自适应波特率的DL/T-645规约通信的实现

Implement of DL/T-645 Protocol Based on Adaptive Baud

介绍在电力系统计量类设备中应用广泛的DL/T-645通信规约。提出根据起始符比特流的特征,运用位传输时间相对比值确定帧起始符,并自动判断传输波特率的自适应通信方法,给出基于PIC18F452的捕获功能模块(CCP)和通用串行口(UART)的光电隔离的RS485自适应通信接口电路,指出硬件设计的关键问题和软件设计要点,并给出自适应波特率计算以及帧接收流程图,提供实用的设计参考。

The DL/T-645 protocol used in equipment for measurement of power is introduced. A method of calculating self-adapted baud and acknowledgement of start byte is put forward, which uses relative ratio of bit transmission time, according to bit flow of start byte of frame. A self-adapted communication interface of RS485 bus basing on electricphoto isolated UART and capture module, and the keys of hardware and software are provided. The flows of self-adapted baud and receiving frame and the applicable reference for implementation are brought up.