基于CPLD的曼彻斯特码高速传输系统设计

DESIGN OF A HIGH RATE MANCHESTER'S CODE TRANSMITTING SYSTEM BASED ON COMPLICATED PROGRAMMABLE LOGICAL DEVICES

介绍了一种基于复杂可编程逻辑器件 (CPLD)的曼彻斯特码高速数据传输系统设计方案。其特点是 :①将曼彻斯特编码、解码及其相关的控制逻辑集成于CPLD中 ,减小了传输系统的规模 ;②工作方式由微处理器 (MPU)编程控制 ,可以根据传输信道的特性选择不同的数据格式及传输速率 ,通用性强 ;③输入、输出采用并行方式与先进先出缓冲存储器接口 ,传输过程中无须干预 ,降低了传输系统对MPU的负载 ,有利于系统总体性能的提高。该方案特别适用于实时多任务下的高速数据采集与传输系统。

Based on complicated programmable logical devices (CPLD), a high-rate data transmission system of Manchester's code was realized. In this system, Manchester's encoder, decoder as well as relative timing and control logic are integrated into CPLD chips, which greatly minimizes the scale of transmission system. Data format and transmitting rate can be programmed by microprocessor unit (MPU) according to the characteristics of transmission channels, which makes the system very universal. The Manchester's encoder-decoder parallel interfaced with first-in-first-out memory (FIFO) makes transmitting procedure run automatically as data transfers between encoder-decoder and FIFO can be done without MPU, which greatly decreases MPU's burden and improves specifications of the applied system. It especially adapts to real-time, multitasking data acquisition and transmission system at high speed.