用verlog实现8253的模式控制

/************************************************************************
FMEw2WYN0?207219*************************************************************************EDA中国门户网站Bp#z1\tq+mw~K
*************************************************************************EDA中国门户网站([i0WwR3YMHh
********     design project:   channel 0 of 8253 timer           ********
M(E6D5^Kal N207219********        designer   :                                     ********
efdAs7O5_!i#w207219********        company    :sounthern yangtze university         ********
/U#Wyk/`P H8J207219********           date    :   April 15th in 2007                ********
0s#I-h/S*q ?207219******** detail information:                                     ********
P^*x\dh207219********           this module is the RTL description            ********
2pI4s
O:vnt207219********           of  8253 timer, it includes six operate       ********
P3C[zDwP+_'Xp207219********           models ;the table following is the            ********
q4G iS^x5Q
d+Q B?207219********           control words of channel 0 of 8253 timer:     ********
&pg|9K&]+Em4L207219********                         model0: 10H,11H,                ********EDA中国门户网站yC4mI)@+b4L{YW-V
********                         model1: 12H,13H,                ********EDA中国门户网站[F(IK#}t
********                         model2: 14H,15H,                ********EDA中国门户网站_|/i|k'jG$_G
********                         model3: 16H,17H,                ********EDA中国门户网站d.|"Q6I7Y
********                         model4: 18H,19H,                ********EDA中国门户网站?*Z&~7tT%e/v
********                         model5: 1AH,1BH,                ********
0imY"oh.b8cNc.H:M207219*************************************************************************EDA中国门户网站bc{7} U
*************************************************************************
BD%R^@)a6R207219*************************************************************************
,y2d4f6t"w
oh` x\n207219************************************************************************/
]wUcV#k2xN
iN207219//
zV~W[ W9}207219module TIME(out,                  // output  of counter 0;
\/s Ya
cd207219       state_rd,                  // state of reading;
$P$X(x[p@G*C207219              d,                  // date of input;EDA中国门户网站 l:mAXt0s1Y} K)T
          d_out,                  // output of cuttently value;EDA中国门户网站S9W8[wEr%D w
           gate,                  // control signal of gate ;EDA中国门户网站W$Ge V3g!u5CybU7v
           n_cs,                  // select signal;EDA中国门户网站WXj:f3r qW4sa&M
           n_rd,                  // read   signal;EDA中国门户网站d ?#xPfA0b
           n_wr,                  // write  signal;EDA中国门户网站`,g6G;yz]#sH!` Lk
             a1,                  EDA中国门户网站*On9~\&I_i$P
             a0,
9^0W'S'D;ki7MtI207219            clk);                 // clock  signal;
+Y;dy;xA207219          //  rst);EDA中国门户网站AY+I O
W+{
//

output  [7:0] d_out;EDA中国门户网站3v`)A/lX
output  out; EDA中国门户网站R0~Ae*UR*u
output  state_rd;
1lOU \`*L'E y4@t M V207219//

input  gate,clk;
ju0W.?J/E207219input  n_cs,n_wr,n_rd;
KJ9c9G1H8u-i207219input  a1,a0; EDA中国门户网站DY(|3_ M${oET
input  [7:0]  d;EDA中国门户网站
a$|7Cd t ?2[HM1O1W
//

reg    [7:0]  control;            // reg of control word;
b0x4@4sd3I_-|207219reg    [15:0] cnt,cnt1,cnt_a,cnt_b,cnt_c;
vPE(y*Z0x207219reg           out_a;EDA中国门户网站%doI7ptQ0C)C
reg           out_b;EDA中国门户网站y0W`\_t
reg           start_f;            // flag of startup;EDA中国门户网站2P{.T(Vv~i ~vy
reg           state_wr;           // state machine of writing;
9f'V2C.JY)^*JRPL+B207219reg           state_rd;           // state machine of reading;

ML?'UH)qh207219reg     [1:0] cnt_f;EDA中国门户网站/] ~fPi
reg           nta,fla,flb,flc,fld,sta;// some internal control signal;
B\1f0I7M'J3G207219//

wire    [7:0] d_out;EDA中国门户网站6n$K!} h4ytC2m7[
wire    nw_r;
VNBaB%qR207219wire    ntb;EDA中国门户网站v*q0^
] Oo6i
wire    out;
m$yu
r`t6r"d-N/Mn207219wire    clock;
L2}1D)cs9FT|4o A207219wire    clock1;

//EDA中国门户网站`k9KCP4k
assign  out=out_a && out_b;
\#th+rs8{(` ep:E!@207219assign  ntb=~start_f;EDA中国门户网站FQu(I[G;_*T&I
assign  clock= clk && start_f &&  gate;
d?
M2^/u1W`m207219assign  clock1=clk && start_f &&(!gate) ;

t]
Dh[
l"`fDl0K207219//

always@(posedge gate or posedge ntb )
8S@^P7P-S6qM207219if(ntb==1)begin sta<=0;flc<=0;end
F6t E~/Z;W-o207219else begin sta<=1;flc<=flc+1'h1;end

//
%Q#oG8E/\Ib8^207219always@(posedge n_wr or  posedge ntb)EDA中国门户网站I#^e$`.@e ]8kN
if(ntb==1) begin nta<=0;fla<=0;endEDA中国门户网站xf(|Y,k9_+L9Ab
else begin nta<=1;fla<=fla+1'h1;end

//EDA中国门户网站A*`L l-^h(F AoN
o$o
always@(negedge  n_wr )EDA中国门户网站/}#^:XCD'TX8CD
case (state_wr)EDA中国门户网站+f-MrS6W]
1'b0 : if  (n_cs==0 && a0==1 && a1==1 &&  EDA中国门户网站.ko!W3ZT YBc!n;]
           n_rd==1 && d[7:6]==2'b00 && EDA中国门户网站$PSZJpGK
           d[5:4]!==2'b00)EDA中国门户网站'R!C;C5o [&E
         begin
Coa O/]_207219           control<= d;start_f<= 0;state_wr<=1'b0;EDA中国门户网站*jy$W7p5N7s*uQ
         endEDA中国门户网站"M4^[E G1KYV
       else if(n_cs==0 && a0==1 && a1==1 &&
i]TEeN!|y(n+L207219               n_rd==1 && d[7:6]==2'b00 &&
.r!P|8r2ht&BN207219               d[5:4] ==2'b00)   
IV'SE2p$B-v$A4im207219          beginEDA中国门户网站,p7hX
v[BZ
            state_wr<=1'b0; cnt_c<=cnt1;EDA中国门户网站
G1K+L`;a-Cr.W FcHq*J
          end
2Y U&{G Myn,_7s207219       else if(n_cs==0 && a0==0 && a1==0 &&EDA中国门户网站6tt;u*\-q
               n_rd==1 && control[7:4]==4'b0011)EDA中国门户网站.EL-P#U'd)q*w+b o
              beginEDA中国门户网站 Y(~ hH y!_.lg:k
                  state_wr<=1'b1; cnt_b[7:0]<=d;EDA中国门户网站 ZrU^s)t&H$o
              end
@-_:{,S'Z207219       else if(n_cs==0 && a0==0 && a1==0 EDA中国门户网站XEuetq
               && n_rd==1 && control[7:4]==4'b0001)
V4Wsk8?!qx&`207219              begin EDA中国门户网站Y,n/i*O|F_-~
                  state_wr<=1'b0; start_f<=1;cnt_b[7:0]<=d;EDA中国门户网站d'dT Xb
              end
-m
Nb*}$X Gt207219        else if (n_cs==0 && a0==0 && a1==0EDA中国门户网站2\#A+Y
yYf:@J c^Y
                 && n_rd==1 && control [7:4]==4'b0010)
X/K v+Y _Mc*V207219              begin EDA中国门户网站6UE\Z!oTD6j jn
                 state_wr<=1'b0; start_f<=1; cnt_b[15:8] <=d;EDA中国门户网站'Z{
rX_3dj`_
              end
,ySF,AJ207219//EDA中国门户网站~ta|!B@
1'b1:     if(n_cs==0 && a0==0 && a1==0 &&EDA中国门户网站H})W'_CST}v
                   n_rd==1 && control[7:4]==4'b0011)
n+U0Dv.v Y%Q207219              begin
Ew(Y$@2fG%IY207219                   state_wr<=1'b0;cnt_b[15:8]<=d;start_f<=1;
o\9I6O'}l207219              end
K Yn,A[_{B$Y(yA207219//EDA中国门户网站y"uSHm QB9\6Y
default : state_wr<=1'b0;
%JJ FF.|U.lK207219endcase
cGa jsb207219//

always @(negedge n_rd)//posedge nwe
$H.LnSR~]207219case(state_rd)
TU C2{5oRtV|2072191'b0:if( n_cs==0 && a0==0 && a1==0 && n_wr==1)
l4_4\!|&_p5t]4g207219      state_rd<=1'h1;EDA中国门户网站7~5n:oyOO G
1'b1:if( n_cs==0 && a0==0 && a1==0 && n_wr==1)EDA中国门户网站8n~U9H:l|ptA8T&z
        state_rd<=0;  EDA中国门户网站'j.yU5J@0V OL.K:U
default: state_rd<=0;

O)n"W-ln$O8}u;k207219endcase

//
1T6C/[hYI6m207219assign  d_out=(n_rd==0 && n_cs==0 &&  a0==0 && a1==0 && state_rd==1)?cnt_c[7:0]:8'bzzzzzzzz;
:pb|#G:W2xP&H"j[.m207219assign  d_out=(n_rd==0 && n_cs==0 &&  a0==0 && a1==0 && state_rd==0)?cnt_c[15:8]:8'bzzzzzzzz; EDA中国门户网站:W_Y
[iV
//

always@( negedge clock or negedge start_f)// or negedge gate)EDA中国门户网站,K+F-\oW~(D
if(start_f==0)EDA中国门户网站:kZtFrh G
begin
tv
UB^-o)N207219out_a<=1;
`"}$z&HU$z t207219cnt<=0;EDA中国门户网站/C,cX4v0l/l
flb<=0;EDA中国门户网站7k+cm Ge/yX
cnt_f<=0;
pns+j,k207219end
lJ7`F9Ba.Xg207219else
FG ZBu:? R-Y207219case(control[3:0])EDA中国门户网站"x,][K"t
m5d]u}
4'b0000:// mode0 //binary counterEDA中国门户网站h)Q#nP6]*[
s9ctGe
       if(start_f==1&&nta==1)EDA中国门户网站3v%Cy;O.kcg)|
             begin  if(fla!==flb)
B;g6O/|tL207219                        begin cnt<=cnt_b; out_a<=0; flb<=fla; end
%vR5GDn3vG207219                    else if(cnt==1)EDA中国门户网站x;~Sb*Uc!zz^
                        begin out_a<=1;cnt<=cnt-16'h1;end
!mu-[OsT&FSx9G C207219                    else if(cnt==0)EDA中国门户网站'p3@lg3wB4H\]*E
                        begin out_a<=1;cnt<=0;endEDA中国门户网站 Rg&[3i5E{1U
                    else cnt<=cnt-16'd1;
IF\j8rt+X207219              end
uy-v|e*CJ3d6X207219//
p8{,w0S3m2072194'b0001:// mode0 //decimal counter
/ZZ[#H4D](t8k207219       if(start_f==1&&nta==1)
&B3?0g WP+TT*CH8v207219              begin  if(fla!==flb)EDA中国门户网站B8`*D)Y#y#dS
                          begin cnt<=cnt_b; out_a<=0;flb<=fla; end
p,F1Wy3eLdBL-}207219                      else if(cnt==1||cnt==0)EDA中国门户网站9WZ7`8QY#K l o
                          begin   out_a<=1;cnt<=0;end
W6i6N6E+hf hY207219                      else count_decm(cnt);
"j*d K*t.I1`J"gB|207219               end 
!OrB&P)@ajX:@8r207219//
)o1Ih5WnLB2072194'b0100://mode2 //binary counter
vc4FT\207219        if(start_f==1)
KF mJS,Y7~207219               begin  if(cnt_f==0)
r.p$Ol.E f8d I207219                            begin  cnt<=cnt_b;cnt_f<=1;out_a<=1;end
g5J%lG4GKX7x7b207219                      else  begin if(cnt==2&&cnt_f==1)EDA中国门户网站v:l!P'S6D \0zZ
                                    begin out_a<=0;cnt<=cnt-16'd1;cnt_f<=0;endEDA中国门户网站l A`A;|5H4^
                                  else cnt<=cnt-16'd1;EDA中国门户网站8xR2bkj f
                            end                           

B"Q%xvcu{x207219               end
j6P
{
flyd9M,do207219//
1Y!K VMlwy,\'~*S2072194'b0101: //mode2//decimalcounter 
A*q(HZtE207219         if(start_f==1)
{+\^UO q3Miwc
~S&i207219                begin  if(cnt_f==0)EDA中国门户网站(b1og2L)X { ^2s
                            begin  cnt<=cnt_b;cnt_f<=1;out_a<=1;endEDA中国门户网站4N;lQo`2x s+E
                       else begin if(cnt==2&&cnt_f==1)
Wh'~0p
cePr207219                                    begin  out_a<=0;count_decm(cnt);cnt_f<=0;endEDA中国门户网站B+cp#Hr
                                  else count_decm(cnt);
#wx/a+y1E!f207219                             endEDA中国门户网站p!{5@t;x
b+c k
                end
w0l#H%AvJx*Vk8G7JL_`207219//EDA中国门户网站0wq"DY ]5S-a
4'b1000://mode4//binary counterEDA中国门户网站^Pzc0N P
          if(start_f==1&&nta==1)
R j e8]'Cc-a/X207219                 begin   if(fla!==flb)EDA中国门户网站0}S$Z]|jn*B~SB
                            begin  cnt<=cnt_b;out_a<=1; flb<=fla;end                                       
D ZhKw"?J5]207219                         else  begin  if(cnt==1)
7E f$y/E8R U*m207219                                        begin   out_a<=0;cnt<=0;flb<=~fla;end
h[ vi:n
[207219                                      else  cnt<=cnt-16'd1; 
^XSw/Z4\p207219                               end                   EDA中国门户网站!~ z9e,MLs Vj j0e
                 endEDA中国门户网站ES!Bn5@dL
 //  EDA中国门户网站mj7Kl*uxa
4'b1001: //mode4 // decimal counter    
D xL0V6Gq207219         if(start_f==1&&nta==1)
J;?#HSp,RM207219                  begin   if(fla!==flb)EDA中国门户网站fzxYGE
                              begin  cnt<=cnt_b; flb<=fla;out_a<=1;end  EDA中国门户网站O L`VW!H
                          else  begin if(cnt==1)EDA中国门户网站5j.i df)X
                                          begin   out_a<=0;cnt<=0;flb<=~fla;endEDA中国门户网站\} df)ic2b)mEc \mEB
                                      else  count_decm(cnt);  EDA中国门户网站X7u8ZC^k
                                end                  
mw4~x!@V8W!O207219                  end            EDA中国门户网站5p/q!v OM"Xa
//EDA中国门户网站3V&{M'yWT O
4'b0110: //mode3// binary counterEDA中国门户网站Mwcae8yt
         if(start_f==1)EDA中国门户网站;cX7BC+bTr&v
Mu'u-o
                  begin  if(cnt_f==0)
1bSH[O H7S+R207219                              begin cnt<=cnt_b;cnt_f<=1;out_a<=1;end                             EDA中国门户网站1bc(yTb2I i&y!QS
                          else if(cnt_f==1&&gate==1)EDA中国门户网站+Y4D5d#TX:n6X)P
                              begin cnt_a<=(cnt_b>>1)+16'd1;EDA中国门户网站7T8G_vgb{
                                    if(cnt==cnt_a) EDA中国门户网站O$j{pzQ
                                       begin out_a<=0;cnt<=cnt-16'd1;endEDA中国门户网站%p}j'Zuj9B
                                    else if(cnt==1)       EDA中国门户网站U$r](~{+Y?
                                      begin out_a<=1;cnt<=cnt_b;endEDA中国门户网站N~_w@H_
                                    else  cnt<=cnt-16'd1;
$~@6}q6@(~;OW207219                               end
:bL@ ~]Q&d:F X p207219                           else  if(out_a==0 && gate==0 && cnt_f==1)EDA中国门户网站@7[6q F5`7Q)e
                                  begin cnt_f<=0;end  EDA中国门户网站#g-c|;^fdh
                    endEDA中国门户网站 c,Lcl_Wu rxF
//
IM;a1W QD` ^2072194'b0111:  //mode3 // decimal counterEDA中国门户网站+gqNH'emO
        if(start_f==1)
7HA] O`M|207219                   begin  if(cnt_f==0)
#KD:{*V4v(w+w3f2A*`-H207219                              begin cnt<=cnt_b;cnt_f<=1;out_a<=1;end
)l?6I1`w _#W'ap} z207219                           else
+v$CC1rA4~207219                              begin   suan;    EDA中国门户网站"y2s8t\0IK)O
                                      if(cnt==cnt_a+16'h1) EDA中国门户网站o+v'j/q }8X
                                          begin out_a<=0;count_decm(cnt); endEDA中国门户网站~+zUnN&~_
                                      else if(cnt==1)  begin out_a<=1;cnt<=cnt_b;end
;s4FzA(`y207219                                      else count_decm(cnt);
kq,[ _^)Zc$Y*yH207219                              endEDA中国门户网站7UICxsl0T#_
                    endEDA中国门户网站p[M-pBkk
//EDA中国门户网站
Y`cB"o s
default :cnt<=0;EDA中国门户网站J&^;Z+ruH
endcase
lP%a8f i"XXD4e207219//EDA中国门户网站1`A&a0G%bf\5ON.E
always@(negedge start_f or negedge clock1)EDA中国门户网站&`|Gs,V!L
`
if(start_f==0)EDA中国门户网站l/xc/N[!@q^
begin out_b<=1;fld<=0;end
%k9m\
`"}*~-K'x?207219else case(control[3:0])
9JY/r8C2mg2072194'b0010://mode1//binary counterEDA中国门户网站2RMI:wJ
         if(start_f==1&&sta==1)
)Z#OQ.KG3r]207219              begin
C*]IWX$T207219                 if(fld!==flc)
W+q+x\waj%Q207219                       begin  cnt1<=cnt_b;out_b<=0;fld<=flc;end 
C5q4{1uu4Uw!\C)Q207219                  else if(cnt1==1)EDA中国门户网站nxP ?1@]5G$H
                       begin out_b<=1;cnt1<=cnt1-16'h1;fld<=~flc;endEDA中国门户网站$N8roY9C%e V y\K9Mv
                  else if(cnt1==0) cnt1<=cnt_b;
&l`,n"w!p,]KW207219                  else    cnt1<=cnt1-16'h1;EDA中国门户网站6d5Hl*c b
              end EDA中国门户网站rGU7Wg7x8[ u9r
//
*]:N9X9^)I9}U/g2072194'b0011: //model1//decimal counterEDA中国门户网站^~,Et$e@N
          if(start_f==1&&sta==1)EDA中国门户网站^$jyh&q|1[
              beginEDA中国门户网站&R&Wfxkp|q*YD
                 if(fld!==flc)EDA中国门户网站%cfq8P6q4lV
                       begin  cnt1<=cnt_b;out_b<=0;fld<=flc;end  EDA中国门户网站\X ^N5yk&yIT
                 else if(cnt1==1)EDA中国门户网站;}7ls~%ThL1r&Y
                       begin out_b<=1;count_decm(cnt1);fld<=~flc;end
pu.sdpq207219                 else if(cnt1==0) cnt1<=cnt_b;
{_ CA/n207219                 else    count_decm(cnt1);
'kEGz,pAI207219               end
MC-S&jFQ207219//
oL7SzDY2072194'b1010: //mode5//binary counterEDA中国门户网站,{.dQR;Q7f1i;F
          if(start_f==1&&sta==1)
-fS:Wh!sM N207219               beginEDA中国门户网站6v-N0?2u'P*MFv
                  if(fld!==flc)
+h Tb-M8]-Ed
kE8]207219                       begin  cnt1<=cnt_b;out_b<=1;fld<=flc;end  EDA中国门户网站9|n,xG1R2n4p
                  else if(cnt1==1)EDA中国门户网站0D8S;f s!c+KK's2B
                       begin out_b<=0;cnt1<=0;fld<=~flc;end                             EDA中国门户网站,xPh)ecTF f-z
                  else    cnt1<=cnt1-16'h1;
5pr3~uB U207219               end
\!k0wT*^207219//
cD0X{'q_2072194'b1011://mode5//decimal counterEDA中国门户网站L&I"[KDg
         if(start_f==1&&sta==1)EDA中国门户网站aSxH U\p
               beginEDA中国门户网站cC,prLcL%A/}"wr"~
                  if(fld!==flc)EDA中国门户网站k8L!Z@L'T*?J5e K
                       begin  cnt1<=cnt_b;out_b<=1;fld<=flc;end  EDA中国门户网站Ax2x2?7`
                  else if(cnt1==1)
Yvf*t%vwf207219                       begin out_b<=0;cnt1<=0;fld<=~flc;endEDA中国门户网站Np/yG]m"x
                  else   count_decm(cnt1);EDA中国门户网站{2GG%X1IoK$kV
                endEDA中国门户网站m;_Q1}8k5Z0t
default :cnt1<=0;
b1N+m[{e~ \3q207219endcase
9H&t,JA7t,r4p_207219//
F:WZ'ffa!~ED207219// task of decimal counterEDA中国门户网站C#N#R Q/_
task  count_decm;
U#sF&i\8r@207219inout [15:0] cnt;EDA中国门户网站_U?8wL'I
beginEDA中国门户网站9qkc*N-KwB1kY
  if(!cnt[3:0])begin cnt[3:0]<=9;
9y~]"xW}n!K207219                     cnt[7:4]<=cnt[7:4]-4'h1;
J#Ki!UC,W5hV#]_Z207219                     if(!cnt[7:0]) 
t!vb ?&WOz,|t/N#S207219                         begin cnt[7:0]<=8'h99;EDA中国门户网站QWm|]k
                              if(!cnt[11:8]) 
&y'bnx%rI
i207219                                 begin cnt[11:8]<=9;EDA中国门户网站r:^%HM n[:np ?
                                       cnt[15:12]<=cnt[15:12]-4'h1;
dP?"m1ZxI3g207219                                       if(!cnt[15:8])EDA中国门户网站!w+e vZ!g;|c*ey4B
                                       begin cnt[15:8]<=8'h99; endEDA中国门户网站U zI@7N;T
\
                                  endEDA中国门户网站D7C.V5\;O)D5C/L,L
                               else cnt[11:8]<=cnt[11:8]-4'h1;   
1m]
FB$u#?Pkc3N E207219                          endEDA中国门户网站b1l[;K} w8VZ
                end
)NB|A%Ed207219else   cnt[3:0]<=cnt[3:0]-4'h1;EDA中国门户网站GI/Z(XB)F N2_$jl
end
|2dp3FJPND207219endtask  
l;@0e/]t8[.\&Z207219//EDA中国门户网站 UY@.ep\YqI8O
task suan;EDA中国门户网站 ps+rn"y Ec
if(cnt_b[12]==0)EDA中国门户网站L pvxOq
 begin if(cnt_b[8]==0)
X+`)_0[H'nf:n(H,N$L207219              begin if(cnt_b[4]==1)                    
g-LKM#u~u r2@
]%m207219                         cnt_a<=((cnt_b>>1)-16'h0003);                         EDA中国门户网站 VP w(V:q.S
                    else cnt_a<=(cnt_b>>1);EDA中国门户网站4o/[S6|,~@ @(`*A*s[M
              endEDA中国门户网站8h d
Y%K ~xbo
        else 
*n9z(k2^'c-|P207219              begin if(cnt_b[4]==1)
;Sw.P%VF207219                       cnt_a<=((cnt_b>>1)-16'h0033);EDA中国门户网站;U^Kg
Gk w0s(v
                    else
8U/_[|.nyVbvII207219                        cnt_a<=((cnt_b>>1)-16'h0030);
9\ i,Upr6?P$JR207219               endEDA中国门户网站dK'p shzr~
end EDA中国门户网站j{7]v0b/gG&^)C
else
%l
GE+s.H9p207219begin if(cnt_b[8]==0)EDA中国门户网站g8N3ym.x3J3O,@
         begin if(cnt_b[4]==1)EDA中国门户网站(}lJ
s)CP[
               cnt_a<=((cnt_b>>1)-16'h0303);
Jfd b9azhg207219               else cnt_a<=((cnt_b>>1)-16'h0300);EDA中国门户网站J;]N'G-lG
         end
Y[0x_}@O0y207219      else
'} c6j7N5t {hlLH8F207219         begin if(cnt_b[4]==1) EDA中国门户网站gM:|7Z{Ck9hKJ]H5f
                cnt_a<=(cnt_b>>1)-16'h0333;
/jCc8P&A!@3Q6@207219               else
h3D5Pv:i!B$Z;_207219                cnt_a<=(cnt_b>>1)-16'h0330;
iz9g+gK(b {?U"B$Et207219         endEDA中国门户网站}|:uo]S
endEDA中国门户网站el,i&i;e
endtaskEDA中国门户网站0e{(I_,W
endmodule