| 1 | #!/usr/bin/env python3 |
| 2 | |
| 3 | import requests |
| 4 | import ST7735 |
| 5 | import time |
| 6 | from bme280 import BME280 |
| 7 | from pms5003 import PMS5003, ReadTimeoutError |
| 8 | from subprocess import PIPE, Popen, check_output |
| 9 | from PIL import Image, ImageDraw, ImageFont |
| 10 | from fonts.ttf import RobotoMedium as UserFont |
| 11 | |
| 12 | try: |
| 13 | from smbus2 import SMBus |
| 14 | except ImportError: |
| 15 | from smbus import SMBus |
| 16 | |
| 17 | print("""luftdaten.py - Reads temperature, pressure, humidity, |
| 18 | PM2.5, and PM10 from Enviro plus and sends data to Luftdaten, |
| 19 | the citizen science air quality project. |
| 20 | |
| 21 | Note: you'll need to register with Luftdaten at: |
| 22 | https://meine.luftdaten.info/ and enter your Raspberry Pi |
| 23 | serial number that's displayed on the Enviro plus LCD along |
| 24 | with the other details before the data appears on the |
| 25 | Luftdaten map. |
| 26 | |
| 27 | Press Ctrl+C to exit! |
| 28 | |
| 29 | """) |
| 30 | |
| 31 | bus = SMBus(1) |
| 32 | |
| 33 | # Create BME280 instance |
| 34 | bme280 = BME280(i2c_dev=bus) |
| 35 | |
| 36 | # Create LCD instance |
| 37 | disp = ST7735.ST7735( |
| 38 | port=0, |
| 39 | cs=1, |
| 40 | dc=9, |
| 41 | backlight=12, |
| 42 | rotation=270, |
| 43 | spi_speed_hz=10000000 |
| 44 | ) |
| 45 | |
| 46 | # Initialize display |
| 47 | disp.begin() |
| 48 | |
| 49 | # Create PMS5003 instance |
| 50 | pms5003 = PMS5003() |
| 51 | |
| 52 | |
| 53 | # Read values from BME280 and PMS5003 and return as dict |
| 54 | def read_values(): |
| 55 | values = {} |
| 56 | cpu_temp = get_cpu_temperature() |
| 57 | raw_temp = bme280.get_temperature() |
| 58 | comp_temp = raw_temp - ((cpu_temp - raw_temp) / comp_factor) |
| 59 | values["temperature"] = "{:.2f}".format(comp_temp) |
| 60 | values["pressure"] = "{:.2f}".format(bme280.get_pressure() * 100) |
| 61 | values["humidity"] = "{:.2f}".format(bme280.get_humidity()) |
| 62 | try: |
| 63 | pm_values = pms5003.read() |
| 64 | values["P2"] = str(pm_values.pm_ug_per_m3(2.5)) |
| 65 | values["P1"] = str(pm_values.pm_ug_per_m3(10)) |
| 66 | except ReadTimeoutError: |
| 67 | pms5003.reset() |
| 68 | pm_values = pms5003.read() |
| 69 | values["P2"] = str(pm_values.pm_ug_per_m3(2.5)) |
| 70 | values["P1"] = str(pm_values.pm_ug_per_m3(10)) |
| 71 | return values |
| 72 | |
| 73 | |
| 74 | # Get CPU temperature to use for compensation |
| 75 | def get_cpu_temperature(): |
| 76 | process = Popen(['vcgencmd', 'measure_temp'], stdout=PIPE, universal_newlines=True) |
| 77 | output, _error = process.communicate() |
| 78 | return float(output[output.index('=') + 1:output.rindex("'")]) |
| 79 | |
| 80 | |
| 81 | # Get Raspberry Pi serial number to use as ID |
| 82 | def get_serial_number(): |
| 83 | with open('/proc/cpuinfo', 'r') as f: |
| 84 | for line in f: |
| 85 | if line[0:6] == 'Serial': |
| 86 | return line.split(":")[1].strip() |
| 87 | |
| 88 | |
| 89 | # Check for Wi-Fi connection |
| 90 | def check_wifi(): |
| 91 | if check_output(['hostname', '-I']): |
| 92 | return True |
| 93 | else: |
| 94 | return False |
| 95 | |
| 96 | |
| 97 | # Display Raspberry Pi serial and Wi-Fi status on LCD |
| 98 | def display_status(): |
| 99 | wifi_status = "connected" if check_wifi() else "disconnected" |
| 100 | text_colour = (255, 255, 255) |
| 101 | back_colour = (0, 170, 170) if check_wifi() else (85, 15, 15) |
| 102 | id = get_serial_number() |
| 103 | message = "{}\nWi-Fi: {}".format(id, wifi_status) |
| 104 | img = Image.new('RGB', (WIDTH, HEIGHT), color=(0, 0, 0)) |
| 105 | draw = ImageDraw.Draw(img) |
| 106 | size_x, size_y = draw.textsize(message, font) |
| 107 | x = (WIDTH - size_x) / 2 |
| 108 | y = (HEIGHT / 2) - (size_y / 2) |
| 109 | draw.rectangle((0, 0, 160, 80), back_colour) |
| 110 | draw.text((x, y), message, font=font, fill=text_colour) |
| 111 | disp.display(img) |
| 112 | |
| 113 | |
| 114 | def send_to_luftdaten(values, id): |
| 115 | pm_values = dict(i for i in values.items() if i[0].startswith("P")) |
| 116 | temp_values = dict(i for i in values.items() if not i[0].startswith("P")) |
| 117 | |
| 118 | pm_values_json = [{"value_type": key, "value": val} for key, val in pm_values.items()] |
| 119 | temp_values_json = [{"value_type": key, "value": val} for key, val in temp_values.items()] |
| 120 | |
| 121 | resp_1 = requests.post( |
| 122 | "https://api.luftdaten.info/v1/push-sensor-data/", |
| 123 | json={ |
| 124 | "software_version": "enviro-plus 0.0.1", |
| 125 | "sensordatavalues": pm_values_json |
| 126 | }, |
| 127 | headers={ |
| 128 | "X-PIN": "1", |
| 129 | "X-Sensor": id, |
| 130 | "Content-Type": "application/json", |
| 131 | "cache-control": "no-cache" |
| 132 | } |
| 133 | ) |
| 134 | |
| 135 | resp_2 = requests.post( |
| 136 | "https://api.luftdaten.info/v1/push-sensor-data/", |
| 137 | json={ |
| 138 | "software_version": "enviro-plus 0.0.1", |
| 139 | "sensordatavalues": temp_values_json |
| 140 | }, |
| 141 | headers={ |
| 142 | "X-PIN": "11", |
| 143 | "X-Sensor": id, |
| 144 | "Content-Type": "application/json", |
| 145 | "cache-control": "no-cache" |
| 146 | } |
| 147 | ) |
| 148 | |
| 149 | if resp_1.ok and resp_2.ok: |
| 150 | return True |
| 151 | else: |
| 152 | return False |
| 153 | |
| 154 | |
| 155 | # Compensation factor for temperature |
| 156 | comp_factor = 2.25 |
| 157 | |
| 158 | # Raspberry Pi ID to send to Luftdaten |
| 159 | id = "raspi-" + get_serial_number() |
| 160 | |
| 161 | # Width and height to calculate text position |
| 162 | WIDTH = disp.width |
| 163 | HEIGHT = disp.height |
| 164 | |
| 165 | # Text settings |
| 166 | font_size = 16 |
| 167 | font = ImageFont.truetype(UserFont, font_size) |
| 168 | |
| 169 | # Display Raspberry Pi serial and Wi-Fi status |
| 170 | print("Raspberry Pi serial: {}".format(get_serial_number())) |
| 171 | print("Wi-Fi: {}\n".format("connected" if check_wifi() else "disconnected")) |
| 172 | |
| 173 | time_since_update = 0 |
| 174 | update_time = time.time() |
| 175 | |
| 176 | # Main loop to read data, display, and send to Luftdaten |
| 177 | while True: |
| 178 | try: |
| 179 | time_since_update = time.time() - update_time |
| 180 | values = read_values() |
| 181 | print(values) |
| 182 | if time_since_update > 145: |
| 183 | resp = send_to_luftdaten(values, id) |
| 184 | update_time = time.time() |
| 185 | print("Response: {}\n".format("ok" if resp else "failed")) |
| 186 | display_status() |
| 187 | except Exception as e: |
| 188 | print(e) |