大容量音频实时录放系统的设计研究

Design of large capacity real-time audio recording system

为满足大容量实时录放音频需求,同时保证音质和信息完整性,设计了基于DSP、音频编解码芯片、存储介质SD卡的大容量音频实时录放系统软硬件方案。通过通用IO口模拟SPI协议实现了无集成SPI接口环境下的SD卡实时读写,解决了系统的大容量问题。重点在详细测试分析单缓冲录放方案的基础上,提出采用乒乓缓冲和定时中断技术解决音频录放实时性问题。实际测试表明,由该方案形成的系统录放音质良好,实时性高,能够满足大容量存储应用需求。

In order to satisfy the demand of high capacity recording and playing of audio in real time while ensuring the tone quality and information integrity,a scheme is presented for hardware and software of a large capacity realtime audio recording system based on digital signal processing（ DSP）,audio codec chip,and storage medium SD card. In order to solve the problem of large capacity system,the general IO port is used to simulate SPI protocol to achieve writing and reading through SD card in real-time under non-integrated SPI environment. The emphasis of this paper is to solve the real-time problem of audio recording and playing by the Ping-Pong buffer and timer interrupt technology,on the basis of testing and analyzing single buffer recording and playing scheme. The actual test shows that the sound quality recorded by this scheme is good with high real-time performance,thereby meeting the application requirement of large capacity storage.