MAX7219 is an integrated serial input / output common-cathode display drivers, which connects the microprocessor 7-segment digital LED display with 8 digits, you can also connect a bar graph displays or 64 independent LED. On which includes a B-type BCD encoder chip, multi-channel scanning loop, segment the word drive, but also an 8 * 8 static RAM for storing each data. Only one external register is used to set the segment current of each LED.
Display is 0.36″ 4 digit led display 7 seg segment Common cathode Red
Material: PCB + Electronic Components
Size: 82 * 15 * 18mm
Wiring instructions (for example, it can connect any IO port, modified the Port Definition in the program):
VCC → 5V
GND → GND
DIN → P00
CS → P01
CLK → P02
VCC and GND do not reversed, it would burn the chip
51 MCU P0 port requires pull-up resistor, if your device does not have a pull-up resistor can be connected to other ports data lines.
1 8-Digit Digital Tube Display Control Module