examples/all-in-one.py

   1 #!/usr/bin/env python3
   2
   3 import time
   4 import colorsys
   5 import os
   6 import sys
   7 import ST7735
   8 try:
   9     # Transitional fix for breaking change in LTR559
  10     from ltr559 import LTR559
  11     ltr559 = LTR559()
  12 except ImportError:
  13     import ltr559
  14
  15 from bme280 import BME280
  16 from pms5003 import PMS5003, ReadTimeoutError as pmsReadTimeoutError
  17 from enviroplus import gas
  18 from subprocess import PIPE, Popen
  19 from PIL import Image
  20 from PIL import ImageDraw
  21 from PIL import ImageFont
  22 from fonts.ttf import RobotoMedium as UserFont
  23 import logging
  24
  25 logging.basicConfig(
  26     format='%(asctime)s.%(msecs)03d %(levelname)-8s %(message)s',
  27     level=logging.INFO,
  28     datefmt='%Y-%m-%d %H:%M:%S')
  29
  30 logging.info("""all-in-one.py - Displays readings from all of Enviro plus' sensors
  31
  32 Press Ctrl+C to exit!
  33
  34 """)
  35
  36 # BME280 temperature/pressure/humidity sensor
  37 bme280 = BME280()
  38
  39 # PMS5003 particulate sensor
  40 pms5003 = PMS5003()
  41
  42 # Create ST7735 LCD display class
  43 st7735 = ST7735.ST7735(
  44     port=0,
  45     cs=1,
  46     dc=9,
  47     backlight=12,
  48     rotation=270,
  49     spi_speed_hz=10000000
  50 )
  51
  52 # Initialize display
  53 st7735.begin()
  54
  55 WIDTH = st7735.width
  56 HEIGHT = st7735.height
  57
  58 # Set up canvas and font
  59 img = Image.new('RGB', (WIDTH, HEIGHT), color=(0, 0, 0))
  60 draw = ImageDraw.Draw(img)
  61 font_size = 20
  62 font = ImageFont.truetype(UserFont, font_size)
  63
  64 message = ""
  65
  66 # The position of the top bar
  67 top_pos = 25
  68
  69
  70 # Displays data and text on the 0.96" LCD
  71 def display_text(variable, data, unit):
  72     # Maintain length of list
  73     values[variable] = values[variable][1:] + [data]
  74     # Scale the values for the variable between 0 and 1
  75     colours = [(v - min(values[variable]) + 1) / (max(values[variable])
  76                - min(values[variable]) + 1) for v in values[variable]]
  77     # Format the variable name and value
  78     message = "{}: {:.1f} {}".format(variable[:4], data, unit)
  79     logging.info(message)
  80     draw.rectangle((0, 0, WIDTH, HEIGHT), (255, 255, 255))
  81     for i in range(len(colours)):
  82         # Convert the values to colours from red to blue
  83         colour = (1.0 - colours[i]) * 0.6
  84         r, g, b = [int(x * 255.0) for x in colorsys.hsv_to_rgb(colour,
  85                    1.0, 1.0)]
  86         # Draw a 1-pixel wide rectangle of colour
  87         draw.rectangle((i, top_pos, i+1, HEIGHT), (r, g, b))
  88         # Draw a line graph in black
  89         line_y = HEIGHT - (top_pos + (colours[i] * (HEIGHT - top_pos)))\
  90                  + top_pos
  91         draw.rectangle((i, line_y, i+1, line_y+1), (0, 0, 0))
  92     # Write the text at the top in black
  93     draw.text((0, 0), message, font=font, fill=(0, 0, 0))
  94     st7735.display(img)
  95
  96
  97 # Get the temperature of the CPU for compensation
  98 def get_cpu_temperature():
  99     process = Popen(['vcgencmd', 'measure_temp'], stdout=PIPE, universal_newlines=True)
 100     output, _error = process.communicate()
 101     return float(output[output.index('=') + 1:output.rindex("'")])
 102
 103
 104 # Tuning factor for compensation. Decrease this number to adjust the
 105 # temperature down, and increase to adjust up
 106 factor = 2.25
 107
 108 cpu_temps = [get_cpu_temperature()] * 5
 109
 110 delay = 0.5  # Debounce the proximity tap
 111 mode = 0     # The starting mode
 112 last_page = 0
 113 light = 1
 114
 115 # Create a values dict to store the data
 116 variables = ["temperature",
 117              "pressure",
 118              "humidity",
 119              "light",
 120              "oxidised",
 121              "reduced",
 122              "nh3",
 123              "pm1",
 124              "pm25",
 125              "pm10"]
 126
 127 values = {}
 128
 129 for v in variables:
 130     values[v] = [1] * WIDTH
 131
 132 # The main loop
 133 try:
 134     while True:
 135         proximity = ltr559.get_proximity()
 136
 137         # If the proximity crosses the threshold, toggle the mode
 138         if proximity > 1500 and time.time() - last_page > delay:
 139             mode += 1
 140             mode %= len(variables)
 141             last_page = time.time()
 142
 143         # One mode for each variable
 144         if mode == 0:
 145             # variable = "temperature"
 146             unit = "C"
 147             cpu_temp = get_cpu_temperature()
 148             # Smooth out with some averaging to decrease jitter
 149             cpu_temps = cpu_temps[1:] + [cpu_temp]
 150             avg_cpu_temp = sum(cpu_temps) / float(len(cpu_temps))
 151             raw_temp = bme280.get_temperature()
 152             data = raw_temp - ((avg_cpu_temp - raw_temp) / factor)
 153             display_text(variables[mode], data, unit)
 154
 155         if mode == 1:
 156             # variable = "pressure"
 157             unit = "hPa"
 158             data = bme280.get_pressure()
 159             display_text(variables[mode], data, unit)
 160
 161         if mode == 2:
 162             # variable = "humidity"
 163             unit = "%"
 164             data = bme280.get_humidity()
 165             display_text(variables[mode], data, unit)
 166
 167         if mode == 3:
 168             # variable = "light"
 169             unit = "Lux"
 170             if proximity < 10:
 171                 data = ltr559.get_lux()
 172             else:
 173                 data = 1
 174             display_text(variables[mode], data, unit)
 175
 176         if mode == 4:
 177             # variable = "oxidised"
 178             unit = "kO"
 179             data = gas.read_all()
 180             data = data.oxidising / 1000
 181             display_text(variables[mode], data, unit)
 182
 183         if mode == 5:
 184             # variable = "reduced"
 185             unit = "kO"
 186             data = gas.read_all()
 187             data = data.reducing / 1000
 188             display_text(variables[mode], data, unit)
 189
 190         if mode == 6:
 191             # variable = "nh3"
 192             unit = "kO"
 193             data = gas.read_all()
 194             data = data.nh3 / 1000
 195             display_text(variables[mode], data, unit)
 196
 197         if mode == 7:
 198             # variable = "pm1"
 199             unit = "ug/m3"
 200             try:
 201                 data = pms5003.read()
 202             except pmsReadTimeoutError:
 203                 logging.warn("Failed to read PMS5003")
 204             else:
 205                 data = float(data.pm_ug_per_m3(1.0))
 206                 display_text(variables[mode], data, unit)
 207
 208         if mode == 8:
 209             # variable = "pm25"
 210             unit = "ug/m3"
 211             try:
 212                 data = pms5003.read()
 213             except pmsReadTimeoutError:
 214                 logging.warn("Failed to read PMS5003")
 215             else:
 216                 data = float(data.pm_ug_per_m3(2.5))
 217                 display_text(variables[mode], data, unit)
 218
 219         if mode == 9:
 220             # variable = "pm10"
 221             unit = "ug/m3"
 222             try:
 223                 data = pms5003.read()
 224             except pmsReadTimeoutError:
 225                 logging.warn("Failed to read PMS5003")
 226             else:
 227                 data = float(data.pm_ug_per_m3(10))
 228                 display_text(variables[mode], data, unit)
 229
 230 # Exit cleanly
 231 except KeyboardInterrupt:
 232     sys.exit(0)