十秒钟步进电机轮流反转并显示在数码管上，单双八拍工作方式：A-AB-B-BC-C-CD-D-DA (即一个脉冲,转 3.75 度)-10 seconds of stepping motor rotation reversed and displayed on the digital control, single and double eight work: A-AB-B-BC-C-CD-D-DA (ie a pulse, turn 3.75 degrees)