GLCD Audio Spectrum Analyzer by Atmel ATmega8

Figure 1 

Here is an audio spectrum analyzer project using an SG12232C GLCD module and based on Atmel ATmega8 microcontroller. The graphic LCD displays both audio waveform in real time and FFT (Fast Fourier Transform) spectrum analysis of the input audio signal.

SG12232C is a 122 × 32 dots full graphics LCD module that has two Epson SID15200 LCD controller on a board. The module requires 2kHz clock singnal which must be applied during power is on, otherwise the static bias may demage the panel. It must be driven by 8-bit interface, there is no 4 bit interface option.

The MAX293 is easy-to-use, 8th-order, lowpass, elliptic, switched-capacitor filter that can be set up with corner frequencies from 0.1Hz to 25kHz. It is used in this audio spectrum analyzer circuit as an anti-alias filter.

The source code and the fixed-point FFT library for ATmega8 are given in the project page. In addition you can find more detailed description about the software and the hardware there.

Read More: elm-chan.org/works/akilcd/report_e.html