README.md

MLP201127 MicroPython driver (example for RPi Pico)

Python driver for Mottram Labs MLP201127 LED and 4x7 Segment Display based on MAX7219

You can find more about this driver from the maker: Round LED Bar Graph Power Display - RED - Arduino - ESP8266 - MLP201127

Based on the MAX7219, the first 4 registers are for the 4x7 digit LED dispay and the following 3 are for the surrounding LEDs, one for each colour. There is a super simple implementation for the onboard speaker too.

Implementation inherits from micropython-MAX7219 which provides excellent support for the LED digits and I added an additional methods to initialise using specific Pins, set the leds using an integer and reset.

Example Pins

Board	GPIO	RPI Pin
din	gpio3	5
cs	gpio5	7
clk	gpio2	4
spkr*	gpio7	10
vcc	vbus	40
gnd	gnd	38

** Optional - only provide pin if you have connected it

Example Code

# Import MicroPython libraries of PIN and SPI
from mlp201127 import PowerDisplay
from machine import SPI, Pin
from time import sleep

# Intialize the Pins
spi_bus = SPI(0, baudrate=10000000, polarity=1, phase=1, sck=Pin(2), mosi=Pin(3))
cs = Pin(5, Pin.OUT)
speaker = Pin(7, Pin.OUT)

display = PowerDisplay(cs, spi_bus, speaker)

# Handy python version of Arduino map function
def map_range(x, in_min, in_max, out_min, out_max):
  return (x - in_min) * (out_max - out_min) // (in_max - in_min) + out_min

# Python implementation of soak test from Mottram Labs - https://github.com/Mottramlabs/MAX7219-LED-Bar-Graph-Power-Display/blob/master/Firmware/Power_Display_Soak_Round_Type_Version_1/Power_Display_Soak_Round_Type_Version_1.ino
for yy in range(5):
    zz = 0.0
    display.tone()
    while zz < 100.1:
        sleep(0.001)
        display.number(zz)
        xx = int(zz)
        xx = map_range(xx, 0, 100, 0, 24)
        display.set_power(xx)
        zz += 0.1

Dependencies

micropython-MAX7219 - provides base support for LED digits