MAX7219 driver and 8x8 LED matrix display

This library written in Go programming language to output a text messages to 8x8 LED matrix display (pdf reference) via MAX7219 driver chip (pdf reference) from Raspberry PI or counterparts:

Compatibility

Tested on Raspberry PI 1 (model B) and Banana PI (model M1).

Golang usage

func main() {
	// Create new LED matrix with number of cascaded devices is equal to 1
	mtx := max7219.NewMatrix(1)
	// Open SPI device with spibus and spidev parameters equal to 0 and 0.
	// Set LED matrix brightness is equal to 7
	err := mtx.Open(0, 0, 7)
	if err != nil {
		log.Fatal(err)
	}
	defer mtx.Close()
	// Output text message to LED matrix
	mtx.SlideMessage("Hello world!!! Hey Beavis, let's rock!",
		max7219.FontCP437, true, 50*time.Millisecond)
	// Wait 1 sec, then continue output new text
	time.Sleep(1 * time.Second)
	// Output national text (russian in example) to LED matrix
	mtx.SlideMessage("Привет мир!!! Шарик, ты - балбес!!!",
		max7219.FontZXSpectrumRus, true, 50*time.Millisecond)
}

Getting help

GoDoc documentation

Installation

$ go get -u github.com/d2r2/go-max7219

Quick Start

To output a single letter to LED matrix by specifing ascii code use OutputAsciiCode call:

	// Output a sequence of ascii codes in a loop
	font = max7219.FontCP437
	for i := 0; i <= len(font.GetLetterPatterns()); i++ {
		mtx.OutputAsciiCode(0, font, i, true)
		time.Sleep(500 * time.Millisecond)
	}

To output a single national letter either unicode letter (rune) to LED matrix use OutputChar call:

	// Output non-latin national letter (russian for example).
	// You must be sure, that your national letter will match code page of the font used.
	mtx.OutputChar(0, max7219.FontZXSpectrumRus, 'Я', true)

This functionality works not only with Raspberry PI, but with counterparts as well (tested with Raspberry PI and Banana PI). It will works with any Raspberry PI clone, which support Kernel SPI bus, but you should in advance make SPI bus device available in /dev/ list.

More national fonts

If you want to add your national fonts you could use linux shell scripts in folder "extract_fonts" to convert font image to bit patterns. Let me know if you need assistance in this.

Credits

This project is mainly a fork of respective functionality originally written by Richard Hull in python: https://github.com/rm-hull/max7219. Nevertheless it differs in some parts: refuse some functionality (works only with matrix led), include extra functionality (extra fonts, support of national languages).

Contact

Please use Github issue tracker for filing bugs or feature requests.

License

Go-max7219 is licensed under MIT License.