lcd_display.vhd

一个毕业设计

--Copyright (C) 1991-2004 Altera Corporation
--Any megafunction design, and related net list (encrypted or decrypted),
--support information, device programming or simulation file, and any other
--associated documentation or information provided by Altera or a partner
--under Altera's Megafunction Partnership Program may be used only to
--program PLD devices (but not masked PLD devices) from Altera.  Any other
--use of such megafunction design, net list, support information, device
--programming or simulation file, or any other related documentation or
--information is prohibited for any other purpose, including, but not
--limited to modification, reverse engineering, de-compiling, or use with
--any other silicon devices, unless such use is explicitly licensed under
--a separate agreement with Altera or a megafunction partner.  Title to
--the intellectual property, including patents, copyrights, trademarks,
--trade secrets, or maskworks, embodied in any such megafunction design,
--net list, support information, device programming or simulation file, or
--any other related documentation or information provided by Altera or a
--megafunction partner, remains with Altera, the megafunction partner, or
--their respective licensors.  No other licenses, including any licenses
--needed under any third party's intellectual property, are provided herein.
--Copying or modifying any file, or portion thereof, to which this notice
--is attached violates this copyright.

library altera_vhdl_support;
use altera_vhdl_support.altera_vhdl_support_lib.all;

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

entity lcd_display is 
        port (
              -- inputs:
                 signal address : IN STD_LOGIC_VECTOR (1 DOWNTO 0);
                 signal begintransfer : IN STD_LOGIC;
                 signal read : IN STD_LOGIC;
                 signal write : IN STD_LOGIC;
                 signal writedata : IN STD_LOGIC_VECTOR (7 DOWNTO 0);

              -- outputs:
                 signal LCD_E : OUT STD_LOGIC;
                 signal LCD_RS : OUT STD_LOGIC;
                 signal LCD_RW : OUT STD_LOGIC;
                 signal LCD_data : INOUT STD_LOGIC_VECTOR (7 DOWNTO 0);
                 signal irq : OUT STD_LOGIC;
                 signal readdata : OUT STD_LOGIC_VECTOR (7 DOWNTO 0)
              );
end entity lcd_display;


architecture europa of lcd_display is

begin

  LCD_RW <= address(0);
  LCD_RS <= address(1);
  LCD_E <= read OR write;
  LCD_data <= A_WE_StdLogicVector((std_logic'((address(0))) = '1'), std_logic_vector'("ZZZZZZZZ"), writedata);
  readdata <= LCD_data;

end europa;