今天做出來的波形

程式碼：

module top;

wire a,b;

reg c;

system_clock #100 clock1(a);

system_clock #50 clock2(b);

always#1 c=a&b;endmodule
module system_clock(clk);

parameter PERIOD=100;

output clk;

reg clk;

initialclk=0;

alwaysbegin#(PERIOD/2)clk=~clk;

#(PERIOD-PERIOD/2)clk=~clk;

endalways@(posedge clk)

if ($time>1000)#(PERIOD-1)$stop;

endmodule