基于Nios Ⅱ的音频录播系统设计

Design of audio signal recording and playback system based on Nios Ⅱ

为了进一步提高系统对大量高速音频脉冲编码调制(PCM)数据的处理速度,设计了一种使用NiosⅡ软核的新型音频处理方案。该方案采用音频处理芯片TLV320AIC23。NiosⅡ软核通过自定义指令集和Avalon总线与外部数字逻辑协同工作,接收高质量音频信号,并压缩处理回放。其中使用自定义指令集和Avalon总线实现了多采样率可变、旁路监听功能,加速了音频数据的处理和传输,显著提升了系统性能。仿真和调试结果表明该音频录播系统达到了设计指标要求,具有良好的音频录制质量和播放性能。

For further increasing the processing speed of large and high speed audio data in the system, a new type of scheme based on Nios Ⅱ was designed for audio recording, in view of high speed and large quantity and other characteristics of traditional Pulse Code Modulation （PCM） data. The audio processing chip in the scheme is TLV320AIC23. Nios Ⅱ soft- core and external digital logic cooperatively worked by using custom instruction set and Avalon bus to receive, compress and playback high quality signal. Custom instruction set and Avalon bus were used for changing sample rate, bypass monitoring, and accelerating audio prosessing and transmission, thus system performance was greatly improved. Simulation and debugging results show that the audio recording and playback system is up to the design requirements, with high audio quality and playback performance.