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3#
樓主 |
發表於 2008-5-18 17:13:16
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只看該作者
恩~是的~我是要把它除到1HZ因為實驗器材的內部震盪晶體為40MHZ
' k) V6 y1 ]; R3 B0 B8 V除完1HZ接上計數器這樣~下面是我後來又改的><" 難道精準式除頻有很多種方法做??8 k/ K& K) a4 b: u1 V
entity clk_95 is
; J9 V" U! q& ^# |1 I8 s; a: w# ? Port ( clk40 : in STD_LOGIC;
1 i: v3 i p5 s' f+ R: m+ @6 W enable : in STD_LOGIC;
, S' _* f( n9 A switch : in STD_LOGIC; k2 g' a1 Q0 Z
a,b,c,d,e,f,g,p : out STD_LOGIC;7 ?! V; k6 g; C7 C0 R
SEL : OUT STD_LOGIC_VECTOR (5 DOWNTO 0));$ D+ z. {' r& k/ f+ z/ z+ A1 M
end clk_95;
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, L# A- C. j2 J/ w1 q5 rarchitecture Behavioral of clk_95 is! P; c/ u' \7 v4 V$ `- j" V
signal clk1 : STD_LOGIC ;
8 ^8 V8 |" B* C2 k6 t- z* t# hsignal cnt : STD_LOGIC ;
; ?9 t) M$ s$ a4 i& O; zsignal x1 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);9 U7 i9 `4 ?1 \9 D
signal x2 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);
, @# v9 p/ F' p g' Jsignal count1 : STD_LOGIC_VECTOR (3 DOWNTO 0); l+ y+ l9 \( L' A% e1 w
signal count2 : STD_LOGIC_VECTOR (3 DOWNTO 0);
6 A5 H* i0 A# rsignal y : STD_LOGIC_VECTOR (7 DOWNTO 0);8 Q7 m3 _. e! l4 ]7 o
begin. `% m& T3 W( A
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process(clk40)4 ~% r+ F# b8 I0 m& x
variable cnt:integer range 0 to 39999999;% K: [2 G2 K2 m/ P) C
begin
" s5 A; \- |# W% n/ `! ?; R) t) l2 [+ X if clk40'event and clk40='1' then
2 T5 A8 S# Q# B8 V9 B) E% {7 w: h if cnt<20000000 then1 T2 R3 R; s( |8 f/ y
cnt:= 0 ;2 w& i% b8 v; J9 Z U; e( X2 I
else
2 n- P- x M& |5 \% y6 r2 P3 G cnt:= 1 ;. k5 g8 N3 G2 V/ ~4 m8 A
end if;! N0 W* N2 ^0 m2 O% h" J
end if;
% b( y' [ j) p U/ Q& h* v) S6 n end process;
' K4 J+ K5 J3 O2 I# H* a clk1<=cnt;
! `- Q8 _0 [: X7 }
. ~2 y. ]7 G9 l' [: U9 q! }8 o, s& w process(clk1)
2 F1 T: K' i6 o begin
! w- s: K: W& x: B# s: n if clk1'event and clk1='1' then
/ U- x0 { H* G if switch='0' then M {0 W! z% z$ \* r; h
count1<=count1 + 1 ;6 C3 p6 Y% m7 d5 ^0 W0 Y1 p0 ?: w
if count1="0110" then |% b0 m# c: u! ~* p! n
count1<="0000" ;
. F) y8 Q9 {% ^/ w$ Z end if;+ |4 ^, D7 ]5 Z! H& j6 V8 O* B
else) E. Y6 v" C+ S! o0 ?0 n( f
count2<=count2 + 1;
3 ^# ]5 s! q8 _3 N# M* ]5 J if count2="1000" then
X- L! {$ A* c4 |, {7 n: ?5 N count2<="0000" ;
4 R& J/ Q! R* Z) s end if;7 _1 u. l: |6 o: P( T
end if;
5 a b5 v( G/ ]( g% X) @8 s/ a end if;
% ?& M- s( e- g" |( \, M) c end process;
' V8 J6 m4 G' q! X. t/ S' J( |後面是我自己要接出去的東西~所以我沒PO!! |
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