简单的十计数器VERIlog程序看看有什么问题

mzcry

module count10(cin,clk,cout,qout);
input cin,clk;
output [3:0] qout;
output cout;
reg [3:0]qout;
always @(posedge clk)
begin
if(cin)
begin
if(qout[3:0]==9) qout[3:0]=0;
else qout[3:0]=qout[3:0]+1;
end
end
assign cout=((qout[3:0]==9)&cin)?1:0;
endmodule

计数测试进位 加一