Design Of Digital Audio Delay Based On OMAP Plantform

To improve the defects of the current methods, a digital audio delay system based on Texas Instruments's Open Multimedia Application Platform (OMAP) was proposed. The software architecture is based on OMAP's software technical. By using Embedded Linux and DSP/BIOS RTOS to deal with system control task and audio signal process task, the system meet with the demands of application in the new generation Digital Audio Delay.The design of the hardware was introduced, including the OMAP3530 applications processor's special architecture and the audio data pretreatment module which is based on IIS serial bus interface standard.The software architecture which is based on Embedded Linux General Operating system and the DSP/BIOS Real Time system was illustrated, specially analysing the communication mechanism between the two Operating system. Then the software architecture which is mainly based on Embedded Linux Operating system was illustrated, and the mechanism of audio device driver is fully discussed, so is the realiation of Char Device Driver. The realiation of the applications is based on multithreading mechanism, which is also fully discussed in this paper.The algorithm of Automatic Gain Control in frequency domain and the algorithm of digital filtering in frequency domain are fully presented, so their realiation on the TMS320C64x+ DSP Core by using DSP/BIOS Link.Test results show that this design with high delay precision and high audio quality also have good performances in system stability, scalability, and portability.