HELLO ALL

我想寫一佪RGB LED 控制程式如下 ,其中pwm 部分一直有錯(紅色),是否有人可指導,其中Data_Value 我會從一counter 讀出color sensor 謮值再和Set_data_R 比較,再做PWM調變

謝了

ibrary IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
use work.user_pkg.all;
---- Uncomment the following library declaration if instantiating
---- any Xilinx primitives in this code.
--library UNISIM;
--use UNISIM.VComponents.all;
entity PWM_GEN is
Port ( clock : in STD_LOGIC;
Reset : in STD_LOGIC;
Data_Value : in STD_LOGIC_VECTOR (7 downto 0);
PWM : out STD_LOGIC);
end PWM_GEN;
architecture Behavioral of PWM_GEN is
SIGNAL reg_out : std_logic_vector (7 downto 0);
SIGNAL cnt_out_int : std_logic_vector (7 downto 0);
SIGNAL pwm_int : std_logic;
SIGNAL rco_int : std_logic;
SIGNAL set_data_R : std_logic_vector (7 downto 0);
SIGNAL A : std_logic_vector (7 downto 0);
SIGNAL B : std_logic_vector (7 downto 0);

begin
process (clock,reg_out,reset)

BEGIN
IF(rising_edge (clock)) then
A <= Data_value;

END IF;

END process;

process (A,B)
BEGIN
B <= "10000011";--setting PWM duty R LED=%/Hz--
set_data_R <="11000000"; --set R LED pluse data--

if (set_data_R < A) then
B <= B-1 ; --If set data > counter data then increase PWM duty --

ELSE if (set_data_R > A) then
B <= B 1 ; --If set data < counter data then decrease PWM duty --

ELSE B <= "10000011";

END if;
END if;
if (B < "00000011" )then
B <="00000100";
END if;
if (B > "11111110") then
B <="11111100";
END if;


reg_out<= B;
END process;

process(clock,cnt_out_int,rco_int,reg_out)
BEGIN
IF(rco_int = '1') then
cnt_out_int <= reg_out;
ELSIF rising_edge(clock) then
IF (rco_int ='0' and pwm_int='1' and cnt_out_int < "11111111") then
cnt_out_int <= INC(cnt_out_int);
ELSE
IF (rco_int='0' and pwm_int='0' and cnt_out_int >"00000000") then
cnt_out_int <=DEC(cnt_out_int);
END if;
END if;
END if;
END Process;
Process(cnt_out_int,rco_int,clock,reset)
BEGIN
If (reset = '0') then
rco_int <= '1';
elsif rising_edge(clock) then
IF ((cnt_out_int="11111111") or (cnt_out_int ="00000000")) then
rco_int <='1';
else
rco_int <='0';
END if;
END if;
END process;
Process(clock,rco_int,reset)
BEGIN
IF (reset = '0') then
pwm_int <= '0';
elsif rising_edge(rco_int) then
pwm_int <=NOT(PWM_int);
ELSE
pwm_int <=PWM_int;
END If;
END process;
PWM <= PWM_int;


end Behavioral;

編輯記錄

B這個signal multi access.

if (set_data_R < A) then
B <= B-1 ; --If set data > counter data then increase PWM duty --

ELSE if (set_data_R > A) then
B <= B 1 ; --If set data < counter data then decrease PWM duty --

ELSE B <= "10000011";

END if;
和
if (B < "00000011" )then
B <="00000100";
END if;
if (B > "11111110") then
B <="11111100";
END if;
同時出value比B
你的program我看不明白,但你的想法應該錯了
首先PWM counter的clock和Load PWM value的clock應該是不同的
例如
L是指load,-指不動作,用8-bit PWM
L------------|L------------
256次count up|256次count up
如果count up>L就出0其它時候(count up<=L) 就出1,就可以出到這樣的PWM
L(10)-----------------------|L------------
1,2,3,4,5,6,7,8,9,10,11,....|256次count up
0000000000000000000011111111|PWM output
其實一個PWM只要
1)1個Latch(儲存PWM value)
2)1個counter
3)1個比較器
就做到了