3D Printed Mount
You can refer to the 3D Printing page in the Getting Started with Microsoft Azure and CircuitPython guide to print a mount for the Feather and BME688.
First, setup your Feather ESP32-S2 TFT with CircuitPython. Then, you can access the code and necessary libraries by downloading the Project Bundle.
To do this, click on the Download Project Bundle button in the window below. It will download as a zipped folder.
# SPDX-FileCopyrightText: 2022 Liz Clark for Adafruit Industries
# SPDX-License-Identifier: MIT
import json
import time
import digitalio
import supervisor
import simpleio
import vectorio
import board
import terminalio
import rtc
import socketpool
import wifi
import displayio
import adafruit_ntp
from adafruit_display_text import bitmap_label, wrap_text_to_lines
from adafruit_bitmap_font import bitmap_font
from adafruit_azureiot import IoTHubDevice
import adafruit_bme680
from adafruit_lc709203f import LC709203F, PackSize
# Get wifi details and more from a secrets.py file
try:
from secrets import secrets
except ImportError:
print("WiFi secrets are kept in secrets.py, please add them there!")
raise
print("Connecting to WiFi...")
wifi.radio.connect(secrets["ssid"], secrets["password"])
print("Connected to WiFi!")
# ntp clock - update tz_offset to your timezone
pool = socketpool.SocketPool(wifi.radio)
ntp = adafruit_ntp.NTP(pool, tz_offset=0)
rtc.RTC().datetime = ntp.datetime
if time.localtime().tm_year < 2022:
print("Setting System Time in UTC")
rtc.RTC().datetime = ntp.datetime
else:
print("Year seems good, skipping set time.")
esp = None
pool = socketpool.SocketPool(wifi.radio)
# Create an IoT Hub device client and connect
device = IoTHubDevice(pool, esp, secrets["device_connection_string"])
print("Connecting to Azure IoT Hub...")
# Connect to IoT Central
device.connect()
print("Connected to Azure IoT Hub!")
cal = ntp.datetime
year = cal[0]
mon = cal[1]
day = cal[2]
hour = cal[3]
minute = cal[4]
i2c = board.I2C() # uses board.SCL and board.SDA
# i2c = board.STEMMA_I2C() # For using the built-in STEMMA QT connector on a microcontroller
bme680 = adafruit_bme680.Adafruit_BME680_I2C(i2c, debug=False)
# change this to match the location's pressure (hPa) at sea level
bme680.sea_level_pressure = 1013.25
temperature_offset = -5
# Create sensor object, using the board's default I2C bus.
i2c = board.I2C() # uses board.SCL and board.SDA
# i2c = board.STEMMA_I2C() # For using the built-in STEMMA QT connector on a microcontroller
battery_monitor = LC709203F(i2c)
# Update to match the mAh of your battery for more accurate readings.
# Can be MAH100, MAH200, MAH400, MAH500, MAH1000, MAH2000, MAH3000.
# Choose the closest match. Include "PackSize." before it, as shown.
battery_monitor.pack_size = PackSize.MAH2000
temp = int((bme680.temperature * 9/5) + (32 + temperature_offset))
humidity = int(bme680.relative_humidity)
pressure = int(bme680.pressure)
battery = battery_monitor.cell_percent
# setup boot button as input
button = digitalio.DigitalInOut(board.BUTTON)
button.switch_to_input(pull=digitalio.Pull.UP)
# display setup
display = board.DISPLAY
palette0 = displayio.Palette(2)
palette0[0] = 0x00FF00
palette0[1] = 0xFF0000
# load bitmap
bitmap = displayio.OnDiskBitmap("/bmeTFT.bmp")
tile_grid = displayio.TileGrid(bitmap, pixel_shader=bitmap.pixel_shader)
group = displayio.Group()
group.append(tile_grid)
# rectangle for battery life monitor
# vectorio allows for resizing in the loop
rect = vectorio.Rectangle(pixel_shader=palette0, width=22, height=10, x=12, y=116, color_index = 0)
group.append(rect)
# bitmap font
font_file = "/roundedHeavy-26.bdf"
font = bitmap_font.load_font(font_file)
# text elements
temp_text = bitmap_label.Label(font, text="%0.1f° F" % temp, x=20, y=80, color=0xFFFFFF)
humid_text = bitmap_label.Label(font, text="%0.1f %%" % humidity, x=95, y=80, color=0xFFFFFF)
press_text = bitmap_label.Label(font, text="%0.2f" % pressure, x=170, y=80, color=0xFFFFFF)
time_text = bitmap_label.Label(terminalio.FONT,
text="\n".join(wrap_text_to_lines
("Data sent on %s/%s/%s at %s:%s" % (mon,day,year,hour,minute), 20)),
x=125, y=105, color=0xFFFFFF)
group.append(temp_text)
group.append(humid_text)
group.append(press_text)
group.append(time_text)
display.show(group)
# clock to count down to sending data to Azure
azure_clock = 500
# clock to count down to updating TFT
feather_clock = 30
# button debounce state
button_pressed = False
while True:
try:
if button.value and button_pressed:
button_pressed = False
if not button.value and not button_pressed:
print("getting msg")
# pack message
message = {"Temperature": temp,
"Humidity": humidity,
"Pressure": pressure,
"BatteryPercent": battery,
"FeatherConnected": 1}
print("sending json")
device.send_device_to_cloud_message(json.dumps(message))
print("data sent")
# read BME sensor
temp = int((bme680.temperature * 9/5) + (32 + temperature_offset))
humidity = int(bme680.relative_humidity)
pressure = int(bme680.pressure)
# log battery %
battery = battery_monitor.cell_percent
# map range of battery charge to rectangle size on screen
battery_display = round(simpleio.map_range(battery, 0, 100, 0, 22))
# update rectangle to reflect battery charge
rect.width = int(battery_display)
# if below 20%, change rectangle color to red
if battery_monitor.cell_percent < 20:
rect.color_index = 1
# when the azure clock runs out
if azure_clock > 500:
print("getting ntp date/time")
cal = ntp.datetime
year = cal[0]
mon = cal[1]
day = cal[2]
hour = cal[3]
minute = cal[4]
time.sleep(2)
print("getting msg")
# pack message
message = {"Temperature": temp,
"Humidity": humidity,
"Pressure": pressure,
"BatteryPercent": battery}
print("sending json")
device.send_device_to_cloud_message(json.dumps(message))
print("data sent")
clock_view = "%s:%s" % (hour, minute)
if minute < 10:
clock_view = "%s:0%s" % (hour, minute)
print("updating time text")
time_text.text="\n".join(wrap_text_to_lines
("Data sent on %s/%s/%s at %s" % (mon,day,year,clock_view), 20))
# reset azure clock
azure_clock = 0
# when the feather clock runs out
if feather_clock > 30:
print("updating screen")
temp_text.text = "%0.1f° F" % temp
humid_text.text = "%0.1f %%" % humidity
press_text.text = "%0.2f" % pressure
# reset feather clock
feather_clock = 0
# if no clocks are running out
# increase counts by 1
else:
feather_clock += 1
azure_clock += 1
# ping azure
device.loop()
# if something disrupts the loop, reconnect
# pylint: disable=broad-except
except (ValueError, RuntimeError, OSError, ConnectionError) as e:
print("Network error, reconnecting\n", str(e))
time.sleep(60)
supervisor.reload()
continue
# delay
time.sleep(1)
Upload the Code and Libraries to the ESP32-S2 TFT Feather
After downloading the Project Bundle, plug your ESP32-S2 TFT Feather into the computer's USB port with a known good USB data+power cable. You should see a new flash drive appear in the computer's File Explorer or Finder (depending on your operating system) called CIRCUITPY. Unzip the folder and copy the following items to the ESP32-S2 TFT Feather's CIRCUITPY drive.
- lib folder
- roundedHeavy-26.bdf
- bmeTFT.bmp
- code.py
Your ESP32-S2 TFT Feather CIRCUITPY drive should look like this after copying the lib folder, the bmeTFT.bmp image file, the roundedHeavy-26.bdf bitmap font file, and the code.py file.
secrets.py
You will need to create and add a secrets.py file to your CIRCUITPY drive. Your secrets.py file will need to include the following information:
secrets = {
'ssid' : 'YOUR-SSID-HERE',
'password' : 'YOUR-SSID-PASSWORD-HERE',
'device_connection_string' : 'YOUR-DEVICE-CONNECTION-STRING-HERE'
}
You'll locate your Primary Connection String from your devices page in your IoT Hub. Make sure to refer to the Add IoT Hub Devices page in this guide to see the process for accessing the Primary Connection String.
