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LIBRARY ieee;
2 {& f4 Y1 {, u/ j/ ?9 P1 f' UUSE ieee.std_logic_1164.all;
( Y: ?2 `' ^( hUSE ieee.std_logic_unsigned.all;
S1 i4 c& F+ X; [$ iENTITY counter_backwards60_seg2 IS. F) P( g/ u. f+ }# O; Y! ^
PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;- p( ^) Q* D Z6 y9 r
Ring : OUT STD_LOGIC; . Q H0 [1 X1 o0 g; q
Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ; 2 @; W5 [' K8 i% K
END counter_backwards60_seg2;$ A0 c( _7 {. q+ b& h; _) N' _
ARCHITECTURE arc OF counter_backwards60_seg2 IS
, k9 Z0 W ~6 [- W9 ` BEGIN
& B# y* k. b" }& q; s( M PROCESS (Clk)! O6 I7 I+ {4 O% t
VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);# \) h1 X. e- o& H3 J! d6 i
VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);
/ q, y7 n$ o; ~+ y6 ] BEGIN) c- i8 ^" ?) f# ~3 S* t
IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000"; R' k+ N* w; h: P# m! B' }
ELSE IF (Clk'event AND Clk='1') THEN
, q6 v- V5 }& o: o4 P3 ~. L0 X IF Load='0' THEN imper1:="0110"; imper0:="0000";
, F/ N( T2 u* [+ ~& D; e% Z8 q# I ELSIF Ena='1' THEN
0 [; d- d% i' M2 x" A IF (imper0="1001" AND imper1="0101")THEN: A- _& ?- ]& L# Z% N& {
imper0 :="1000"; , C" c; _+ X3 F W( n; G
ELSIF imper0 >"0000" THEN imper0 := imper0-1;! X, l+ N( F; W) W0 G. A
ELSE imper0:="1001";* t# f+ A. Z, ?$ G0 S: ^' q& W
IF imper1 >"0000" THEN imper1 := imper1-1;7 a4 e$ I/ a6 J* F
ELSE imper1:="0101"; . j1 T" ~+ u" }) u4 o+ t* `# W$ |
END IF;
4 H; ?+ w; O5 e( H* k- W END IF;
& o7 C* A* ^$ C- F* g6 N# S+ A END IF;
5 Z" U) o% r) k7 T8 q END IF;+ d' r! _- x- [- _' {) `9 X
END IF;
3 `# O/ O4 N W7 ^1 G+ cQ0 <= imper0; Q1 <= imper1; 4 v% O, c6 R8 o$ Z5 F* o
Ring <= not(imper0(0) or imper0(1) or imper0(2) or imper0(3) or imper1(0) or imper1(1) or imper1(2) or imper1(3));
* L) U+ Q$ f& y- d1 m; k END PROCESS ;% d4 z! K6 @5 i! j5 S$ q
END arc;; a- h W* P8 `3 Y
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上面是我的倒數60秒程式
& E, \, p# q' b- [! [# L小弟不才
4 {# F" o) ?2 A7 a% i/ R不知道怎寫停止
7 g9 V6 b9 { Y2 L |. ?4 p只要數1次60就好 |
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