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LIBRARY ieee; 9 M2 d- w5 n" f* ~
USE ieee.std_logic_1164.all;& i8 Y' u) [* z9 d
USE ieee.std_logic_unsigned.all;2 C5 g0 h2 K% K' q
ENTITY counter_backwards60_seg2 IS; [1 a; u/ X6 V" w; p$ j2 g6 s
PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;
3 K" G2 c+ ]. F8 n3 K0 W Ring : OUT STD_LOGIC; # x) F- n0 ?+ J
Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ; 1 S4 N9 B: J& C1 J
END counter_backwards60_seg2;
/ K; }1 o. {. x, n% m$ {ARCHITECTURE arc OF counter_backwards60_seg2 IS* u9 @( n+ Q" o) h
BEGIN
' e# d& c4 W) M) B. Y PROCESS (Clk)! I" m7 }4 Z% |) v" Z8 G& G
VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);9 ]+ \6 V4 A7 ?7 d9 N) U" _7 d8 J
VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);
. n+ X1 a* S$ w: d BEGIN7 b* p6 I3 o! J$ V n
IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";
! Z' _* r2 ]+ f4 G ELSE IF (Clk'event AND Clk='1') THEN " n) Q8 C9 j9 R' P# Q5 }
IF Load='0' THEN imper1:="0110"; imper0:="0000"; ; l3 t. O7 c4 `
ELSIF Ena='1' THEN
0 X* Z2 V& }7 g1 h, O3 J2 P+ H4 f% ?2 y IF (imper0="1001" AND imper1="0101")THEN+ T. [- M) B" t! ~' k3 g4 F& D
imper0 :="1000"; . y9 U" V0 W* n8 g
ELSIF imper0 >"0000" THEN imper0 := imper0-1;$ z! Z( K+ P$ H) ~2 z! a
ELSE imper0:="1001";
P* n9 z" v2 w, i2 f/ P. w# B4 Q IF imper1 >"0000" THEN imper1 := imper1-1;
8 s) p! B8 U5 v- K1 ~ i4 U* i ELSE imper1:="0101"; 6 a! s8 N) T2 F* g% V* C
END IF;
2 Z+ S$ V, o) `9 B/ |0 u END IF; # ^; ~( N; ?9 U, G
END IF;4 n4 O. s: F" j, o4 ]% s- _& r
END IF;
, a1 X; O5 u, A+ V( E" h- G P END IF;
w4 U' ^2 @9 |0 l0 }+ F0 G# d# ZQ0 <= imper0; Q1 <= imper1;
/ h( @5 ^0 J7 \8 O6 W7 g) s' _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));
7 e# w9 ?6 i+ Y1 e/ h END PROCESS ;8 b& d8 E& y0 j; u$ C0 L
END arc;
. T' @) B# g" f. z) W; c
. H/ c( l3 K, i# ^4 ?/ Q1 Q6 c上面是我的倒數60秒程式- o- L1 V i- s4 U+ q r
小弟不才( x! w9 v6 {- U _+ J
不知道怎寫停止. W" N. e- ~& R& t5 ~! V' ^
只要數1次60就好 |
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