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<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform -n ;;;no output ;-iadc ;;;uncomment -iadc if realtime audio input is needed too ; For Non-realtime ouput leave only the line below: ; -o serialRead.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ; sr = 44100 ; ksmps = 500 ; the default krate can be too fast for the arduino to handle ; nchnls = 2 0dbfs = 1 instr 1 iPort serialBegin "/dev/cu.usbmodemfa131", 9600 ;connect to the arduino with baudrate = 9600 kGain init 16 ;read our knob value kVal serialRead iPort if (kVal != -1) then kGain = kVal/128 endif aSig in ;get our audio input and get its rms kRms rms aSig*kGain kRms = kRms*kRms*255 ;scale the rms to a good value for the LED and send it out serialWrite iPort, (kRms < 255 ? kRms : 255) ;must be in range: 0-255 endin </CsInstruments> <CsScore> f 1 0 1024 10 1 1 1 1 1 1 i 1 0 200 e </CsScore> </CsoundSynthesizer>