• Is it possible that it's actually to do with wiring? Do you have GND properly connected between the controller and the MAX7219?

    Or how long are the wires you're using? An 8x8 LED matrix at 5v can draw a lot of power, so with long, thin wires the voltage drop can be enough that you get communications issues.

    You can easily change the baud rate if needed though: http://www.espruino.com/Reference#l_SPI_­setup


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