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This library is for the MAX7219 ONLY.
The original version is for esp8266, I modified a little to adapt it for esp32.
Just clone the code and copy it to your Arduino/libraries folder
Demo 5: How to use Arduino ESP32 to display information on SPI LED matrix http://www.iotsharing.com/2017/05/how-to-use-arduino-esp32-to-display-spi-led-matrix.html