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3#
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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40MHZ8 I. b' y' I Z( P T: W1 k& N
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??
7 @) D" t6 u# q. Z# f9 b+ ]$ Bentity clk_95 is$ ^) w0 i- M9 L4 B& E' A3 g
Port ( clk40 : in STD_LOGIC;
- a& d2 z0 `/ j* J3 ? enable : in STD_LOGIC;
7 ^, }; b/ C$ |% D, ? switch : in STD_LOGIC;, I2 k. G* n) y: v+ x4 D! v
a,b,c,d,e,f,g,p : out STD_LOGIC;
$ s2 L5 J- ]4 a6 h" x SEL : OUT STD_LOGIC_VECTOR (5 DOWNTO 0));+ D8 X5 r* N1 L7 \0 n- W0 M
end clk_95;4 {, N5 A( T# t: t1 A7 ]
9 ^+ E" @" N3 b7 ^, G8 }) [. Earchitecture Behavioral of clk_95 is
; C; b) W) L. ~& y% o- q/ psignal clk1 : STD_LOGIC ;) V. _6 |& k) m
signal cnt : STD_LOGIC ;
( ^9 D, s, ^# m: |0 a) dsignal x1 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);8 }3 C3 g6 d7 G
signal x2 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);
4 [, p. v$ s3 d1 jsignal count1 : STD_LOGIC_VECTOR (3 DOWNTO 0);
( \# K) w: A* h! psignal count2 : STD_LOGIC_VECTOR (3 DOWNTO 0);
% d; x/ m' m, {signal y : STD_LOGIC_VECTOR (7 DOWNTO 0);
& L4 O, U b" B# Gbegin& m4 I: a. @- B, J
$ Y+ x! Y9 ~. e3 a8 {* k' i* A
process(clk40)8 T3 M& A8 t, H" p5 {% w
variable cnt:integer range 0 to 39999999;& k: U6 W8 z) z+ x0 d/ I0 l
begin% ^3 |* V% B2 f9 ^
if clk40'event and clk40='1' then
6 K, a' @2 P0 W$ S3 E, r8 o) r if cnt<20000000 then
6 \- f6 c% W5 @7 r9 O, P# o' Y$ U/ Y cnt:= 0 ;/ V5 R/ m" J1 \6 U6 z% _, q
else
- h Q. Z/ A4 ]. V cnt:= 1 ;+ L6 j" u% E8 ~2 w0 A3 W
end if;
3 ~3 I) D0 f I1 ] end if;
- Q: F' B0 H: g+ N( A& q end process;8 Z4 Z" T3 q& S' Y3 r) c4 A7 f" _8 V
clk1<=cnt;! i z8 H* H$ D1 K( C6 W
5 C. A4 E9 R7 h process(clk1)
: `" s. J a+ n4 K( ^. s7 R7 s3 Y begin9 V! o& E4 z* ^- i
if clk1'event and clk1='1' then4 g3 x W8 ^9 S) W2 s# T/ E8 H. x: @8 _
if switch='0' then. ^0 W7 V3 B8 v8 m) z' {4 I" k8 T0 D
count1<=count1 + 1 ; q' o* \ h1 k0 L3 T7 \) W
if count1="0110" then; ]. B; }0 `, z D+ [, T
count1<="0000" ;
' s, i2 e4 f1 h' c% Z" F- z end if;
% k% _# R* a3 o; n9 l9 I% z else8 P% O0 m% O, i% L' y
count2<=count2 + 1;8 P' ?+ W# Y% {/ |
if count2="1000" then
; |; B5 j. L- ]# Z' _7 U count2<="0000" ;* R6 ]9 j+ _3 o7 v
end if;
" I# G2 o* o" F/ @! |' U I j end if;
9 W+ X) F; U. `& }4 F7 ~$ {( r; ~ end if;
! m+ f3 H3 I0 ~ end process;4 ?7 `5 X0 \! i7 v
後面是我自己要接出去的東西~所以我沒PO!! |
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