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LIBRARY ieee;
9 ]# k' P8 ]. B' T1 ~* aUSE ieee.std_logic_1164.all;( s6 \2 ]6 r$ A, V4 r3 z
USE ieee.std_logic_unsigned.all;
8 i Q8 I2 { M+ z, c; I& {ENTITY counter_backwards60_seg2 IS& n1 x* v4 t; z3 Q+ R3 m/ d
PORT(Clk : IN STD_LOGIC;
E# a0 e/ o0 U Q0,Q1 : OUT STD_LOGIC_VECTOR(3 downto 0)) ;
& C3 |: u/ ^7 ?7 ]5 |( rEND counter_backwards60_seg2;4 b% ?/ K5 S) ?' I- E
ARCHITECTURE arc OF counter_backwards60_seg2 IS' E7 K1 M& @) p3 y7 x2 u1 @( Z
BEGIN5 n: Y' k$ Y8 P: m6 G
PROCESS (Clk)
9 S( j4 ^/ W; b. P: Z2 @* A VARIABLE imper0 :STD_LOGIC_VECTOR(3 downto 0);: ]" A: Q: z9 v7 w+ o J- q) ^
VARIABLE imper1 :STD_LOGIC_VECTOR(3 downto 0); . Q* }% O- a0 y m! C; w1 |6 G7 t
BEGIN
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IF (Clk'event AND Clk='1') THEN
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1 S3 O. t+ ^. U% X6 d IF imper0 >"0000" THEN imper0 := imper0-1;
- j- t$ J/ A. X1 t+ ?, s9 d2 W( l( g ELSE imper0:="1001";
+ Z+ G$ B% |8 A ~( P9 N f% K IF imper1 >"0000" THEN imper1 := imper1-1;
! X9 a5 l& ^& A* A ELSE imper1:="0101";
! X F! ~5 y0 W( u END IF;
, x9 @2 I w- w" ?) C END IF;
0 M7 [' e' i% Q9 w, P END IF; 4 O/ n6 F) @) |" q
Q0 <= imper0; Q1 <= imper1;
, b( H0 j$ O. s' g/ J END PROCESS ;
4 O9 v- Y3 X8 l, A0 |END arc;
; ^7 c& f; S8 C7 [以上我精簡了一些 也能跑模擬圖
/ ~# u( a1 g0 Y5 @* q. X8 B. {但現在重點是我該怎寫60→59→58...
. D s. e" G$ m! g# @- Y初始值60要怎寫...
) m' H! E& P# T1 w, i是要多2個input 然後給他一開始的值?; `; N" A, N- M1 ?( L
但要怎寫啊@@...
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