Twinkle, Twinkle, little micropython star..

[easytarget]

Something I made last year;

No animations on GH discussions ☹️ but trust me; it is twinkling busily with many colors and intensities.

This is a SeeedStudio RP2040 XIAO board (thumb sized, USB-C, has an onboard NeoPixel) embedded in a translucent 3-d printed 'star'. It is currently adorning the tree in my apartment and running the following blob as main.py

from machine import Pin
from neopixel import NeoPixel
from utime import sleep_ms
from random import choice

# comment/uncomment and Modify the appropriate section below for your hardware,

# Expressif ESP32-C3 devboards have NeoPixels on GPIO8
#pixel = NeoPixel(Pin(8),1)
# SeeedStudio XIAO RP2040 (Pixel VCC is supplied via pin 11)
Pin(11, Pin.OUT).on()
pixel = NeoPixel(Pin(12), 1)

speedfactor = 50       # minimum flash interval in ms, make this lower to speed up
brightness  = 1.0      # A float between 0.0 and 1.0 that sets basic maximum brightness

# Use random indexes into tuples of possible values; this allows a 'bias' to be applied
# to favor faster and lower intensity flashes between bright long ones.
speeds = (1, 2, 3, 5)
values = (0, 1, 2, 3, 5, 7, 9, 11, 31, 63, 95, 127, 255)
colors = ((1,0,0), (1,1,0), (0,1,0), (0,1,1), (0,0,1), (1,0,1), (1,1,1))

# Now twinkle, twinkle little star..
while True:
    value = int(choice(values) * brightness)
    color = choice(colors)
    pixel[0] = [c * value for c in color]
    pixel.write()
    sleep_ms(choice(speeds) * speedfactor)

End effect is quite good, powered by a cheap 3m long USB-C cable and a wall-wart.

The star itself comes from the following .scad:

// Christmas star with cutout for Xiao RP 2040
$fn=180;

difference() {
  translate([0,0,60])
  for (a=[-140,-70,0,70,140]) {
    hull() {
      sphere(18);
      rotate([a,0,0]) translate([0,0,70]) sphere(6);
    }
  }
  linear_extrude(height=62,convexity=10)
    translate([0,-9]) square([6,18]);
}

[jonnor]

Nice! Just in time for New Years Eve :D