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3#
樓主 |
發表於 2008-5-18 17:13:16
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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: p4 x+ g2 l- ]% ]( v. M1 P; P4 [
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??: Q% u) c0 W' B7 i& I1 R- J' K
entity clk_95 is
- M; J4 J# d# ^2 \ Port ( clk40 : in STD_LOGIC;
4 u8 G& i4 L4 F( ]# V enable : in STD_LOGIC;; _* h$ ]0 W7 H
switch : in STD_LOGIC;
+ [: J4 D7 _( d% `1 \ a,b,c,d,e,f,g,p : out STD_LOGIC;
2 [4 e5 {3 N Y6 ~# Y SEL : OUT STD_LOGIC_VECTOR (5 DOWNTO 0));& _1 g6 Y( }1 ^* R
end clk_95;
8 W( R. Q( r2 u; {- R g5 b2 P4 G" N0 O8 b$ K
architecture Behavioral of clk_95 is1 C# s/ u: C$ T0 u2 h( Y/ r, s
signal clk1 : STD_LOGIC ;# u) \+ e1 n8 x9 r* Y9 t
signal cnt : STD_LOGIC ;7 X/ t$ d+ B: k1 c; _- K
signal x1 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);! _$ z& O; A9 k" v% Q2 x
signal x2 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);" c6 ?6 a. ]( m- I8 O( Z' w( Y
signal count1 : STD_LOGIC_VECTOR (3 DOWNTO 0);: u% ]) z+ Y; R7 y" c
signal count2 : STD_LOGIC_VECTOR (3 DOWNTO 0);
* s# D! u: z- ~signal y : STD_LOGIC_VECTOR (7 DOWNTO 0);" n# z* M5 T! u/ l- g, ?2 H
begin( U. Y1 r" v2 z( \- w+ M9 }
" E! k" N+ l# w+ l
process(clk40)
. v5 h2 _4 [7 E% s' q# \, s$ | variable cnt:integer range 0 to 39999999;
& V; h. G; W. P( ~ begin0 M% t' e" g! M# S4 r9 c
if clk40'event and clk40='1' then( W% F/ v& n8 `0 G3 F5 u
if cnt<20000000 then4 J7 k2 Z' P8 ~: `# Z
cnt:= 0 ;
; q q5 h/ h/ ~ T( Z% M5 Q else
. I) M B' K5 b9 y, Q cnt:= 1 ;
' I6 b$ n% i* _2 {6 K end if;7 K9 p; |0 P3 m
end if;- @2 E D: R0 {& W+ F) ^' @! `
end process;4 G$ U( i) [' H3 A! S
clk1<=cnt;- s+ n3 L0 s% W) f9 o( W
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process(clk1)* A" h, n8 \. M4 n. h; N% q
begin9 f( z9 H& ?# ?' a0 i6 i, a( X* _
if clk1'event and clk1='1' then) j4 w0 N! b/ [% T
if switch='0' then: b/ z0 Z2 g+ M+ e" M( M$ y
count1<=count1 + 1 ; T/ t* O2 A: g1 o# b- r' U
if count1="0110" then- H5 k, W0 t$ {, ~3 ^/ g
count1<="0000" ;* F" W3 D( ]4 H+ h; y: V" Z
end if;' S8 G7 x+ c) V& [
else
( K8 H3 R5 H* @ count2<=count2 + 1;5 I W5 n0 j \( K
if count2="1000" then3 `2 S7 `2 d. p4 H+ x- h$ c
count2<="0000" ;, K3 Z: S* n7 z+ I9 Q5 w
end if;
1 h4 Y+ ?( T, @ end if; 9 l$ k7 M+ `3 [0 }
end if;
8 g W: h, ^! h end process;
% q7 _2 b7 f) t$ N後面是我自己要接出去的東西~所以我沒PO!! |
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