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LIBRARY ieee;
: h/ L! I7 {1 }, }. g0 i+ ]USE ieee.std_logic_1164.all;
6 k6 M0 V0 `) }/ mUSE ieee.std_logic_unsigned.all;
% ]1 I$ ?& k8 T. ]' _; WENTITY counter_backwards60_seg2 IS
/ i8 W0 I6 X+ }# J7 g PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;5 z4 i. F, x4 L! }2 K
Ring : OUT STD_LOGIC;
$ ~: W% Y% ?, K( v4 h Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ;
' @0 ? c* N* \END counter_backwards60_seg2;3 A! J# L, t8 @( [) Y* h
ARCHITECTURE arc OF counter_backwards60_seg2 IS+ h3 t7 ^. }, Z% Y4 ?
BEGIN
: }9 t6 x n5 `* H# ~ PROCESS (Clk)
5 T# S; j! j; [$ \! @1 Q) ^0 f; D VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);
1 B/ l1 u/ u2 h5 D VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);5 ^: r$ A+ }) P( c
BEGIN
: e& e3 l% |# Q j; C0 Q IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";
+ |1 j* \, O* ~) f ELSE IF (Clk'event AND Clk='1') THEN
+ e4 C% |4 a [( l IF Load='0' THEN imper1:="0110"; imper0:="0000";
) t" L: F& I( {: e d ELSIF Ena='1' THEN6 T& a/ M$ F0 O$ B8 M
IF (imper0="1001" AND imper1="0101")THEN
3 j1 Y M! i& ?. ?# G, J imper0 :="1000"; 5 Y/ l+ ?/ j, S
ELSIF imper0 >"0000" THEN imper0 := imper0-1;
{! ~. L) } W) W' U* P ELSE imper0:="1001";! e4 N7 G/ v0 T3 o" l& e3 {
IF imper1 >"0000" THEN imper1 := imper1-1;! b3 d" `3 S0 s! [4 q
ELSE imper1:="0101"; 0 L' Z% F0 H0 ?3 @( J9 ]
END IF;
$ D8 }* B; h# F' ^+ [+ o END IF; % S8 x1 s5 V. ~
END IF; d S3 Y8 G3 }. m% |8 p$ j: r
END IF;: i( ^" Y6 c7 x7 ~) H
END IF; . m% W3 R# U: e
Q0 <= imper0; Q1 <= imper1;
4 A( V( C! |5 E- U/ @2 bRing <= not(imper0(0) or imper0(1) or imper0(2) or imper0(3) or imper1(0) or imper1(1) or imper1(2) or imper1(3)); , B+ D) d( M/ @8 e& e/ Q
END PROCESS ;
4 u* p% N" c: q6 cEND arc;" y0 g$ D9 K$ {( I4 d# Y
8 }2 l6 u/ N) j/ e, U( ], ?; A
上面是我的倒數60秒程式
; \' d7 K: [% ^% v9 V/ L t! V小弟不才: j8 P u r3 L3 s
不知道怎寫停止
" x% m3 j2 Y! I: I只要數1次60就好 |
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