MAX7219 8x8 LED matrix with ESP32

Supply 5 V Bus SPI

Pins and ESP32 wiring

Pin	Role	ESP32 pin	Notes
VCC	Power	VIN	Needs 5 V: use VIN
GND	Ground	GND
DIN	SPI MOSI	D23	Data in. 3.3 V signals usually work, a level shifter is safer
CS	SPI chip select	D5	Load (CS)
CLK	SPI clock	D18	Clock

Suggested wiring for the 30-pin ESP32 DevKit, avoiding flash, input-only and strapping pins. BoardPilot checks it for you as you wire.

This module is sold for 5 V. Its outputs may be 5 V: use a level shifter or a voltage divider on ESP32 inputs.

Maxim MAX7219 datasheet, Serial interface DIN, CLK, LOAD (CS); supply 4 to 5.5 V

Part data: CC BY 4.0, free to reuse with credit to BoardPilot.