为下列代码添加注释：ADC0809 module ADC0809(D,CLK,EOC,RST,ALE,START,OE,ADDA,ADDB,ADDC,Q,LOCK_T,CLK_OUT); input [7:0]D; input CLK,RST; input EOC; output reg CLK_OUT; output ALE; output START,OE; output ADDA,ADDB,ADDC,LOCK_T; output [7:0]Q; reg ALE,START,OE; parameter s0=0,s1=1,s2=2,s3=3,s4=4; reg[4:0]cs,ns; reg[7:0]REGL; reg[5:0]CLKIn; reg LOCK; always @(posedge CLK) if (CLKIn>10) begin CLK_OUT=~CLK_OUT; CLKIn=0; end else CLKIn=CLKIn+1; always @(cs or EOC)begin case(cs) s0:begin ALE=0; START=0;OE=0; LOCK=0; ns <=s1;end s1:begin ALE=1; START=1;OE=0; LOCK=0; ns <=s2;end s2:begin ALE=0; START=0 ;OE=0; LOCK=0; if(EOC==1'b1)ns =s3; else ns =s2;end s3:begin ALE=0; START=0; OE=1;LOCK=0; ns =s4;end s4:begin ALE=0; START=0 ;OE=1;LOCK=1; ns <=s0; end default :begin ALE=0; START=0 ;OE=0;LOCK=0; ns =s0; end endcase end always@(posedge CLK or negedge RST) begin if(!RST)cs<=s0; else cs <=ns;end always @(posedge LOCK) if (LOCK)REGL <=D; assign ADDA=0; assign ADDB=0; assign ADDC=0; assign Q=REGL; assign LOCK_T=LOCK; endmodule

// 这是一个ADC0809模块
module ADC0809(D,CLK,EOC,RST,ALE,START,OE,ADDA,ADDB,ADDC,Q,LOCK_T,CLK_OUT);

// 输入信号
input [7:0]D;
input CLK,RST;
input EOC;

// 输出信号
output reg CLK_OUT;
output ALE;
output START,OE;
output ADDA,ADDB,ADDC,LOCK_T;
output [7:0]Q;

// 定义寄存器和参数
reg ALE,START,OE;
parameter s0=0,s1=1,s2=2,s3=3,s4=4;
reg[4:0]cs,ns;
reg[7:0]REGL;
reg[5:0]CLKIn;
reg LOCK;

// 时钟输出
always @(posedge CLK)
if (CLKIn>10)
begin
CLK_OUT=~CLK_OUT;
CLKIn=0;
end
else
CLKIn=CLKIn+1;

// 状态转移
always @(cs or EOC)
begin
case(cs)
s0:begin
ALE=0;
START=0;
OE=0;
LOCK=0;
ns <=s1;
end
s1:begin
ALE=1;
START=1;
OE=0;
LOCK=0;
ns <=s2;
end
s2:begin
ALE=0;
START=0;
OE=0;
LOCK=0;
if(EOC==1'b1)
ns =s3;
else
ns =s2;
end
s3:begin
ALE=0;
START=0;
OE=1;
LOCK=0;
ns =s4;
end
s4:begin
ALE=0;
START=0;
OE=1;
LOCK=1;
ns <=s0;
end
default :begin
ALE=0;
START=0;
OE=0;
LOCK=0;
ns =s0;
end
endcase
end

// 状态机
always@(posedge CLK or negedge RST)
begin
if(!RST)
cs<=s0;
else
cs <=ns;
end

// 寄存器
always @(posedge LOCK)
if (LOCK)
REGL <=D;

// 输出信号
assign ADDA=0;
assign ADDB=0;
assign ADDC=0;
assign Q=REGL;
assign LOCK_T=LOCK;

endmodule