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LIBRARY ieee; 7 W. z6 t) H I! x, R3 z
USE ieee.std_logic_1164.all;* ]# d5 c; k: U( h- Y
USE ieee.std_logic_unsigned.all;
+ t, g$ P6 O% U& ~0 T3 B/ Y b' ]ENTITY counter_backwards60_seg2 IS
1 r* j' H1 A R& B8 u. b, r PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;; _& z& z4 d2 y6 a0 p% U
Ring : OUT STD_LOGIC; : ?5 ^; Q( Q7 s( q% _
Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ;
. E& t& G( X4 }! S! |, G2 EEND counter_backwards60_seg2;
) ?4 J A, H6 a/ c* a- KARCHITECTURE arc OF counter_backwards60_seg2 IS* |6 q0 I. _8 q) h
BEGIN
, W7 v% a5 a- P" U0 A, p$ u PROCESS (Clk)
* s3 w. l4 n, k VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);
: j) S* x4 R6 J4 R3 Y' `3 [2 A VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);( L! `* A, H9 X4 j4 |
BEGIN9 x7 v4 C, l1 h# e( c. X- U* [7 q
IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";
! E, a$ u& Q1 u7 w3 ` ELSE IF (Clk'event AND Clk='1') THEN , h: F& P5 z# t1 G. ~9 i4 Z
IF Load='0' THEN imper1:="0110"; imper0:="0000"; 7 W5 m6 ^. B8 C" @) y2 K3 @$ c
ELSIF Ena='1' THEN
! I7 H0 G D {( y IF (imper0="1001" AND imper1="0101")THEN# i3 M, U/ [/ A' m
imper0 :="1000";
/ C* U- l, u o0 P. }4 j5 C! N1 H( C( q ELSIF imper0 >"0000" THEN imper0 := imper0-1;
+ c r& o) J) v3 ? ELSE imper0:="1001";' B; q+ P# R2 t8 i' G' c, t
IF imper1 >"0000" THEN imper1 := imper1-1;
7 I% V8 P* N+ V, M* A6 @ ELSE imper1:="0101";
: ~/ h- B; o: p3 ^" k4 o8 `+ x" G END IF;
/ |3 Q# f" V r! }+ Z7 S8 F, |% w END IF;
2 u! d! [. z+ }: c! o END IF;. G* y6 p7 i6 H2 B4 Z$ S
END IF;
: N; i9 a/ Z( N7 d( n END IF;
% y% A( N, d) |. V5 M% EQ0 <= imper0; Q1 <= imper1;
7 W/ k |* q, u8 V$ vRing <= not(imper0(0) or imper0(1) or imper0(2) or imper0(3) or imper1(0) or imper1(1) or imper1(2) or imper1(3));
, G- y! G& M. ^6 o( e7 y END PROCESS ;
: w) K5 a: n+ F+ U u) N; V, V! YEND arc;
. i* }; b. w8 s6 g
* _$ {+ U: d! o+ R% g上面是我的倒數60秒程式+ [9 f! q- G3 @: Y+ P) {
小弟不才 b/ J" G% }4 K8 ~
不知道怎寫停止
, u6 T O2 b. X. L5 z只要數1次60就好 |
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