基于VHDL的呼吸灯的问题

军霸之上

[mw_shl_code=c,true]LIBRARY ieee; USE ieee.std_logic_1164.all; USE ieee.std_logic_unsigned.all; ENTITY huxideng2 IS PORT( RESET :IN STD_LOGIC; CLK :IN STD_LOGIC; led :OUT STD_LOGIC); END huxideng2; ARCHITECTURE PWM OF huxideng2 IS SIGNAL Period_us,Period1uS, Period1mS, Period1S: STD_LOGIC;--the period of the calculater signal counter:integer range 0 to 300; signal pwm:integer range 0 to 64; BEGIN -- Clock PROCESS( RESET, CLK, Period_us, Period1uS, Period1mS ) VARIABLE Count : STD_LOGIC_VECTOR(5 DOWNTO 0); VARIABLE Count1 : STD_LOGIC_VECTOR(9 DOWNTO 0); VARIABLE Count2 : STD_LOGIC_VECTOR(9 DOWNTO 0); VARIABLE Count3 : STD_LOGIC_VECTOR(2 DOWNTO 0); VARIABLE pwm: STD_LOGIC_VECTOR(7 DOWNTO 0); BEGIN --Period: 1uS IF( RESET = '1' ) THEN Count := "000000"; ELSIF( CLK'EVENT AND CLK='1' ) THEN IF( Count>"110000" ) THEN Count := "000000"; -- 110000:48 50/50M = 1us count from 0 to 48 ELSE Count := Count + 1; END IF; Period1uS <= Count(5); END IF; --Period:0.1us IF(CLK'EVENT AND CLK='1') THEN IF(Count3>"101") THEN Count3 :="000"; ELSE Count3 :=Count3+1; END IF; Period_us <=Count(2); END IF; --Period: 1mS IF( Period1uS'EVENT AND Period1uS='1' ) THEN IF( Count1>"1111100110" ) THEN Count1 := "0000000000"; -- 1111100110:998 1000*1us = 1ms count from 0 to 998 ELSE Count1 := Count1 + 1; END IF; Period1mS <= Count1(9); END IF; --Period: 1S IF( Period1mS'EVENT AND Period1mS='1' ) THEN IF( Count2>"1111100110" ) THEN Count2 := "0000000000"; --like above ELSE Count2 := Count2 + 1; END IF; Period1S <= Count2(9); END IF; END PROCESS; PROCESS(Period_us) --The Period of the pwm BEGIN if rising_edge(Period_us) then if counter=300 then counter<=0; pwm<=pwm+1; if pwm=64 then pwm<=0; end if; else counter<=counter+1; end if; end if; END PROCESS; process(Counter,pwm) begin if counter<pwm then led<='1'; else led<='0'; end if; end process; END PWM;[/mw_shl_code]

为什么我运行最后就卡在了led<=0那里啊，求高手指点指点

正点原子

帮顶。。。。。