3Pcs MAX7219 Dot Matrix Module MCU LED Control Module Kit ForSpecifications:A single module can drive an 8 x 8 common cathode latticeOperating voltage: 5VSize: 5 x 3.2 x 1.5 cm (L x W x H)LED color: RedWith four screws hole, aperture 3mmWith input and output interfaces, supports multiple modules cascadeWiring instructions:1. The module left side as an input port and the output port on the right2. To control a single module, just connect the input port to the CPU3. When cascading multiple modules, the input port of the first module connect to the CPU, the output port connect to the input port of the second one, and so on.In the case of 51 MCU:VCC5VGNDGNDDINP22CSP21CLKP20Note:1. VCC and GND is not reversed, it would burn the chip!2. When the 51 microcontroller P0 port controlling, must be connected to the pull-up resistor, it is recommended that the resistance of 4.7K--10K3. Please install lattice into the round hole first, and then insert the round hole to PCB board and weld. Face the side of lattice with words, from left to right pin order is 123456. PCB board 1st pin is square pad!4. Electrolytic capacitors long-pin as positive, short-pin as negative; ceramic capacitor hsa no positive and negative pointsPackage included:3 x LED module3 x Dupont line (5P-20cm)