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Key function
) i, Q& Y/ }' \* B, u7 b按鍵開關 第一次 on時,開始計時。
1 ` B& q4 E V4 A 第二次 on時,停止計時。
- r. R* n! D' A2 R r 第三次 on時,開始計時。% T3 P1 R: B1 i! |+ ?3 S0 X
未 synthesis,請自行 debug........ 3 b/ O- N d& e Z% n: R0 E
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LIBRARY ieee;
; `0 _9 C! P8 x* N D; b* CUSE ieee.std_logic_1164.all;+ W) K5 ~5 M, N8 X/ k
USE ieee.std_logic_unsigned.all;5 n4 V7 j. G) u4 }: q& K) z
ENTITY KeyFunction IS* o+ u6 G9 d" ~5 Y3 H
PORT(CLK,
4 O5 U: R9 x @. M% h PB,
" E/ J# C3 P) Z* f) H1 R( X RSTn : IN STD_LOGIC;
! n) h9 v% C( v! D) a2 V START_COUNT,
& I! d' v/ W- N- h- E6 Y0 t PAUSE
6 d" M( t0 ^9 G6 N, \, J! }6 E : OUT STD_LOGIC 8 @" F) x: L$ Q" ~5 h$ y
);
; H# D' Q! N: k% l6 |END KeyFunction;
{, [% j# e/ S9 k8 M! X2 X+ mARCHITECTURE arc OF debounce_v IS
3 n% J0 L8 C( [; mSIGNAL currently_state : STD_LOGIC_VECTOR(2 downto 0);, @- o; i1 f. ^) F0 F# \
signal pb_reg,debounce_counting,debounce_end : std_logic;: |. h! m1 I s9 s
signal debounce_counter : STD_LOGIC_VECTOR(15 downto 0);
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constant debounce_time : STD_LOGIC_VECTOR(15 downto 0):= "0000000000000000";
. i3 f! w. v2 Q$ y, XBEGIN
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8 w/ j6 s* c& N8 D: J3 s--============================================================
6 n/ P! m+ F& K-- get key push state. ( active high)+ f( @" J+ s. d$ P' G
--============================================================
3 C7 S, O/ `; \9 m' u$ R1 | PROCESS (CLK,RSTn,PB,pb_reg,debounce_counting,debounce_end)
3 E9 G% A# Y& m, {+ h b BEGIN
1 g* a( o5 i1 F: Q- V if( RSTn = '0') then
+ T" d6 t$ m2 s4 { pb_reg <= 1;9 @% u" A$ {/ x* F
elsif( CLK 'event and CLK ='1')then" T5 B: C6 ~# T7 G
if( PB='1' and pb_reg ='0')then
9 ^, p, ~% M- B: n9 [% h2 `+ D debounce_counting <= '1'; c, w( s& Z z# C7 D
elsif( debounce_end = '1')then
1 S! _' [% e) w& P3 P8 g! ]: d6 `% E debounce_counting <= '0'; 0 l, E, Y! W ?, e$ D$ Q' X
else
! m; T! {* a- q1 q debounce_counting <= debounce_counting;! t6 ~! S; ^6 F' }3 X
end if;) q0 a. K1 j# X% ]
pb_reg <= PB;
: b' F5 N; q o) |/ X8 b$ R2 O- Q end if; |
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