vgasingl.vhd

流水灯

library IEEE;
use IEEE.STD_LOGIC_1164.all;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity VGAsingl is
 PORT( CLK,MD:IN STD_LOGIC;HS,VS:OUT STD_LOGIC;
RGB_OUT:OUT STD_LOGIC_VECTOR(7 downto 0));
END VGAsingl;
ARCHITECTURE behav OF VGAsingl IS
  SIGNAL HS1,VS1,FCLK,CCLK:STD_LOGIC;
  SIGNAL MMD:STD_LOGIC_VECTOR(1 DOWNTO 0);
  SIGNAL FS :STD_LOGIC_VECTOR(5 DOWNTO 0);
  SIGNAL CC :STD_LOGIC_VECTOR(4 DOWNTO 0);
  SIGNAL LL :STD_LOGIC_VECTOR(8 DOWNTO 0);
  SIGNAL GRBX:STD_LOGIC_VECTOR(3 DOWNTO 1);
  SIGNAL GRBY:STD_LOGIC_VECTOR(3 DOWNTO 1);
  SIGNAL GRBP:STD_LOGIC_VECTOR(3 DOWNTO 1);
  SIGNAL GRB :STD_LOGIC_VECTOR(3 DOWNTO 1);
BEGIN
  GRB(2)<=(GRBP(2) XOR MD) AND HS1 AND VS1;
  GRB(3)<=(GRBP(3) XOR MD) AND HS1 AND VS1;
  GRB(1)<=(GRBP(1) XOR MD) AND HS1 AND VS1;
PROCESS(MD)
BEGIN
    IF MD'EVENT AND MD ='0' THEN 
       IF MMD="10" THEN MMD<="00";
         ELSE MMD<=MMD+1;END IF;
    END IF; 
END PROCESS;  
  PROCESS(MMD)
    BEGIN
      IF MMD="00" THEN GRBP<=GRBX;
       ELSIF MMD="01" THEN GRBP<=GRBY;
       ELSIF MMD="10" THEN GRBP<=GRBX XOR GRBY;
         ELSE GRBP<="000";END IF;
END PROCESS;
   PROCESS(CLK)		--div 50
     BEGIN
       IF CLK'EVENT AND CLK='1' THEN
           IF FS=40 THEN FS<="000000";
              ELSE FS<=FS+1; END IF;
       END IF;
END PROCESS;
FCLK<=FS(5);
PROCESS(FCLK)		--div29
   BEGIN
     IF FCLK'EVENT AND FCLK='1' THEN
        IF CC=29 THEN CC<="00000";
           ELSE CC<=CC+1;END IF;
     END IF;
END PROCESS;
CCLK<=CC(4);
PROCESS(CCLK)		--481
 BEGIN
     IF CCLK'EVENT AND CCLK='0' THEN
       IF LL=240 THEN LL<="000000000";
         ELSE LL<=LL+1; END IF;
     END IF;
END PROCESS;
PROCESS(CC,LL)
BEGIN
  IF CC>23 THEN HS1<='0';
      ELSE HS1<='1';END IF;
  IF LL>237 THEN VS1<='0';
      ELSE VS1<='1';END IF;
END PROCESS;
PROCESS(CC,LL)
 BEGIN
	--if fs=30 then
   IF CC<3  THEN GRBX<="111";
    ELSIF CC<6  THEN GRBX<="110";
    ELSIF CC<9  THEN GRBX<="101";
    ELSIF CC<12 THEN GRBX<="100";
    ELSIF CC<15  THEN GRBX<="011";
    ELSIF CC<18  THEN GRBX<="010";
    ELSIF CC<21  THEN GRBX<="001";
     ELSE GRBX<="000" ; END IF;
        IF LL<30  THEN GRBY<="111";
     ELSIF LL<60 THEN GRBY<="110";
     ELSIF LL<90 THEN GRBY<="101";
     ELSIF LL<120 THEN GRBY<="100";
     ELSIF LL<150 THEN GRBY<="011";
     ELSIF LL<180 THEN GRBY<="010";
     ELSIF LL<210 THEN GRBY<="001";
     ELSE GRBY<="000"; END IF;
	--else
	--GRBX<="000";
	--GRBY<="000";
	--end if;
	
	
   END PROCESS;
   HS<=HS1;VS<=VS1;
	RGB_OUT(7 downto 5)<="111"when GRB(2) ='1' else "000";
	RGB_OUT(4 downto 2)<="111"when GRB(3) ='1' else "000";
	RGB_OUT(1 downto 0)<="11"when GRB(1) ='1' else "00";
END behav;