
module top;
wire x_in1,x_in2,x_in3,x_in4;
wire y_out;
system_clock #200 clock1(x_in1);
system_clock #150 clock2(x_in2);
system_clock #100 clock1(x_in3);
system_clock #50 clock2(x_in4);
A01_4_Unit AH1(y_out,x_in1,x_in2,x_in3,x_in4);
endmodulemodule
A01_4_Unit (y_out,x_in1,x_in2,x_in3,x_in4);
input x_in1,x_in2,x_in3,x_in4;
output y_out;
wire y1,y2;
and #1(y1,x_in1,x_in2);
and #1(y2,x_in3,x_in4);
nor #1(y_out,y1,y2);
endmodulemodule
system_clock(clk);
parameter PERIOD = 100;
output clk;reg clk;
initialclk = 0;
always
begin
#(PERIOD/4) clk = ~clk;
#(PERIOD/4) clk = ~clk;
#(PERIOD/4) clk = ~clk;
#(PERIOD/4) clk = ~clk;
end
always@(posedge clk)
if($time > 1000) #(PERIOD-1)$stop;
endmodule