The netduino GO! Piezo Buzzer module has a single piezo buzzer. The buzzers tone is set using the call SetFrequency.
Here is a quick video Christoc
made to show what can be done with it and how:
NetduinoGo.Potentiometer pot = new NetduinoGo.Potentiometer();
NetduinoGo.PiezoBuzzer buzzer = new NetduinoGo.PiezoBuzzer();
buzzer.SetFrequency(pot.GetValue() * 2000);
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