说明：  基于arm开发的原理图，可以接显示器、扩展51、触摸键盘等，来源于浙江机电职业技术学院电气系
(Based on the development arm of the schematic diagram, you can then display, the expansion of 51, to touch the keyboard and so on, from the Zhejiang Institute of Electrical and Electrical Department of Vocational and Technical)