atmega88驱动步进电机，K3,K4按键控制加速和减速，K1,K2控制开关和正反转，并在5110液晶上显示（还显示进度条）-atmega88 drive stepper motor, K3, K4 buttons control acceleration and deceleration, K1, K2 control switch and rotating, and in the 5110 liquid crystal display (also displays a progress b