For questions about the interface between the user and the firmware using a 128 x 64 LCD display and a rotary dial button.

The RepRapDiscount Full Graphic Smart Controller is a full graphic Smart Controller for the 3D printer containing an SD-Card reader, a rotary encoder and a 128 x 64 dot matrix LCD display (and a reset button and a beeper). You can easy connect it to your printer board using two 10 pins connectors for flat ribbon cables.