There are two methods.

Method # 1

1. Hold down the "Code" key.
2. While holding the "Code" key down, press the key corresponding to the number.

Method # 2

1. Press the "Num" key to enter the "Number Lock" mode.

   The "Num" indicator (the triangle) in the bottom left corner of the display comes on.

2. Press the key corresponding to the number.
3. Press the 'Num" key again to exit the "Number Lock" mode.