Intellectual Converter from RS-232 to RS-485/RS-422 Interface
[Abstract] With the wide application of the computer in industry, a good many current control systems have much more difficulty in satisfying the need of controlling equipment to adopt the control method of the unit. Because of the situation, RS-485 interface chip has extensively already applied in industrial control, instrument, network of multimedia and integrated product of electro mechanics, etc. At present, there are a lot of solvable plans of changing level between RS-232 and RS-485/RS-422, for example the adapting method. But the majority of the plans have less common ability, take up too many systematic resources, the hardware and software of them are too complicated, and the cost of them is too high.
[Key words] RS-232，RS-485/422，Interface，Intellectual converter
目录
标题摘要……………………………………………………………………6
总体设计……………………………………………………………………7
1.1 功能描述…………………………………………………………………7
1.2 结构框图…………………………………………………………………7
1.3 工作原理…………………………………………………………………8
硬件设计……………………………………………………………………9
2.1 DC-DC转换电路…………………………………………………………9
2.2 RS-232接口…………………………………………………………… 10
2.3 RS-485/RS-422接口……………………………………………………12
2.4 微处理器…………………………………………………………………15
软件设计………………………………………………………………24
附录……………………………………………………………………30
