步长可变的加减计数器

use ieee.std_logic_11.all; use ieee.std_logic_unsigned.all;

entity buchang is

generic(N: integer:=4); port(

clk,f1,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16:in std_logic; --k :std_logic;

--cq :out std_logic_vector(7 downto 0); q :out std_logic_vector(7 downto 0);

ledag,ledag1 :out std_logic_vector(6 downto 0) );

end buchang;

Architecture a of buchang is

signal cnt: integer range 0 to n-1; signal k: integer range 0 to 15; signal clkout: std_logic;

signal cq: std_logic_vector(7 downto 0); --q1<=q(3 downto 0); --q2<=q(7 downto 4);

signal q1,q2: std_logic_vector(3 downto 0);

Begin

process(clk) begin

if(clk'event and clk='1') then if(cntcnt <= 0; end if; end if; end process;

--------------------------------

process(cnt) begin

if(cntclkout <= '1'; else

clkout <= '0'; end if; end process;

--------------------------------------------------------

process(clkout) begin

if(clkout'event and clkout='1') then if f1='1' then cq<=cq+1+k;

if cq=\"11111111\"then cq<=\"00000000\"; end if; end if; end if;

if(clkout'event and clkout='1') then if f1='0' then cq<=cq-1-k;

if cq=\"00000000\"then cq<=\"11111111\"; end if; end if; end if ;

-- else

--cq<=cq-1-k;

--if cq=\"00000000\"then cq<=\"11111111\"; -- end if; --end if; end process;

q<= cq;

q1<=cq(7 downto 4); q2<=cq(3 downto 0);

process(k) begin

if a1='1'then k<= 0; elsif a2='1' then k<= 1; elsif a3='1' then k<= 2; elsif a4='1' then k<= 3; elsif a5='1' then k<= 4; elsif a6='1' then k<= 5;

elsif a7='1' then k<= 6; elsif a8='1' then k<= 7; elsif a9='1' then k<= 8; elsif a10='1' then k<= 9; elsif a11='1' then k<= 10; elsif a12='1' then k<= 11; elsif a13='1' then k<= 12; elsif a14='1' then k<= 13; elsif a15='1' then k<= 14; elsif a16='1' then k<= 15; end if;

end process;

process(q1) begin

case q1 is

when \"0000\" => ledag <=\"0111111\"; when \"0001\" => ledag <=\"0000110\"; when \"0010\" => ledag <=\"1011011\"; when \"0011\" => ledag <=\"1001111\"; when \"0100\" => ledag <=\"1100110\"; when \"0101\" => ledag <=\"1101101\"; when \"0110\" => ledag <=\"1111101\"; when \"0111\" => ledag <=\"0000111\"; when \"1000\" => ledag <=\"1111111\"; when \"1001\" => ledag <=\"1101111\"; when \"1010\" => ledag <=\"1110111\"; when \"1011\" => ledag <=\"1111100\"; when \"1100\" => ledag <=\"0111001\"; when \"1101\" => ledag <=\"1011110\"; when \"1110\" => ledag <=\"1111001\"; when \"1111\" => ledag <=\"1110001\"; when others => null; end case; end process; process(q2) begin

case q2 is

when \"0000\" => ledag1 <=\"0111111\"; when \"0001\" => ledag1 <=\"0000110\"; when \"0010\" => ledag1 <=\"1011011\"; when \"0011\" => ledag1 <=\"1001111\"; when \"0100\" => ledag1 <=\"1100110\"; when \"0101\" => ledag1 <=\"1101101\";

when \"0110\" => ledag1 <=\"1111101\"; when \"0111\" => ledag1 <=\"0000111\"; when \"1000\" => ledag1 <=\"1111111\"; when \"1001\" => ledag1 <=\"1101111\"; when \"1010\" => ledag1 <=\"1110111\"; when \"1011\" => ledag1 <=\"1111100\"; when \"1100\" => ledag1 <=\"0111001\"; when \"1101\" => ledag1 <=\"1011110\"; when \"1110\" => ledag1 <=\"1111001\"; when \"1111\" => ledag1 <=\"1110001\"; when others => null; end case; end process;

end a;