lcd.vhd

来自「使用C语言与VHDL实现 液晶显示控制器示例使用说明 使用模块有：单片机模块」· VHDL 代码 · 共 39 行

   library ieee;
   use ieee.std_logic_1164.all;
  
   entity lcd is
   port(DP1,DP2,DP3 : in std_logic; --78E58的A8，A9，A10
        RS,CS1,CS2  : out std_logic;
        LCDE   : out std_logic;
        RW    : out std_logic);
   end lcd ;--
  ---
   architecture hav of lcd is
    begin 
     process(DP1,DP2,DP3)
       begin  
      
         if( DP1='0' and DP2='0' and DP3='0') then        --选种1区，读状态       
          lcde<='1';rs<='0';rw<='1';cs1<='1';cs2<='0';
         elsif(DP1='0' and DP2='0' and DP3='1')then       --选种1区，写指令     
         lcde<='1';rs<='0';rw<='0';cs1<='1';cs2<='0';    
         elsif(DP1='0' and DP2='1' and DP3='0')then       --禁止使用
          lcde<='0';rs<='1';rw<='1';cs1<='1';cs2<='0';
         elsif(DP1='0' and DP2='1' and DP3='1')then       --选种1区，写数据     
          lcde<='1';rs<='1';rw<='0';cs1<='1';cs2<='0';
        elsif(DP1='1' and DP2='0' and DP3='0')then        --选种2区，读状态     
          lcde<='1';rs<='0';rw<='1';cs1<='0';cs2<='1';
        elsif(DP1='1' and DP2='0' and DP3='1')then        --选种2区，写指令  
          lcde<='1';rs<='0';rw<='0';cs1<='0';cs2<='1';
        elsif(DP1='1' and DP2='1' and DP3='0')then        --禁止使用
          lcde<='0';rs<='1';rw<='1';cs1<='0';cs2<='1';
        elsif(DP1='1' and DP2='1' and DP3='1')then        --选种2区，写数据    
          lcde<='1';rs<='1';rw<='0';cs1<='0';cs2<='1';
        else
            lcde<='0';rs<='1';rw<='1';cs1<='0';cs2<='0';  --禁止使用
         end if;
          end process;
       end hav;