A NodeMCU library to write to MAX7219 8x8 matrix displays using SPI
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README.md

NodeMCU MAX7219

License

A NodeMCU library to write to MAX7219 8x8 matrix displays using SPI

http://frightanic.com/iot/max7219-library-nodemcu-making/

max7219 = require("max7219")
max7219.setup({debug = true, numberOfModules = 4, slaveSelectPin = 8})
max7219.write({
    { 0x20, 0x74, 0x54, 0x54, 0x3C, 0x78, 0x40, 0x00 },
    { 0x41, 0x7F, 0x3F, 0x48, 0x48, 0x78, 0x30, 0x00 },
    { 0x38, 0x7C, 0x44, 0x44, 0x6C, 0x28, 0x00, 0x00 },
    { 0x30, 0x78, 0x48, 0x49, 0x3F, 0x7F, 0x40, 0x00 }
  }, { rotate = "left" })

All missing features are tracked as issues on GitHub.