Verilog编程实现步进电机的单双八拍的四路脉冲信号。采用28BYJ-48步进电机（驱动ULN2003）验证可以实现其正反转。-Single and double eight four-shot pulse signal Verilog Programming stepper motor. Using 28BYJ-48 stepper motor (driver ULN2003) verification can achieve its inversion.