|
本帖最后由 chenqinte 于 2009-5-5 14:34 编辑
9 c' M# B- t- k) F' n" B, M
5 Z6 m; g+ L7 ]* v: R. K没人顶哦,这是我写的一个小程序不过仿真的结果可以实现3分频,但在板子上跑时,分频乱七八糟的,不知道为什么
" J2 k8 u- F- n! vlibrary ieee;5 w6 [5 V. N) |( g) Y+ ?+ F
use ieee.std_logic_1164.all;0 w0 o J! q: N6 p) D3 }* m
use ieee.std_logic_arith.all;
$ L: z7 i; }4 r2 X. |use ieee.std_logic_unsigned.all;
, E0 f- d3 H% Sentity febpin is9 g4 {. f9 _0 F& V$ Q% w. j5 T
port(2 U& B8 M: b5 P; s+ z6 {5 x
clk:in std_logic;
6 w+ K0 _2 v ]8 D div3:inout std_logic4 N5 v4 M1 w1 j; F+ M+ B0 ~
);, s% t2 m t( `; e$ q
end;
6 T; E* N4 j0 i, e* S) ~architecture behavioral of febpin is4 r# V4 n J" j
signal cnt:integer range 0 to 2;
7 n: R( u4 e- z. V3 k1 @3 asignal q:std_logic:='0';4 |5 C4 r% |* l
begin
3 y) `0 r" G) S4 z! J: ` process(clk)
" K* ^ P: ^1 B6 w% y% d8 u# r9 M begin. M" e2 q+ E/ ~+ [' k
if (clk'event) then
9 e5 @' ]2 ~' Q# l2 P! i- X if cnt=2 then' q; D) s" l' e: J* Q4 |) P% l
q<=not q;
: i3 \/ \3 {/ @5 N cnt<=0;; b6 @; X4 c5 v9 K4 Q) D
else
4 B6 p% S) e. H: Z7 N' W* G$ I cnt<=cnt+1;
/ y* ^' a0 y o end if;
l: w6 L# {; w* n- Q6 @ end if;
. Y( d' }7 S' ?, Y: l end process;
$ ^& S) Y- `8 Z0 { div3<=q;8 F1 B; n/ H6 b
end behavioral; |
|