基于CPLD的多波形信号发生器设计

Design Based on the CPLD Multi-wave Signal Generator

鉴于教学实验的需要,采用Max+PlusⅡ开发平台,VHDL编程实现,基于可编程逻辑器件CPLD设计多波形信号发生器。整个系统除晶体振荡器和A/D转换外,全部集成在一片EPM7256SRC208 15芯片上。他可输出频率、幅度可调的正弦波、三角波、方波、任意波形和两种波形线性组合的10种波形。任意波形模块可由用户自行编辑所需波形数据,经下载在不改变整个系统硬件连接的情况下,输出用户所需的特殊波形,实现了传统的函数信号发生器不具有的一些波形的产生,满足了教学实验和开发新的实验项目对特殊波形的要求。整个设计采用VHDL编程实现,其设计过程简单,极易修改,可移植性强。另外由于CPLD具有可编程重置特性,因而可以方便地更换波形数据,且简单易行,为教学带来极大方便。

In view of the demand of teaching experiment,the multi-wave signal generator is designed based on programmable logical component CPLD,the VHDL programming realization and the Max＋Plus Ⅱ development platform. Besides the crystal oscillator and the A/D transformation,the entire system completely integrates on the EPM7256SRC208-15 chip which is produced by Altera Corporation of USA. The multi-wave signal generator may output the sine-wave,the triangle-wave, the square-wave,the free profile and two kinds of profiles linear combination, totally 10 kinds of profiles which the frequency, the scope can be adjusted. The free profile module may voluntarily be edited by the profile data based on the user＇s needs, then downloaded under the situation which the entire system hardware connects do not change,and finally output the special profile which user needs. The multi-wave signal generator generates wave which the conventional function signal generators can＇t make. It satisfies the demand to the special wave in the teaching experiment and the new projects. The whole design realizes by the VHDL programme. Its design process has simple feature,easy modification and high transportation, Moreover because of the programmable reset feature of the CPLD, the generator can change the wave data conveniently and practice easily,so it brings enormous convenient for the teaching.