Matrix Display Interface with MAX7219
The MAX7219 LED driver saves microcontroller pins and processing time. It uses only three IO pins of an Arduino. It is easy to connect multiple displays by connecting DIN and DOUT pins.
Using a single MAX7219 you can drive 64 LEDs while you only need 4 wires to interface it to a microcontroller. In addition you can daisy chain multiple MAX7219 chips for bigger displays. Continue reading Moving message display using arduino