To make the Arduino work with NTK, you need to upload the Standard Firmata sketch to the firmware.
Instructions
1 Install Standard Firmata
To communicate with NTK, the Arduino must have the Standard Firmata sketch installed on it.
- Download the Arduino IDE
- Depending on the platform (mac, pc or linux) and which Arduino board you have, you may need to install drivers as outlined on the official Arduino Getting Started page
- Plug the Arduino into your computer with a USB cable.
- Install Standard Firmata
- Open the Arduino IDE software  and select File>Examples>Firmata>StandardFirmata
- Select the correct board from Tools>Board
- Select the correct serial port from Tools>Serial Port (e.g. mac: usbmodemxxx pc: COMxxx)
- Upload Standard Firmata to your Arduino by clicking on the right arrow button in the upper left of the sketch
For more detailed instructions on getting your Arduino working, see the following: