 downto 0) := "00000";
	begin
		if(clk' event and clk = '1') then
			case count is
				when "00000" =>
					rs <= '0';
					rw <= '0';
					data <= function_set;   --LCD Initialization
					count := count + 1;
				when "00001" =>
					rs <= '0';
					rw <= '0';
					data <= clear_display;  -- Clear LCD Screen 
					count := count + 1;
				when "00010" =>
					rs <= '0';
					rw <= '0';
					data <= entry_mode_set; -- Mode Setting
					count := count + 1;
				when "00011" =>
					rs <= '0';
					rw <= '0';
					data <= display_on_off; -- display on/off
					count := count + 1;
				when "00100" =>
					rs <= '0';
					rw <= '0';
					data <= addr_line;      -- Start Display Location : 80H
					count := count + 1;
   
				when "00101" =>
					rs <= '1';
					rw <= '0';
					data <= "01001101";    --M
					count := count + 1;
				when "00110" =>
					rs <= '1';
					rw <= '0';
					data <= "01010010";    --R
					count := count + 1;
				when "00111" =>
					rs <= '1';
					rw <= '0';
					data <= "00100000";    --" "
					count := count + 1;
				when "01000" =>
					rs <= '1';
					rw <= '0';
					data <= "01001101";    --M
					count := count + 1;
				when "01001" =>
					rs <= '1';
					rw <= '0';
					data <= "01001111";    --O
					count := count + 1; 
				when "01010" =>
					rs <= '1';
					rw <= '0';
					data <= "01001110";    --N
					count := count + 1;
				when "01011" =>
					rs <= '1';
					rw <= '0';
					data <= "01001011";    --K
					count := count + 1;
				when "01100" =>
					rs <= '1';
					rw <= '0';
					data <= "01000101";    --E
					count := count + 1;
				when "01101" =>
					rs <= '1';
					rw <= '0';
					data <= "01011001";    --Y
					count := count + 1;
 
				when others =>
					rs <= '0';
					rw <= '0';
					
			end case;
		end if;
	end process;
	e <= clk;
	lcd_on <= '1';
end ldg;