我正试图在800x600的屏幕上实现一些“球”弹跳。我不完全明白如何让第二球在屏幕上移动。现在，它只是静止地停留在屏幕上的某个位置。
以下是我到目前为止所拍摄的照片。
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity pong is
Port ( myclk : in STD_LOGIC;
rgb : out STD_LOGIC_VECTOR (2 downto 0);
hs : out STD_LOGIC;
vs : out STD_LOGIC);
end pong;
architecture Behavioral of pong is
signal clk: STD_LOGIC;
signal horz_scan: STD_LOGIC_VECTOR (9 downto 0);
signal vert_scan: STD_LOGIC_VECTOR (9 downto 0);
signal vinc_flag: STD_LOGIC;
signal dx: STD_LOGIC;
signal dy: STD_LOGIC;
signal refresh_counter: STD_LOGIC;
signal posx: integer := 300;
signal posy: integer := 300;
signal color: STD_LOGIC_VECTOR (2 downto 0) := "111";
signal vinc_flag2: STD_LOGIC;
signal dx2: STD_LOGIC;
signal dy2: STD_LOGIC;
signal posx2: integer := 300;
signal posy2: integer := 300;
signal color2: STD_LOGIC_VECTOR (2 downto 0) := "001";
signal refresh_counter2: STD_LOGIC;
signal horz_scan2: STD_LOGIC_VECTOR (9 downto 0);
signal vert_scan2: STD_LOGIC_VECTOR (9 downto 0);
signal clk2: STD_LOGIC;
begin
-- Clock divide by 1/2
process(myclk)
begin
if myclk = '1' and myclk'Event then
clk <= not clk;
end if;
end process;
-- horizonal clock
process(clk)
begin
if clk = '1' and clk'Event then
if horz_scan = "1100100000" then
horz_scan <= "0000000000";
else
horz_scan <= horz_scan + 1;
end if;
end if;
end process;
-- vertial clock (increments when the horizontal clock is on the front porch
process(vinc_flag)
begin
if vinc_flag = '1' and vinc_flag'Event then
if vert_scan = "1000001001" then
vert_scan <= "0000000000";
refresh_counter <= refresh_counter xor '1';
else
vert_scan <= vert_scan + 1;
end if;
end if;
end process;
process(vinc_flag2)
begin
if vinc_flag2 = '1' and vinc_flag2'Event then
if vert_scan2 = "1000001001" then
vert_scan2 <= "0000000000";
refresh_counter2 <= refresh_counter2 xor '1';
else
vert_scan2 <= vert_scan2 + 1;
end if;
end if;
end process;
process(refresh_counter)
begin
if refresh_counter = '1' and refresh_counter'Event then
if dx = '0' then
posx <= posx + 1;
else
posx <= posx -1;
end if;
if dy = '0' then
posy <= posy + 1;
else
posy <= posy -1;
end if;
color <= "100";
end if;
end process;
process(refresh_counter2)
begin
if refresh_counter2 = '1' and refresh_counter2'Event then
if dx2 = '0' then
posx2 <= posx2 + 1;
else
posx2 <= posx2 -1;
end if;
if dy2 = '0' then
posy2 <= posy2 + 1;
else
posy2 <= posy2 -1;
end if;
color2 <= "001";
end if;
end process;
process(posx)
begin
if posx = 144 then
dx <= '0';
elsif posx = 734 then
dx <= '1';
end if;
end process;
process(posy)
begin
if posy = 35 then
dy <= '0';
elsif posy = 465 then
dy <= '1';
end if;
end process;
process(posx2)
begin
if posx = 144 then
dx <= '0';
elsif posx = 734 then
dx <= '1';
end if;
end process;
process(posy2)
begin
if posy = 35 then
dy <= '0';
elsif posy = 465 then
dy <= '1';
end if;
end process;
-- horizontal sync for 96 horizontal clocks (96 pixels)
hs <= '1' when horz_scan < 96 else '0';
-- vertial sync for 2 scan lines
vs <= '1' when vert_scan(9 downto 1) = "000000000" else '0';
rgb <= color when (vert_scan >= posy and vert_scan < (posy+50) and horz_scan >= posx and horz_scan < posx+50) or (vert_scan >= posy2 and vert_scan < (posy2+50) and horz_scan >= posx2 and horz_scan < (posx2+50)) else "000";
vinc_flag <= '1' when horz_scan = "1100011000" else '0';
end Behavioral;
答案 0 :(得分：2)
您的代码中似乎存在复制和粘贴错误。最后两个进程分别对posx2和posy2敏感，但您似乎正在更改第一个球的状态（dx和dy）。你不应该改变dx2和dy2吗？
此外，以下两条建议可让您的代码更具可读性：
不是将计数器声明为std_logic_vectors并将它们与位串文字（例如if vert_scan2 = "1000001001" then ...）进行比较，为什么不将计数器声明为整数？这将有助于使您的代码更具可读性。
不要在整个代码中使用“幻数”或硬编码文字（例如，在表达式if posx = 144 then ...中， 144 是一个幻数）。相反，使用有意义的名称（constant BALL_X_POS_MIN: integer := 144;）创建一个常量，并在表达式（if posx = BALL_X_POS_MIN then ...）中使用它。