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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, Y- y( B7 P9 a+ q- e/ o
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??1 t0 X3 v; r4 h7 [: n
entity clk_95 is
& G' U- C, C: w6 W4 r3 I0 S# o! ~% H Port ( clk40 : in STD_LOGIC;5 Q- b* B: P; N% u6 D0 q1 P1 [
enable : in STD_LOGIC;0 W( ^2 r( g2 C0 \& X0 E
switch : in STD_LOGIC;" h z& h% h0 k
a,b,c,d,e,f,g,p : out STD_LOGIC;
; T3 z6 m% c4 g/ ?* A0 H4 f SEL : OUT STD_LOGIC_VECTOR (5 DOWNTO 0));" z J" X0 [" O
end clk_95;# i7 G! z" c( q4 `: [8 o0 g
# c( g! w3 G. e7 M/ Tarchitecture Behavioral of clk_95 is
0 h: C4 p( n' ^- F8 t5 C- psignal clk1 : STD_LOGIC ;
/ ]4 r8 P3 n1 h6 isignal cnt : STD_LOGIC ;% F) L9 R `! n4 f9 c h d
signal x1 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);1 ^1 t2 u- g$ b( G6 w3 K g% n
signal x2 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);
! L- K& w/ U) v1 G, L9 k( Vsignal count1 : STD_LOGIC_VECTOR (3 DOWNTO 0);
; {& m1 Y! S2 f- i; f7 Xsignal count2 : STD_LOGIC_VECTOR (3 DOWNTO 0);$ q2 Q( x4 j3 ~( n2 X) s3 \& i
signal y : STD_LOGIC_VECTOR (7 DOWNTO 0);
+ ^5 k5 ` k- f9 b# b4 Ebegin; Q4 }+ m4 \) }3 C+ \+ l/ ?
' h8 L3 n# C7 \4 n& |/ X
process(clk40)
]' K, J! k! Y( C1 E variable cnt:integer range 0 to 39999999;
- x9 {$ a8 `" a% {$ d" Q8 E begin
/ d+ Q9 S {- P* `: ?7 [7 [ if clk40'event and clk40='1' then
% e& ^- V# z7 S- R0 z if cnt<20000000 then$ b9 l) r. I& |$ h' u
cnt:= 0 ;
7 J6 A( t% e i7 d k/ l else * t) G$ Z. j" D) f4 \
cnt:= 1 ;
1 \) \6 O8 h* ] V+ ]) D. u& v end if;
" Y l' _% p( m5 g end if;
4 w, X c. b1 E7 V) k end process;/ n! R) Y$ L! @% F2 I8 a& t9 s- R
clk1<=cnt;0 ^4 g% F6 I& i9 o$ D
* n6 V5 a2 K9 f; M' L3 W \
process(clk1)
" h- }' ]$ D6 r( e+ _ begin
: x) Y7 k ~3 w if clk1'event and clk1='1' then
, k$ ]& T, i$ k9 T+ e, O if switch='0' then
- j- b! I1 k6 W2 t count1<=count1 + 1 ;. M$ F( U- h |
if count1="0110" then3 b S+ O, F' ]
count1<="0000" ;
2 A u- u$ }% |8 m3 O V end if;
7 T& G! j* w" E0 H. p; K; b( | else* x# g0 y- n0 u# s7 r
count2<=count2 + 1;
) p* X! {, |6 }: K if count2="1000" then* _3 R q8 w. E- V ~
count2<="0000" ;
, k+ y( F; h. K' A end if;1 N$ c3 e7 a9 ~/ f3 |( c
end if;
& A3 Z7 d, ~9 K* L" Y4 H$ Q/ y end if;8 S/ n5 b, F$ s1 K- O! h. z3 p
end process;8 G, c9 O, g$ T8 @* |' Y! i Y
後面是我自己要接出去的東西~所以我沒PO!! |
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