Design Of Audio Data Acquisition System Based On ARM And DSP

With the rapid development of embedded technology and multimedia technology, thedigital audio technology has been widely applied. At the same time, people also make higherdemands on digital audio products, the conventional design by using only a single processoris difficult to meet the requirements of the real-time, efficiency, multi-function and otheraspects. Therefore, more and more embedded digital audio system adopt the combination ofARM+DSP to achieve higher performance.Data acquisition and signal processing has become important means of electroacousticmeasurement and audio application. Except some expensive high-end sound cards areprovided with DSP chip, the ordinary sound card or audio data acquisition card, they samplingrate and sampling precision are not high enough, and they aren’t equipped with DSP generally,involve programmable function and digital signal processing rarely. It is difficult to providereliable method and basis for the establishment of sound check、data acquisition andhigh-fidelity sound system. Therefore, it will have great significance to set up a system whichcan realize precision data acquisition and sound processing in scientific research and soundmeasure field.Based on the above background, the research topic of design of audio data acquisitionsystem based on ARM and DSP is put forward by us. Take advantage of the characteristics ofDSP and ARM, play they special advantage fully, DSP takes charge of signal processing,ARM plays Host Controller, take McASP as digital audio interface, HPI is made full use ofto communicate between the dual-core, choose I2S as audio data transmission format,constituting a integrated audio data acquisition system.The main function of the system is to collect sound signal by48kHz\24bit highprecision sampling rate, after ascending frequency interpolation, digital filtering and effectprocessing, through the D/A conversion to real-time playback. At the same time, make use ofHPI to transmit data signal processing results to ARM which upload the acquired data to theupper computer by USB or Ethernet.In the system, task management, interface control and human-computer interaction isbased on ARM. DSP takes charge of fast data operation and processing.We select Samsung S3C2440as ARM, high-performance floating-point chip TMS320C6713which is from TIcompany’s C6000series is choosed as DSP, and AIC23B is used to encode and decode. DSPcommunicate with AIC23B through the McASP interface, and use HPI to exchange data withARM, achieving efficient and real-time transmission of huge amounts of audio data streambetween ARM and DSP.In this paper, the system overall design is provided, have completed the related hardwarecircuit design, including power, clock, reset, AD, DA circuit and HPI interface design,established the hardware platform for audio data acquisition and processing system. Givingthe system software design scheme and flow chart, and introduced the design of softwareinitialization in detail. Realized acquisition and playback of audio data.