This is an evaluation use of a small graphics LCD module. Last summer, SG12232C graphic LCD module has been sold sold for 1500 Yens from Akizuki Denshi and I bought it. However I could not find good application for the LCD module and it was going to go to junk box :-) so that I tried to use the LCD module temporary. Only displaying any still image is not cool, first I tried to display an audio wave form in real-time like a digital oscilloscope, and then an FFT spectrum analysis too. The spectrum monitor seems to achived nice performance, in view of it is realized with a cheap microcontroller.