Audio recording and playback of Embedded System base on I2S bus
This paper presents the way of audio recording and playback of Embedded System base on I2S bus,using the LPC2478 microcontroller and UDA1380 Stereo audio coder-decoder.Firstly,discusses the principle of I2S bus,the characteristics of LPC2478 ' s I2S bus interface and UDA1380 Stereo audio coder-decoder.Secondly,elaborates on the design of hardware interface between LPC2478 and UDA1380:audio data is transmitted on I2S bus,and control information is accomplished through L3 bus.Thirdly,explicates the design of software:using the I/O pin simulates L3 bus to initialize the UDA1380 codec,the audio data input and output interfaces of LPC2478 are all initialized to master mode,and connected to GPDMA,explicates the designs of GPDMA drivers to process audio data and diagram flow of audio recording and playback program.