stepper motor control through computer parallel port with winxp realized by vc 下并口步进电机控制
as crystallization progresses across the temperature gradient, it is possible to move the sample by precise stepper motor control ( at specified rate ) in the opposite direction so that the crystallization front remains in the field of view 当沿着温度梯度方向发生结晶过程的时候,可以向相反方向通过高精度步进马达移动样品,这样可以把结晶前沿始终保持在视域中。