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本帖最后由 chenqinte 于 2009-5-5 14:34 编辑
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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
$ M) h9 u5 i% k; c- hlibrary ieee;# o: |! f# p) @& j/ M- l' D
use ieee.std_logic_1164.all;
`) ^: c/ i* u3 ruse ieee.std_logic_arith.all;5 G% s0 E8 B, s8 T0 ~9 N* o
use ieee.std_logic_unsigned.all;! j3 ~0 ?% Q# S L0 \
entity febpin is
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clk:in std_logic;
! L. ~( b) |# F- k- o- ~ div3:inout std_logic" C9 X; M1 U% {) ]
);
! F' g8 |) t% _* u w2 Dend;6 R5 W" Y- e( ], ]# j4 R" d' K
architecture behavioral of febpin is
# y' h9 C* t5 d2 `$ G) isignal cnt:integer range 0 to 2;8 [3 t, X5 T6 j1 o4 e
signal q:std_logic:='0';
2 r. Z' s6 V. g _begin; d* i' m8 O' _
process(clk)
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if (clk'event) then. N5 Z0 \# y' j
if cnt=2 then. G& z; o3 A5 V: J3 \' p+ m
q<=not q;3 {0 x. ~. K- w1 [' U
cnt<=0;
% q' z! O: I2 F else
l% q( m. M6 a# C4 h% c) U+ u cnt<=cnt+1;" D0 f5 P/ o0 W! ]5 _
end if;* V- [0 P' v" W6 D' x2 p
end if;
0 w. j- Y, {& z) r end process;' c1 p; ? I/ W6 P
div3<=q;
4 p/ j3 m9 c3 ?, Zend behavioral; |
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