brand new and high quality Feature: The MAX7219 is an integrated serial input / output co-cathode display driver that connects a microprocessor with an 8-digit 7-segment digital LED display or a bar graph display or 64 independent LEDs. Which includes an on-chip B-type BCD encoder, multi-scan circuit, segment word drive, but also a 8 * 8 static RAM used to store each data. Only one external register is used to set the segment current for each LED. A convenient four-wire serial interface can be connected to all common microprocessors. Each data can be addressed at the for time of updating without having to rewrite all the displays. The MAX7219 also allows the user to select or not code for each data. The entire device contains a 150A low power shutdown mode, analog and digital brightness control, a scan limit register allows the user to display 1-8 bits of data, and a test mode for all LEDs to emit light. Only need 3 IO port can drive a dot for matrix! Dot for matrix display without flicker! Support cascade! Module parameters: 1. A single module can drive an 8 * 8 coin lattice 2. Module operating voltage: 5V 3. Module size: Length 12.8 for cm X Width 3.2 for cm X Height 1.3 cm 4. With 64 fixed screw holes, aperture 3mm 5. Module with input and output interfaces, support multiple modules cascade. 6. Light Color: Blue/Green/Red 7. Quantity: 1 Pc Wiring Instructions: 1. The left side of the module to the input port, the right to an output port. 2. When the control of a single module, simply input port connected to CPU. 3. When a plurality of cascaded modules, input and output termination CPU, an input terminal of the second output end of the first module a module, the first two modules of the input terminal of the three termination modules, and so on. Take 51 MCU as an example: VCC 5V GND GND DIN P2.2 CS P2.1 CLK P2.0 Note: No retail package. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Includes: 1 x MAX7219 Module