module top( clk, button , led);
input clk,button;
output led;
reg led;
always @(posedge clk)   //当clk上升沿时触发
begin
led<=~button;
end
endmodule
用时序仿真 是可以仿真的 用的是QUARSII 自带的仿真波形那个 没用modelsim     可是点击功能仿真则出现错误：   Error: Run Generate Functional Simulation Netlist (quartus_map top --generate_functional_sim_netlist) to generate functional simulation netlist for top level entity "top" before running the Simulator (quartus_sim)   谢谢大虾啦 此帖出自小平头技术问答