作出原理图，在这里要用到原理库，作用就是把你用到的那个元器件在sheet上表达出来，protel里面有自带的原理图库，但是有可能你需要的一些新器件找不到，这时候就需要你自己建一个原理图库了2，原理图做好以后就可以生成网络表格，这个东西就是原理图和你最终要做的PCB的连接的桥梁，还可以生成所用器件列表等等(Make the principle diagram, use principle library here, the effect is that the components you use to express in sheet, PROTEL inside the gallery with principle but there may be some new devices, you need to find it, you need to build a library of 2 principle, principle diagram to do a good job after you can generate a web form, that is the principle chart and you'll end up doing PCB bridge connection, can also generate the device list and so on)