PDA和PC服务器间远程串行通信协议的设计与实现

The Design and Realization of Remote Serial Communication Between PDA and PC

1.导言 近几年来,个人数字助理(PDA)由于其价格低、携带方便、操作简单等优点,应用领域越来越广.PDA在农业信息化和医疗保健等方面的应用给人们带来极的方便,因而很受欢迎,易于推广.例如,在农业信息化方面,目前的农业专家系统基本上是基于PC平台上的,不便于带到田间地头直接指导农业生产,另一方面,我国大部分农村还不富裕,PC机的价格还难以承受,影响推广的范围.因此,就我国目前的状况,农村迫切需要便携式、系列化(包括低成本)的农业专家系统.

In this paper,a communication protocol based on RS-232 asynchronous serial communication port and connection established by modem dialing, which is suitable for data transmission between PDA and PC,is designed not only to realize remote serial communication between PDA and PC,but also to construct the base for PDA's future use of accessing information from the Internet. A kind of self-adaptive flux-control strategy is presented in this protocol to adapt the different running speed between PDA and PC. The protocol is easy to implement, and is of high communication efficiency and reliability, and can be widely adopted in other serial communications established by point to point connection.