byte outputPin = D4;
void setup() {
// put your setup code here, to run once:
Serial.begin(115200);
}

void loop() {
// put your main code here, to run repeatedly:
//todo: make a blacklist of misbehaving frequecies
long newFreq = random( 9, 20 );
long newDuration = random( 2048 );
long newDutyCycle = random( 6, 6 + PWMRANGE / 2 ) ;

analogWrite( outputPin, newDutyCycle );
analogWriteFreq( newFreq );
Serial.println( "duty: " + (String)newDutyCycle + " freq: " + (String)newFreq );
delay( newDuration );
}