SainSmart MAX7219 Red LED Dot Matrix Display Module MCU Control DIY Kit for Arduino;

Module parameters:

1.A single module can drive an 8 * 8 common cathode lattice
2.Module Operating voltage: 5V.
3.Module size: 5 cm long X 3.2 cm wide X 1.5 cm high
4.With four screws hole, aperture 3mm, by using our M3 Tongzhu fixed
5.Module with input and output interfaces, supports multiple modules cascade

Wiring instructions:

1.The module left as an input port to the output port on the right.
2.The control of a single module, simply input port to the CPU
3.Multiple modules cascade input termination CPU, 2 output termination module, a module of the input of the input terminal, the output terminal of the first two modules of the first three modules, and so on ...

51 MCU, for example:
VCC †' 5V
GND †' GND
DIN †' P22
CS †' P21
CLK †' P20