lcd.vhd

是一些很好的FPGA设计实例

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-- Company: 
-- Engineer: 
-- 
-- Create Date:    15:46:19 04/17/2006 
-- Design Name: 
-- Module Name:    LCD - Behavioral 
-- Project Name: 
-- Target Devices: 
-- Tool versions: 
-- Description: 
--
-- Dependencies: 
--
-- Revision: 
-- Revision 0.01 - File Created
-- Additional Comments: 
--
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library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

---- Uncomment the following library declaration if instantiating
---- any Xilinx primitives in this code.
--library UNISIM;
--use UNISIM.VComponents.all;

entity LCD is
	generic(divide_to_100k:integer:=500);
	
    Port ( clk,rst : in  STD_LOGIC;
			  s0_a,s1_a,s2_a,s3_a,s4_a,s5_a,s6_a: out std_logic;
				c1,c2: out  STD_LOGIC;
           wr : out  STD_LOGIC;
           rd : out  STD_LOGIC;
           cd : out  STD_LOGIC;
           lcd_rst : out  STD_LOGIC;
           lcd_data : out  STD_LOGIC_VECTOR (7 downto 0));
end LCD;

architecture Behavioral of LCD is

signal clk_100k:std_logic;
type state is (s0,s1,s2,s3,s4,s5,s6,s7,s8,s9,s10,s11,s12,s13,s14,s15); 
signal current_s:state;
--type state_s is (s0_0,s1_1,s2_2);
--signal current_s_s:state_s;

type instruction_code is array(0 to 12)of std_logic_vector(7 downto 0);
constant c_code:instruction_code:=(x"00",x"00",x"40",x"1e",x"00",x"41",x"80",x"94",x"07",x"00",x"24",x"b0",x"b2");
											--c_t_starting_add 		--c_t_width 	 --c_t_on		   --c_add_p c_auto_w_off
																					  --c_or_mode							  c_auto_w_on
type data_buffer is array(0 to 14)of std_logic_vector(7 downto 0);
constant data_buf:data_buffer:=(x"57",x"57",x"57",x"0E", x"13",x"11",x"15",x"59",
										  x"44",x"44",x"5A",x"0E", x"43",x"4F",x"4D");
													
begin

c1<='1';
c2<='1';

process(clk)
variable cnt:integer range 0 to divide_to_100k;
	begin
	if rising_edge(clk) then
		cnt:=cnt+1;
		if cnt=divide_to_100k then
			cnt:=0;
		end if;
		if cnt<divide_to_100k/2 then
			clk_100k<='0';
		else 
			clk_100k<='1';
		end if;
	end if;
end process;


process(clk_100k)-------------clk_100k
variable cnt1:integer range 0 to 500000;		--cnt1 for loop
variable cnt1_1:integer range 0 to 1000; 	--cnt1_1 for writing operation
variable code_cnt:integer range 0 to 13;		--cnt1_2 array of code
variable data_cnt:integer range 0 to 480;

	begin
	if rising_edge(clk_100k) then
		if rst='1' then
			current_s<=s0;
			cnt1:=0;
			cnt1_1:=0;
			code_cnt:=0;
			data_cnt:=0;
			lcd_rst<='0';
				s0_a<='0';
				s1_a<='0';
				s2_a<='0';
				s3_a<='0';
				s4_a<='0';
				s5_a<='0';
				s6_a<='0';

		else		
			case current_s is
			when s0=>
				wr<='1';
				rd<='1';
				
				cnt1:=cnt1+1;
				if cnt1<250000 then
					lcd_rst<='0';
				elsif cnt1<500000 then--500
					lcd_rst<='1';
				elsif cnt1=500000 then--500			--delay for lcd_initial
					lcd_rst<='1';
					cnt1:=0;
					current_s<=s1;
				end if;	
				s0_a<='0';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='1';
				s6_a<='1';
				
			when s1=>
				if cnt1<2 then				--control amount of c_code
					if cnt1_1<1*3 then					
						cd<='0';
					elsif cnt1_1<2*3 then
						lcd_data<=c_code(code_cnt);
						if cnt1_1=(2*3-1) then
							code_cnt:=code_cnt+1;
						end if;
					elsif cnt1_1<3*3 then
						wr<='0';
					elsif cnt1_1<4*3 then
						wr<='1';
				   -----------------------------writing a parameter
					
					elsif cnt1_1<5*3 then
						cd<='0';
					elsif cnt1_1<6*3 then
						lcd_data<=c_code(code_cnt);
						if cnt1_1=6*3-1 then
							code_cnt:=code_cnt+1;
						end if;
					elsif cnt1_1<7*3 then
						wr<='0';
					elsif cnt1_1<8*3 then
						wr<='1';
					-----------------------------writing a parameter	
					
					elsif cnt1_1<9*3 then
						cd<='1';
					elsif cnt1_1<10*3 then
						lcd_data<=c_code(code_cnt);
						if cnt1_1=10*3-1 then
							code_cnt:=code_cnt+1;
						end if;
					elsif cnt1_1<11*3 then
						wr<='0';
					elsif cnt1_1<12*3 then
						wr<='1';
					end if;	
				end if;					
					-----------------------------writing a code	
					
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					cnt1:=cnt1+1;
					if cnt1=2 then
						current_s<=s2;
						cnt1:=0;
					end if;
				end if;
				
				s0_a<='1';
				s1_a<='0';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='1';
				s6_a<='1';
				
			when s2=>
				if cnt1<2 then				--control amount of c_code
					if cnt1_1<1*3 then
						cd<='1';
					elsif cnt1_1<2*3 then
						lcd_data<=c_code(code_cnt);
						if cnt1_1=2*3-1 then
							code_cnt:=code_cnt+1;
						end if;
					elsif cnt1_1<3*3 then
						wr<='0';
					elsif cnt1_1<4*3 then
						wr<='1';
					end if;	
				end if;								
					-----------------------------writing a code		
					
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					cnt1:=cnt1+1;
					if cnt1=2 then
						current_s<=s3;
						cnt1:=0;
					end if;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='0';
				s3_a<='1';
				s4_a<='1';
				s5_a<='1';
				s6_a<='1';
				
			when s3=>-------------------------set add_p and auto_write		
				if cnt1_1<1*3 then					
					cd<='0';
				elsif cnt1_1<2*3 then
					lcd_data<=c_code(8);
				elsif cnt1_1<3*3 then
					wr<='0';
				elsif cnt1_1<4*3 then
					wr<='1';
			   -----------------------------writing a parameter
				
				elsif cnt1_1<5*3 then
					cd<='0';
				elsif cnt1_1<6*3 then
					lcd_data<=c_code(9);
				elsif cnt1_1<7*3 then
					wr<='0';
				elsif cnt1_1<8*3 then
					wr<='1';
				-----------------------------writing a parameter	
				
				elsif cnt1_1<9*3 then
					cd<='1';
				elsif cnt1_1<10*3 then
					lcd_data<=c_code(10);
				elsif cnt1_1<11*3 then
					wr<='0';
				elsif cnt1_1<12*3 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					current_s<=s4;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='0';
				s4_a<='1';
				s5_a<='1';
				s6_a<='1';
				
			when s4=>
				if cnt1_1<1*3 then
					cd<='1';
				elsif cnt1_1<2*3 then
					lcd_data<=c_code(11);
				elsif cnt1_1<5*3 then
					wr<='0';
				elsif cnt1_1<6*3 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					current_s<=s5;
					data_cnt:=0;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='0';
				s5_a<='1';
				s6_a<='1';
			when s5=>
				if cnt1_1<1*3 then					
					cd<='0';
				elsif cnt1_1<2*3 then
					lcd_data<=x"37";
					data_cnt:=data_cnt+1;
				elsif cnt1_1<3*3 then
					wr<='0';
				elsif cnt1_1<4*3 then
					wr<='1';
				end if;
			   -----------------------------writing a data	
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					if data_cnt=480 then
						current_s<=s6;
						data_cnt:=0;
					end if;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='0';
				s6_a<='1';	
			when s6=>
				if cnt1_1<1*3 then
					cd<='1';
				elsif cnt1_1<2*3 then
					lcd_data<=c_code(12);
				elsif cnt1_1<3*3 then
					wr<='0';
				elsif cnt1_1<4*3 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;----------------------------------------------------------
					current_s<=s7;--------------------------------------------------------
				end if;	
				
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='1';
				s6_a<='0';				
			when s7=>-------------------------set add_p and auto_write		
				if cnt1_1=0 then					
					cd<='0';
				elsif cnt1_1=1 then
					lcd_data<=x"00";
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
			   -----------------------------writing a parameter
				
				elsif cnt1_1=4 then
					cd<='0';
				elsif cnt1_1=5 then
					lcd_data<=x"00";
				elsif cnt1_1=6 then
					wr<='0';
				elsif cnt1_1=7 then
					wr<='1';
				-----------------------------writing a parameter	
				
				elsif cnt1_1=8 then
					cd<='1';
				elsif cnt1_1=9 then
					lcd_data<=c_code(10);
				elsif cnt1_1=10 then
					wr<='0';
				elsif cnt1_1=11 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					current_s<=s8;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='0';
				s4_a<='1';
				s5_a<='1';
				s6_a<='1';
				
			when s8=>
				if cnt1_1=0 then
					cd<='1';
				elsif cnt1_1=1 then
					lcd_data<=c_code(11);
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					current_s<=s9;
					data_cnt:=0;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='0';
				s5_a<='1';
				s6_a<='1';				
			when s9=>
				if cnt1_1=0 then					
					cd<='0';
				elsif cnt1_1=1 then
					lcd_data<=x"00";
					data_cnt:=data_cnt+1;
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
				end if;
			   -----------------------------writing a data	
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					if data_cnt=480 then
						current_s<=s10;
						data_cnt:=0;
					end if;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='0';
				s6_a<='1';
				
			when s10=>
				if cnt1_1=0 then
					cd<='1';
				elsif cnt1_1=1 then
					lcd_data<=c_code(12);
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;----------------------------------------------------------
					current_s<=s11;--------------------------------------------------------
				end if;	
				
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='1';
				s6_a<='0';
				
				

			when s11=>-------------------------set add_p and auto_write		
				if cnt1_1=0 then					
					cd<='0';
				elsif cnt1_1=1 then
					lcd_data<=c_code(8);
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
			   -----------------------------writing a parameter
				
				elsif cnt1_1=4 then
					cd<='0';
				elsif cnt1_1=5 then
					lcd_data<=c_code(9);
				elsif cnt1_1=6 then
					wr<='0';
				elsif cnt1_1=7 then
					wr<='1';
				-----------------------------writing a parameter	
				
				elsif cnt1_1=8 then
					cd<='1';
				elsif cnt1_1=9 then
					lcd_data<=c_code(10);
				elsif cnt1_1=10 then
					wr<='0';
				elsif cnt1_1=11 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					current_s<=s12;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='0';
				s4_a<='1';
				s5_a<='1';
				s6_a<='1';
				
			when s12=>
				if cnt1_1=0 then
					cd<='1';
				elsif cnt1_1=1 then
					lcd_data<=c_code(11);
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					current_s<=s13;
					data_cnt:=0;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='0';
				s5_a<='1';
				s6_a<='1';				
			when s13=>
				if cnt1_1=0 then					
					cd<='0';
				elsif cnt1_1=1 then
					lcd_data<=data_buf(data_cnt);
					data_cnt:=data_cnt+1;
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
				end if;
			   -----------------------------writing a data	
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;
					if data_cnt=15 then
						current_s<=s14;
						data_cnt:=0;
					end if;
				end if;
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='0';
				s6_a<='1';
				
			when s14=>
				if cnt1_1=0 then
					cd<='1';
				elsif cnt1_1=1 then
					lcd_data<=c_code(12);
				elsif cnt1_1=2 then
					wr<='0';
				elsif cnt1_1=3 then
					wr<='1';
				end if;	
				-----------------------------writing a code		
				
				cnt1_1:=cnt1_1+1;
				if cnt1_1=100 then	
					cnt1_1:=0;----------------------------------------------------------
					current_s<=s15;--------------------------------------------------------
				end if;	
				
				s0_a<='1';
				s1_a<='1';
				s2_a<='1';
				s3_a<='1';
				s4_a<='1';
				s5_a<='1';
				s6_a<='0';

			when s15=>
				null;
			when others=>
				current_s<=s0;
			end case;
		end if;
	end if;
end process;
					
				

end Behavioral;