说明：  周立功 485 用户指导手册，很强大。有详细电路图，不用找型号上面很清楚。 老外写的485通讯例子.485_guide.pdf RS485协议.pdf 485通讯.rar RS232转RS485电路图.doc RS485协议 485总线常识.pdf 485总线应用与选型指南.pdf 看完后基本不用找别的了。
(ZLG 485 user guide, very powerful. A detailed circuit diagram, do not look for models above is clear. Written by 485 foreigners example .485 _guide.pdf RS485 protocol. Pdf 485 communications. Rar RS232 to RS485 circuit. Doc RS485 protocol 485 common sense. Pdf 485 bus application and selection guide. Pdf After reading the basic need to find anything else.)