TA的每日心情 | 擦汗 2020-1-14 15:59 |
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签到天数: 1 天 [LV.1]初来乍到
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2#

楼主 |
发表于 2008-12-11 20:36
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`timescale 1ns / 1ps0 W- s2 H( D+ L; Z4 y" ]( S
module GreyCounter, N' i9 A7 ~* T4 \
(
" w I+ r1 |# `' A( [$ w d // outputs:/ e5 q4 F0 Y$ Y. p7 t0 e
greycount,
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// inputs:/ _9 i1 H. U6 Q4 c
clk,$ B, U! G; m/ q: y1 O& m
reset_n,
. _- X1 g+ E& ~8 M, I1 R en, `4 D4 }, z, K) Q( q
clr
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parameter WIDTH = 8;
* Y9 T: a: E3 D$ sparameter DLY = 1;! V7 A# ]! C7 P) }
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output [WIDTH-1:0] greycount;
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input clk;
# H$ b% Y& R6 o) E/ Iinput reset_n; z. w% e5 J1 P
input en;2 |" [2 ^9 ?9 W. k( P7 w1 U
input clr;
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reg [WIDTH-1:0] greycount;, f; S [+ {. s) A5 B/ A
reg [WIDTH-1:0] bincount;
5 ?& o3 H0 o& linteger i;
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. s! ]+ x5 ?3 U7 aalways @(posedge clk)% ^* }6 Q" k8 R+ J& D. e5 A
begin7 y9 F, Z- W; A0 M) l7 D
if (~reset_n)- e+ p+ h7 Y8 [6 e% v+ @9 n( _, e
bincount <= #DLY 0;
+ C: J% M! A4 `) ]& {3 r else if (clr)
( g# }! L) N1 }# i3 T( i$ \3 e bincount <= #DLY 0;& L; q: e: X$ {" Q) U- [5 R
else if (en)
9 P/ b5 i" {1 ^: K; C" w/ Q v bincount <= #DLY bincount + 1'b1;
' c& Z0 ~. f" W7 h) J- O+ H else: R6 `; n7 ?/ ^/ [- P1 z( g7 }# q
bincount <= #DLY bincount;
, I, L4 @6 x) Y% B1 v m% Z0 zend
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always @(posedge clk)( {( B, k) D- i. m( n8 l# V
begin
: E+ G, `( a% ~' f. c2 }! P2 ]# L if (~reset_n)/ u- u& e" o1 f4 l0 [, }
greycount <= #DLY 0;0 i# D7 }8 K- b4 b( s% V$ T* Q
else
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greycount[WIDTH-1] <= #DLY bincount[WIDTH-1];& K# c' E- R$ I/ r% p
for (i=WIDTH-2; i>=0; i=i-1)
& C! l- _0 n( R, \ begin- ], b3 {. m: ~- b& a4 B
greycount <= #DLY bincount ^ bincount[i+1];2 x3 p( c: D; T) k: Q
end
0 h# L0 J. a) a) o: s/ `2 ? end
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: T: J! o8 l# ]' u8 Iendmodule
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貌似上面的只能用于激励仿真吧
! s+ ]% _4 u) D3 \for循环 ~~! |
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