我才开始自学plc，问题太菜的话请师傅们包容一下！
用cpm1a控制步进驱动器，写了如图的梯形图，不知能否运行，有些确实搞不懂，比如bcd码怎样表示等等，问题在以下图中，麻烦解答，O(∩_∩)O谢谢！

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