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LIBRARY ieee; : y- A; r) D, Z( ^+ i# @
USE ieee.std_logic_1164.all;% M; {1 H, O) G" k
USE ieee.std_logic_unsigned.all;
4 o4 O0 F7 R* q9 \' r4 {0 N& YENTITY counter_backwards60_seg2 IS# l) Q6 K& T: T$ @# U D
PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;- ^, @: P/ P; k# ^; U) a
Ring : OUT STD_LOGIC; ' _' a* N" R# l. |' I$ {% J0 `
Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ; : C% P2 T$ p9 a+ u9 l* d0 G+ P
END counter_backwards60_seg2;4 Z' B# O: A r' u% A: k9 v5 m: y
ARCHITECTURE arc OF counter_backwards60_seg2 IS
1 B, Z0 Y# b' N* J5 m BEGIN; P, B: F/ [- }8 v
PROCESS (Clk)
( ?1 E9 x' }" g# \ VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);( k j5 O& s' J1 p
VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);
( M) U( }* r! F6 _ BEGIN* D+ ?' Y+ e: ~) s) ?
IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";0 t% p2 k% M6 ]# I) ?! V. n
ELSE IF (Clk'event AND Clk='1') THEN
& e% h4 N4 G e3 ]- ] IF Load='0' THEN imper1:="0110"; imper0:="0000";
; D$ g0 i8 z7 C- l; o8 Y ELSIF Ena='1' THEN. v7 s# }9 d9 S1 I& K+ J
IF (imper0="1001" AND imper1="0101")THEN
6 i& m2 C$ O9 `: ~+ n! p( r imper0 :="1000";
. W8 G0 `3 Y! I8 n- h ELSIF imper0 >"0000" THEN imper0 := imper0-1;
; t0 g5 ~- }& N- l, u/ t ELSE imper0:="1001";/ M/ u; `/ V% c; j0 A4 K
IF imper1 >"0000" THEN imper1 := imper1-1;
; ] Y$ W) n4 J! b% U ELSE imper1:="0101";
$ Y: g3 z+ C; A% j8 m! ]! P END IF;6 ]5 M4 Y( S/ ^( i8 f8 ~
END IF; " J- Q# X/ U* z/ D N
END IF;
2 b1 [0 X: m8 F% q END IF;
! r" M. [# O8 ^- y( U END IF; $ A4 B0 z! [# P' @
Q0 <= imper0; Q1 <= imper1; # k+ j! N+ S3 `) @1 H
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)); , c' a% O; O* D L
END PROCESS ;
/ ]# G& k0 [0 F( v. k' I& X$ lEND arc;
6 M/ o7 s6 X1 Q* e3 [! @
7 o1 i' z* n9 x8 v \上面是我的倒數60秒程式" L, o. U7 r6 ^1 p: M% r6 }! y
小弟不才- p# o8 B1 o: V( X x
不知道怎寫停止
" I* Y9 P# U$ a u: E( z5 | z2 Y只要數1次60就好 |
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