MAX7219 is an integrated serial input / output common-cathode display driver , which connects a microprocessor and an 8 -digit 7- segment digital LED display, and can also be connected to a bar graph display or 64 independent LEDs . It includes an on-chip B -type BCD encoder, multiple scan loops, segment word drivers, and an 8*8 static RAM to store each data. Only one external register is used to set the segment current of each LED .
A convenient four-wire serial interface can be connected to all general-purpose microprocessors. Each data can be addressed without rewriting all the displays when updating. MAX7219 also allows users to select encoding or not encoding for each data.
The entire device includes a 150μA low-power shutdown mode, analog and digital brightness control, a scan limit register allowing users to display 1-8 bits of data, and a detection mode to make all LEDs glow.
It requires only 3 Ge IO ports to drive 1 dot matrix! No flicker during dot matrix display! Support cascading!
Module parameters:
1. A single module can drive an 8*8 common cathode matrix
2. Module working voltage: 5V
3. Module size: length 12.8 cm X width 3.2 cm X height 1.3 cm
4. With 64 fixing screw holes, 3mm diameter
5. Module with input and output interface, support multiple module cascade
Wiring instructions:
1. The left side of the module is the input port, and the right side is the output port.
2. When controlling a single module, you only need to connect the input port to the CPU
3. When the plurality of cascaded modules, the first one input termination module to the CPU , the output end of the two input module, the first two output termination module of 3 input modules, and so forth . ..
Take 51 single chip microcomputer as an example:
VCC → 5V
GND → GND
DIN → P2.2
CS → P2.1
CLK → P2.0