원문정보
초록
영어
A novel device which can play audio files with LED lights whose RGB effects are based on frequency spectrum analysis to the audio signal while it is playing is introduced in this paper. Not only can the device bring us with songs, but also it presents colorful lights while we appreciate music. RGB light mixed principle and the relations between music and light colors which are through LED lights driven by PWM are investigated. The device is composed of SD card, U disk to store medium files, the audio decoder to produce audio signals, speakers etc., and the all components are under the control of a microprocessor. The proper sampling rate is chosen for frequency analysis, and the Fast Fourier Transform (FFT) method is optimized to suite for the application. File system is implanted to the microprocessor system which possesses wireless communication Xbee, whose functions such as medium file selection can be controlled remotely.
목차
1. Introduction
2. System Design
3. Algorithm of Frequency Spectrum Analysis
3.1. Reverse order analysis
3.2. Butterfly computing algorithm
4. Software Modules Analysis
4.1. SD card operation via znFAT
4.2. VS1003 operation
5. Conclusions
Acknowledgements
References