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LIBRARY ieee; ' w8 D# ~0 @0 D9 M2 g
USE ieee.std_logic_1164.all;' w: d1 `- s( I$ R) ]: P
USE ieee.std_logic_unsigned.all;2 H g$ P) N' f1 `8 m
ENTITY counter_backwards60_seg2 IS8 o( y$ P8 [0 u% _2 q: ^) ?
PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;
. C. K2 M8 J& i1 T Ring : OUT STD_LOGIC;
; v/ m- F/ Z# \3 U! M- ^0 u Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ;
- [" [& x. `: R( R* iEND counter_backwards60_seg2;
7 n" h: R, S& SARCHITECTURE arc OF counter_backwards60_seg2 IS
; w1 n4 k1 ?& O& X/ q BEGIN
! j1 U" w! a8 M$ L- N0 Z3 Q* K PROCESS (Clk)$ R0 k/ z6 k) N8 u: S- \
VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);
7 x: F) Y8 S6 ]/ h( d- N2 S) {7 o' t VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);
/ [! a% _ o2 j+ J; F& B BEGIN
( N o! S" ?0 ]' b IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";1 r4 T& d# r" @; e8 |
ELSE IF (Clk'event AND Clk='1') THEN 1 x/ d& k& Z& W/ L% p( v
IF Load='0' THEN imper1:="0110"; imper0:="0000";
4 P) [, l) A; A3 h" k, V5 _5 d ELSIF Ena='1' THEN
2 V7 ^3 [& W2 u IF (imper0="1001" AND imper1="0101")THEN: C* g8 F( ^ O5 c' h5 Y& x- }. M
imper0 :="1000";
p1 K, x/ W; b( D8 o5 B ELSIF imper0 >"0000" THEN imper0 := imper0-1;( T n1 \7 W5 U
ELSE imper0:="1001";
+ Q, i, c! o/ H v1 l7 r IF imper1 >"0000" THEN imper1 := imper1-1;
" m3 |4 g+ i* c( G ELSE imper1:="0101";
- M V; y. [* A, D' ^* K/ R END IF;8 `: O- S" i# g2 Z1 E
END IF;
" |/ c7 o0 P* _ G- d END IF;
0 N' r' B' `" a% t- y/ }8 x END IF;8 N- \% x& N1 z7 G# h
END IF;
/ J5 R% ~, {( K9 A# r1 g% wQ0 <= imper0; Q1 <= imper1;
8 S7 [& s6 y. R, ?5 r9 eRing <= not(imper0(0) or imper0(1) or imper0(2) or imper0(3) or imper1(0) or imper1(1) or imper1(2) or imper1(3));
2 \7 j* E$ [" C5 I END PROCESS ;
& `( p7 e% r; l5 S( m1 q, B) \END arc;* D! r# `: A+ G2 I
2 ~. N7 G' q0 M/ e) Q
上面是我的倒數60秒程式
; M- x1 R: i1 ]* C& k小弟不才1 g4 f, w! B% l5 B2 K
不知道怎寫停止
+ d! b4 \# i" W5 j# b0 z5 v7 z/ m1 u只要數1次60就好 |
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