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LIBRARY ieee;
9 G" M& n3 [, hUSE ieee.std_logic_1164.all;
: \# l# s% L' x3 zUSE ieee.std_logic_unsigned.all;
3 s; X/ p, G# e) U j0 ~ENTITY counter_backwards60_seg2 IS/ l2 X/ D: k8 F) [8 S" K4 A
PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;6 Q5 [% N ~/ z3 l; X# w" c
Ring : OUT STD_LOGIC;
4 `) S' K0 t6 c- {5 ]8 p8 D/ U3 p Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ; 7 N: S6 g! X+ {, D) \. B
END counter_backwards60_seg2;
7 j$ z. |# ^ T7 I2 D3 D1 gARCHITECTURE arc OF counter_backwards60_seg2 IS% I2 g ] E1 N" s
BEGIN
3 i1 d3 H* |; q% x2 H8 v PROCESS (Clk)
; r; d6 `1 H2 Y' z' z" h VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);
, b/ m. i) n. J; k' I VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);, t. N F. J. _5 [( K) J% X
BEGIN
! Q, j% H0 h! a; |8 Q- j% d IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";0 s( r+ T$ ]& F. L5 ]; b
ELSE IF (Clk'event AND Clk='1') THEN 5 Q2 ~5 O o: }- e" }! `* {. W4 L
IF Load='0' THEN imper1:="0110"; imper0:="0000"; 6 X; {1 M7 s+ I+ g$ z7 H0 J/ H9 D
ELSIF Ena='1' THEN ?7 y5 Y9 P! Y; W8 w& o
IF (imper0="1001" AND imper1="0101")THEN" @! B# V% r. |
imper0 :="1000"; 4 ]( S& k3 M! m( f. j* Y
ELSIF imper0 >"0000" THEN imper0 := imper0-1;, ?2 _# _4 |2 u' \5 g H* P& I
ELSE imper0:="1001";
; G2 [& L& e1 Q5 K% E IF imper1 >"0000" THEN imper1 := imper1-1;9 n4 g+ j( {; N
ELSE imper1:="0101"; 7 o. L9 |7 g/ x, E: f7 O# g
END IF;
& w# l" u, J+ n; J* ?( N# U END IF;
. w; ]& I7 {# c3 o END IF;4 @, J" }% i K7 f1 D
END IF;
5 R8 |* G/ k$ c/ e% W END IF;
) {$ O3 Q; g2 F) z) {% f% dQ0 <= imper0; Q1 <= imper1;
7 q# v: ~) y. HRing <= not(imper0(0) or imper0(1) or imper0(2) or imper0(3) or imper1(0) or imper1(1) or imper1(2) or imper1(3)); * w. B9 n7 y0 [+ n9 t/ q% c# f
END PROCESS ;
2 ~, M5 B$ y" G3 @END arc;
; U4 E# ^9 K/ c( W/ ?' |
9 G: ~1 u1 l# s* R' @& a上面是我的倒數60秒程式
, U0 I" C- q+ M& U* j5 t小弟不才
- ]1 n2 z, ^2 w7 I8 R不知道怎寫停止
' R& ?& ~% t9 C- [! r# h只要數1次60就好 |
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