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LIBRARY ieee; $ J$ o) C8 h, W: u8 P1 ^# c
USE ieee.std_logic_1164.all;: ^% i1 h; b; J7 S
USE ieee.std_logic_unsigned.all;
m/ ?( o) y) z" r" MENTITY counter_backwards60_seg2 IS
' b$ Y+ f% D' b3 [& o/ `; a: B PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;9 c( p. j+ P" {/ {' m
Ring : OUT STD_LOGIC; ; g* z" h5 F1 q( c# K4 d
Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ;
0 x; G; h: D3 ^3 \; fEND counter_backwards60_seg2;# g- C) b5 |. W' o" t( i
ARCHITECTURE arc OF counter_backwards60_seg2 IS
/ U$ I; e+ X# n A BEGIN
+ J$ x0 }$ w( I. ` PROCESS (Clk)
2 a+ z: Z& t7 G: ]$ [ VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);
! i: x2 q7 J3 r! I VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);
: m z" P S% N# z& P" P! V. | BEGIN
7 E& U- N( i# o% w# Q IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";# k0 S! g) ?9 n1 y/ R
ELSE IF (Clk'event AND Clk='1') THEN " J3 P$ D( S! w5 W% T9 ?4 ]$ M
IF Load='0' THEN imper1:="0110"; imper0:="0000";
$ \' x" w) H1 w* U ELSIF Ena='1' THEN' h: n& L X' W7 [ |
IF (imper0="1001" AND imper1="0101")THEN
6 u9 A. j) F( i7 Q3 e: Q imper0 :="1000"; ( R1 W3 B+ H% A" _- k8 @
ELSIF imper0 >"0000" THEN imper0 := imper0-1; {% I/ ?& b+ X, Y) n$ B, t: S
ELSE imper0:="1001";) ^8 Z& Z& x- H
IF imper1 >"0000" THEN imper1 := imper1-1;, {; V, J( k1 R% g. T
ELSE imper1:="0101"; / q6 V0 t; W/ C; B1 ~8 ]1 z# J4 ~* `
END IF;- @% P5 i, c/ _ R2 Y& Z. G
END IF; ! j0 l3 ^0 @/ F/ l: V5 _! U8 b; Q- b
END IF;
3 C t8 b( J3 e! M! {8 j END IF;
% @ [3 I4 K4 A$ s+ d: } END IF;
9 C; o; D4 [5 q: F! {8 UQ0 <= imper0; Q1 <= imper1; - n/ l4 W6 b8 z, {# w* X2 b% N* c2 E5 Q# V
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)); & P8 D1 o* d/ p$ V) z+ [
END PROCESS ;9 k# Y$ ^1 S9 i( O* Q
END arc;
' p9 l$ J6 s2 D2 Z* { Z- W$ K! p! p8 \+ t. ?' ^% k
上面是我的倒數60秒程式) @9 T3 T! u! b1 z3 [
小弟不才2 \1 g. c, x! m# h! q. b
不知道怎寫停止
% A9 v$ c' N$ Y4 }( k- n只要數1次60就好 |
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