README.md

MicroPython MAX7219 8x8 LED Matrix

A MicroPython library for the MAX7219 8x8 LED matrix driver, SPI interface, supports cascading and uses framebuf

PyBoard Examples

Single 8x8 LED Matrix

import max7219
from machine import Pin, SPI
spi = SPI(1)
display = max7219.Matrix8x8(spi, Pin('X5'), 1)
display.text('1',0,0,1)
display.show()

Chain of 4x 8x8 LED Matrices Where the 4 is drawn on the DIN matrix.

import max7219
from machine import Pin, SPI
spi = SPI(1)
display = max7219.Matrix8x8(spi, Pin('X5'), 4)
display.text('1234',0,0,1)
display.show()

Chain of 8x 8x8 LED Matrices Where the 8 is drawn on the DIN matrix

import max7219
from machine import Pin, SPI
spi = SPI(1)
display = max7219.Matrix8x8(spi, Pin('X5'), 8)
display.text('12345678',0,0,1)
display.show()

Framebuf shapes and text

display.fill(0)
display.show()

display.pixel(0,0,1)
display.pixel(1,1,1)
display.hline(0,4,8,1)
display.vline(4,0,8,1)
display.line(8, 0, 16, 8, 1)
display.rect(17,1,6,6,1)
display.fill_rect(25,1,6,6,1)
display.show()

display.fill(0)
display.text('dead',0,0,1)
display.text('beef',32,0,1)
display.show()

display.fill(0)
display.text('12345678',0,0,1)
display.show()
display.scroll(-8,0) # 23456788
display.scroll(-8,0) # 34567888
display.show()

ESP8266 Examples

Default baud rate of 80Mhz was introducing errors, dropped from 10Mhz and it works consistently.

import max7219
from machine import Pin, SPI
spi = SPI(1, baudrate=10000000, polarity=0, phase=0)
display = max7219.Matrix8x8(spi, Pin(15), 4)
display.brightness(0)
display.fill(0)
display.text('1234',0,0,1)
display.show()

ESP32 Examples

Default baud rate of 80Mhz was introducing errors, dropped from 10Mhz and it works consistently.

import max7219
from machine import Pin, SPI
spi = SPI(1, baudrate=10000000, polarity=1, phase=0, sck=Pin(4), mosi=Pin(2))
ss = Pin(5, Pin.OUT)
display = max7219.Matrix8x8(spi, ss, 4)
display.text('1234',0,0,1)
display.show()

Connections

PyBoard	max7219 8x8 LED Matrix
VIN	VCC
GND	GND
X8 MOSI	DIN
X5 CS	CS
X6 SCK	CLK

Wemos D1 Mini	max7219 8x8 LED Matrix
5V	VCC
GND	GND
D7 MOSI (GPIO13)	DIN
D8 CS (GPIO15)	CS
D5 SCK (GPIO14)	CLK

ESP32	max7219 8x8 LED Matrix
5V	VCC
GND	GND
D2 MOSI	DIN
D5 CS	CS
D4 SCK	CLK

Links

• Based on deshipu's max7219.py
• micropython.org
• Docs on framebuf

License

Licensed under the MIT License.