Display Modules - TOOGOO(R) 4 in 1 Dot Matrix MCU LED Display Modules DIY Set for Arduino 5 PC connection cable Red There is a built-in serial input / output common cathode display driver. Can be connected to the miniprocessor and 7-segment digital LED display von eight digits. Also can be connected to the bar graph or 64 independent LED. Includes Type B BCD encoder, multiple scanning circuit and segment driver. A static RAM (8 * 8) is used to store data.