Uptime QR Code

uptime_qr.py

# SPDX-FileCopyrightText: 2021 Randall Bohn
#
# SPDX-Licence-Identifier: MIT

"Uptime QR Code"
import time
import displayio

from adafruit_featherwing import tft_featherwing_35
from adafruit_bitmap_font.bitmap_font import load_font
from adafruit_display_text.label import Label
from adafruit_miniqr import QRCode

displayio.release_displays()
wing = tft_featherwing_35.TFTFeatherWing35()
display = wing.display
font = load_font("/fonts/Arial-12.pcf")
palette = displayio.Palette(2)
palette[0] = 0x888888

def uptime():
    now = time.monotonic()
    return b"%d:%02d:%02d" % (now // 3600, now % 3600 // 60, now % 60)

def qrnow():
    qr = QRCode(qr_type=2)
    qr.add_data(uptime())
    qr.make()
    return qr

def fit_bitmap(size):
    return displayio.Bitmap(size,size,2)

def imprint(qrcode, bitmap=None):
    border = 2
    m = qrcode.matrix
    if bitmap == None:
        print("creating bitmap")
        bitmap = fit_bitmap(m.width+border*2)
    for y in range(m.height):
        for x in range(m.width):
            bitmap[border+x,border+y] = m[x,y] != 0
    return bitmap

label = Label(font, text="Starting...", x=12, y=display.height * 3//8)
splash = displayio.Group(scale=2)
splash.append(label)

bitmap = imprint(qrnow())
grid = displayio.TileGrid(bitmap, pixel_shader=palette, 
    x=display.width//4-bitmap.width//2, y=display.height * 1 // 8)
splash.append(grid)

display.show(splash)

while True:
    now = time.monotonic()
    if int(now % 5) == 0:
        imprint(qrnow(), bitmap)
    label.text = "Uptime: "+uptime().decode('utf-8')
    time.sleep(1)