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2#
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發表於 2007-11-29 13:32:01
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這是小弟寫的倒數器
`timescale 1ns/1ns+ K8 D% k2 Q; M- h! W2 k" C
module reciprocal_counter_96_11_29 (
; I" [( M& R' @* a- d: f: e; `$ e! G clk,
, J) S0 h+ V- m$ `1 T reset,
+ ~4 j+ d8 f5 x8 d( d min_1,1 t* \; L3 R: G7 n4 h' T* m& W! W% N
min_5,7 S( G9 A, ~+ s3 p
min_10,) o5 ^' ?) o9 A# r" ~( w% \
start,
1 X0 @- ^+ |" C% V% C% l& h reset_ext," l" N) B& R/ {$ h* w
ok( L0 \" G% O' }6 I0 u% q1 o
//外部腳位定義-------------------------------------
* A. o4 V) r0 cinput clk , reset ; //系統 clk reset
: a- L& M. T) ?5 \* ~input min_1 , min_5 , min_10; //設定每按一次1加1按5加一次5按10加一次10/ j+ W0 V; e3 c( s/ D. V; t% E
input start; //開始倒數鍵/ \# `3 G/ K6 F/ r" ~
input reset_ext; //強制歸零並停止倒數
2 C0 m: @2 B9 a. O8 Jinput ok; //用來關掉alarm鬧鈴 4 Y) U2 i% O( _7 P
//宣告內部暫存器---------------------------------------7 i& e3 E/ c% j# b
wire clk , reset , min_1 , min_5 , min_10 , start , reset_ext; //宣告clk , reset , min_1 , min_5
8 ?7 K* D) _3 {; m8 @ // min_10 , start , reset_ext為連接線 j) \- I& ]) |1 y- d$ Q/ K2 y' J
reg [9:0]counter; //宣告counter為暫存器; l- G( F; T7 F. q) K5 t0 @
reg min_1_b; //宣告min_1_b為暫存器+ P# X8 D: B4 {7 _* \) o
reg min_1_bb; //宣告min_1_bb為暫存器( j; O: s) b; V; q) {
wire pulse_1; //宣告pulse_1為連接線
. g- J6 n9 \- v6 Hreg min_5_b; //宣告min_5_b為暫存器
( Q+ r$ u: A7 R7 X2 J6 g# T' u3 Hreg min_5_bb; //宣告min_5_bb為暫存器
( D% S5 K* ^0 H1 lwire pulse_5; //宣告pulse_5為連接線 % [ D; D) B) G! `
reg min_10_b; //宣告min_10_bb為暫存器 % D2 S" Y0 x" C' e
reg min_10_bb; //宣告min_10_bb為暫存器 # _, K4 {: e5 H
wire pulse_10; //宣告pulse_10為連接線 ) M: l* n8 O. t* V% K3 T1 c
reg alarm; //宣告alarm為暫存器
- R9 T; u+ k) M" _: freg ok_b; //關掉alarm鬧鈴的暫存器9 E9 |# T! x' J H5 }4 D3 n
reg ok_bb; //關掉alarm鬧鈴的暫存器% V7 I: |0 a) E. I- P2 H! u
wire pulse_ok; //關掉alarm鬧鈴的訊號# p+ Q8 a( f* M$ P. N! m+ Q! {! @7 [
reg reset_ext_b; //關掉外部歸零的暫存器' \5 y7 l- g6 u. v6 K& p
reg reset_ext_bb; //關掉外部歸零的暫存器# g- F; E# _5 p
wire pulse_reset_ext; //關掉外部歸零的訊號* p6 f- P3 \, i; p# {
reg count_d ; //宣告啟動alarm用9 c- {- G( J- t% T8 F" ]. i
reg count_dd ; //宣告啟動alarm用2 K( u6 X D. c' r! e6 }& _+ D
wire pulse_d ; //宣告啟動alarm用
7 \3 y" y: B4 v5 lreg [7:0]led ;! f; A. F3 G' ]( m
) f5 k% m- a8 u4 _/ {( n; n7 f
assign pulse_1 = min_1_b & ~min_1_bb;2 Q- P0 B; y# \8 v
assign pulse_5 = min_5_b & ~min_5_bb;% J) j! {/ f( t4 F* }
assign pulse_10 = min_10_b & ~min_10_bb;' o& P. Q1 \1 g
assign pulse_d = count_d & ~count_dd ;
6 h& a& i* [8 i; {5 W" ?$ h( }assign pulse_ok = ok_b & ~ok_bb;# F+ t, I! I% ~9 Q6 e% a
assign pulse_reset_ext = reset_ext_b & ~reset_ext_bb;
" r! f5 e) ^! f3 i2 Z8 s/ q: v" F//----------------------------------------------------- g* ?6 Q( m; h8 [) I2 B/ j
//計數跟倒數, a2 ~1 ~$ Q& o4 R+ R2 G6 O; F' b
//-----------------------------------------------------( V5 l% {7 B, P
always @ (posedge clk or negedge reset)
/ K8 ?& ]6 T. a5 m# Xbegin% o2 u$ v; u/ ]; O. \
if(~reset)
/ R$ R7 i) I. a: v& d: l counter <= 0; //把counter 設初始值為零
0 {1 g# L1 b5 ?' x: }& W. u$ H else if(pulse_1) //( M+ g3 @6 s& E" P
counter <= counter + 1; //4 ?/ O6 d# J t- G8 z# U
else if(pulse_5) //設定counter按1 and 5 and 10的累加
4 Y) x: N9 f. ?7 y( g2 c4 G counter <= counter + 5; //
; v/ x' \. m+ V+ d& |" C) D. y* } else if(pulse_10) //" D' |6 Y- S6 R
counter <= counter + 10; //
5 v4 S, X# k0 a5 B7 S else if(counter >0 & start) //設定counter開始倒數
2 A! w8 k+ c" X0 d counter <= counter - 1 ; // 5 \, A- t0 ?' G9 U! a7 q- e
else if(pulse_reset_ext) //設定reset_ext強制關掉所有目前正在執行的動作
2 P9 [0 K& q# i6 b* W% W counter <= 0 ; . y, m0 j; _5 X7 s8 ]: Y8 Y4 g- n
end1 R" |+ F2 O7 l; q
& u, r6 ?/ d' O( Z0 \
$ N/ h3 F/ A/ g+ N7 q' |
. b$ x/ U- M) [$ f7 y+ E) V//------------------------------------------------------7 Q3 ]7 }/ W# N" I+ x5 D" P
//led_counter
7 K) j/ x/ i3 y//------------------------------------------------------ x; }* I* y7 U
, M) U f, Q& c5 m; D
) m5 l/ J! J5 A& ? l5 C+ {
; O# L" | b6 |- l. b7 }- G; n" `0 y5 A
//-------------------------------------------------------7 z* Y1 w" ?4 }; n. k, G2 Y
//alarm鬧鈴5 ?) _/ w" T6 M9 `# q2 ~
//------------------------------------------------------( R/ J" _7 F, J; z
always @ (posedge clk or negedge reset )
- \/ t! p$ V9 jbegin3 l2 I+ C0 x+ `6 N1 G S+ q
if(~reset)
7 D0 S4 F. u F9 I6 D' o, f5 | alarm <= 0 ; //設定alarm鬧鈴初始值為零% N# ]# e, ?0 U% R- f) s* a& T
else if(pulse_ok) //設定當pulse_ok為1時成真,alarm為0關掉鬧鈴
* I1 G+ W0 L' L& M4 ~, N8 Q) \0 u alarm <= 0 ; //, X% n' Q9 a1 V" T/ V
else if(pulse_d) //設定在counter倒數數到零零零時鬧鈴為1聲響起; z5 q; S' F! K2 r) j9 V" q ?2 v
alarm <= 1 ; 5 C! s1 T5 c/ [# G, n8 @; V) o
end
4 y$ A9 }9 ^* P) G8 h# u: Q% h( M//-----------------------------------------------------, _8 }. m1 s/ a; k
//count_d
% m6 K) M1 L; ^9 }1 i O& E' n//----------------------------------------------------/ R8 Y; i# ^+ N2 H3 N: W8 T
always @ (posedge clk or negedge reset) J& j- j3 g. r4 r5 O9 C" P5 ~
begin/ f: P/ ^$ P v" q8 D/ C( v
if(~reset)8 I! Y9 R9 e" E6 o4 D
count_d <= 0;' | d! V6 L* G2 \+ ^2 h+ Y
else if(start & counter == 2)
3 X5 d# P0 i9 z# B) I- R count_d <= 1 ;
9 R9 Y$ K9 {# R9 V9 ^// else if(pulse_reset_ext)
* J" E. z. S4 P3 N else
9 a; j, d- \( ?1 ?4 w) H# e& d1 H* D9 p count_d <= 0;3 h/ B+ M [0 N2 w
9 @4 ]0 f* M! J m3 f: v
% n) u# x3 j. X- Y( j9 y( g
2 R' ^ y- y2 T, B% z, ^end
) ?0 _( c% Y1 k* u; d//--------------------------------------------------------------
& B. o9 r8 M1 `- C0 b//count_dd
+ O6 x* K8 ? e5 D! @2 O//--------------------------------------------------------------6 d6 b0 `2 j, Q, V$ V8 N: l
always @ (posedge clk or negedge reset) # }# A. n: s2 c/ B& a! u4 q. n) h
begin
3 w& K/ ]/ E# D. |8 J! W4 r if(~reset)
' u# x% E. K/ v6 ~ count_dd <= 0 ;
$ W# \, f( n( M8 n; |3 n* Z3 i else if (start & counter == 1)* }, T3 C( {9 U& A& S: o+ K A" W5 R
count_dd <= count_d ;
8 Q1 W, s! ~4 r7 K8 p2 S+ W// else if(pulse_reset_ext)6 H2 Z; t8 f0 Y& w6 Q+ C
else
& i1 u+ J4 u8 J9 E7 l ?, G. a count_dd <= 0; 0 T0 ]$ B3 C, G( h% j* c
3 D: b, l3 x; E4 X' [' mend
! A5 W- ?8 d& C
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