VHDL12864显示采样电压.doc

/12864显示 “采样电压”及 keyin 输入数字量的后转化为 数字 ：如（“11111”为 5.0V ）/本例程只是提供一个思路library ieee;use ieee.std_logic_1164.all;use ieee.std_logic_arith.all;use ieee.std_logic_unsigned.all;entity lcd12864 is port( clk,reset: in std_logic; en,rw,rs: OUT std_logic; data: out std_logic_vector(7 downto 0); keyin:in std_logic_vector(4 downto 0);end entity lcd12864 ;architecture behav of lcd12864 is type states is(st0,st1,st2,st3,st4,st5,st6); type ram1 is array(0 to 9) of std_logic_vector(7 downto 0); type ram2 is array(0 to 7) of std_logic_vector(7 downto 0); constant cgram1 : ram1 :=(x30,x31,x32,x33,x34,x35,x36,x37,x38,x39); -0123456789的ASCII码 constant cyda : ram2:=(xb2,xc9,xd1,xf9,xb5,xe7,xd1,xb9);/“采样电压”可查看12864字符手册 signal current_state: states; signal lcd_clk,clk_out:std_logic; signal shi_clk,yifen_clk,shifen_clk,yimiao_clk,shimiao_clk:std_logic; signal ad:integer; beginprocess(CLK) variable n1:integer range 0 to 100000; -将输入时钟分频为250hz,4ms begin if rising_edge(Clk) then if n1100000 then n1:=n1+1; else n1:=0; Clk_Out=not Clk_Out; end if; end if;end process;en=clk_out;lcd_clk=clk_out; RW = 0 ;process(clk)begin if clkevent and clk=1 thenad=conv_integer(keyin);end if;end process;process(LCD_Clk,Reset,Current_State) variable cn2: integer range 0 to 10 ;variable miaoge,miaoshi,fenge,fenshi,shi1,shi2:integer range 0 to 9; begin if Reset=0 then Current_State=st0; RS=0; elsif rising_edge(LCD_Clk) then Current_State = Current_State ; RS -基本指令集动作 Data=00110000; Current_State - 整体显示设置：光标off 反光off：0x0c Data=00001100; Current_State -清除显示，并且认定地址指针为00h:0x01 Data=00000001; Current_State -指定游标的移动方向及指定显示的移位：06 Data=00000110; Current_State -地址设定 从第一行的第一个字开始显示到第五个字 地址设定if cn26 then cn2:=cn2+1; else cn2:=0; end if; if cn2=0 then data=10001000;-0x80 elsif cn2=1 then data=10001001;-0x81 elsif cn2=2 then data=10000000;-0x82 elsif cn2=3 then data=10000001;-0x83 elsif cn2=4 then data=10000010;-0x83 elsif cn2=5 then data=10000011;-0x83 elsif cn2=6 then data=10001010;-0x83 end if; Current_State -送数据1 一个字地址可以放两个数字，所以一个地址送两次数据 rs=1; if cn2=0 then data=cgram1(conv_integer(shi2); elsif cn2=1 then data=cgram1(conv_integer(shi1);elsif cn2=2 then data=cyda(0);elsif cn2=3 then data=cyda(2);elsif cn2=4 then data=cyda(4);elsif cn2=5 then data=cyda(6);elsif cn2=6 then data=01010110;end if; current_state -送数据2rs=1;if cn2=0 then data=00101110; elsif cn2=1 then data=00100000; elsif cn2=2 then data=cyda(1); elsif cn2=3 then data=cyda(3);elsif cn2=4 then data=cyda(5);elsif c