基于Quartus的抢答器的设计，用VHDL硬件电路设计实现的模拟电路，用FPGA开发板可看到效果，一共八个按钮，有复位键-Quartus Responder based design using VHDL hardware circuit design and implementation of analog circuits, FPGA development board can see the results, a total of eight buttons, with reset bu