To build the electronic circuit you need the following parts:
- a piezo element,
- a 1kΩ resistor,
- and a couple of wires.
The schematic for the circuit looks like this:
...and the circuit on your breadboard should look something like this:
If everything is set up right, you can connect the board to the serial (or USB) port of your computer and, if necessary, to the power supply. The power LED should light up and the next step is to export the programm which reads the state of the switch to the board. Open the ap_ReadPiezoKnock.pde file in Arduino, set the right serial port and baudrate, compile the programm, and then press the reset button on your board and click on the export icon to send the program to the board.
To check if everything works fine so far, see if the control LED lights up when the switch is on ON-position. Now, you can download and unzip pa_PiezoKnock.zip and open the file pa_PiezoKnock.pde in Processing. You will have to set the right serial port, which you do by editing the variable portname. Eventually you will also have set the correct baudrate by editing the variable baudrate.
Now, you can run your Processing programm. A new window will open and you should see something like this:
If you...