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LIBRARY ieee;
6 F8 A. r7 s6 mUSE ieee.std_logic_1164.all;% i9 A9 U! D1 M9 ?! R) M5 C5 \) [
USE ieee.std_logic_unsigned.all;
- L1 Q* I' M- ]2 K7 R* MENTITY counter_backwards60_seg2 IS0 A& T8 `2 o5 s# W7 J( z5 \
PORT(Clrn,Load,Ena,Clk : IN STD_LOGIC;' |7 l. g5 K- r
Ring : OUT STD_LOGIC; 7 r+ U; a" |% f4 T
Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ; 7 R4 O% q2 F6 |
END counter_backwards60_seg2;- Y7 ~( Y2 S, _* l0 u4 l' I
ARCHITECTURE arc OF counter_backwards60_seg2 IS2 `" {! W3 c# L9 x& U0 o3 n
BEGIN) k/ k6 k: u: _5 M& D+ ?# A& _! [
PROCESS (Clk), M# ]( o- c) a$ @$ Q
VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);
7 J' j R) i" q" h' j2 Z) |: [ VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0);, t% K8 M/ w8 [: Z
BEGIN
2 }& V5 D- K) ]8 Q5 k4 c IF Clrn='0' THEN imper1 := "0110"; imper0 := "0000";1 s" E8 s: b9 o/ u
ELSE IF (Clk'event AND Clk='1') THEN , m6 Y7 \7 P' S0 |% m* O; [+ |* W
IF Load='0' THEN imper1:="0110"; imper0:="0000";
' I& _ h# w- W4 q ELSIF Ena='1' THEN
+ _& O' |5 u) n2 Y1 Q+ K; m IF (imper0="1001" AND imper1="0101")THEN
( G$ x" h' s& D6 O1 B$ \/ Z imper0 :="1000"; 2 V5 I9 T+ z' e9 `6 P% e! S
ELSIF imper0 >"0000" THEN imper0 := imper0-1;8 b& |5 m& O! }
ELSE imper0:="1001";
- T: G& R0 J: n) b8 d: D/ N IF imper1 >"0000" THEN imper1 := imper1-1;
+ j% ^! H4 Y( \$ N" Y: A. k ELSE imper1:="0101"; 8 e, `6 {: j( d. _ Z; e1 y
END IF;
4 o. L+ h1 y4 y END IF; - Z% R- C: h* ?- T; ~4 [
END IF;
; `7 m' \/ u: a8 v4 U5 i) p END IF;
) P5 N$ J" ~$ x) p# H/ H END IF; . @; r q; y4 N7 p8 o4 L2 G
Q0 <= imper0; Q1 <= imper1; 7 j! ?& U3 |4 a" {" a9 r
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));
1 O9 u9 Y6 S" ^ END PROCESS ;
4 f, P' Q0 z" @, sEND arc;1 W; e1 j: h8 X. r' G' R0 i+ n) S
3 P/ k H* `+ n; `9 m. v上面是我的倒數60秒程式* l! N4 |; R- N8 {; F
小弟不才
: f `) \# [# N不知道怎寫停止
' }7 h9 E" ^' F4 u7 ]只要數1次60就好 |
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