Overview

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Is the weather outside delightful? Or is it frightful? And what about in the coming days? In this guide we'll show you how to use an Adafruit MagTag to create a weather display for today and future conditions.

Using the MagTag's WiFi capability, we connect to the OpenWeatherMap service and get weather information. We then parse that and display it up in a nice summary.

Deep sleep is also used to only run the update once a day around midnight, so we can run for many weeks on one charge

Parts

Here are the parts you'll need for this project. You can get them individually:

Angled shot of Adafruit MagTag development board with ESP32-S2 and E-Ink display.
The Adafruit MagTag combines the new ESP32-S2 wireless module and a 2.9" grayscale E-Ink display to make a low-power IoT display that can show data on its screen even when power...
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Lithium Ion Polymer Battery 3.7v 420mAh with JST 2-PH connector and short cable
Lithium-ion polymer (also known as 'lipo' or 'lipoly') batteries are thin, light, and powerful. The output ranges from 4.2V when completely charged to 3.7V. This...
$6.95
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Angled shot of four magnet feet.
Got a glorious RGB Matrix project you want to mount and display in your workspace or home? If you have one of the matrix panels listed below, you'll need a pack of these...
$2.50
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Add to Cart

OR these items are also available together as a kit:

MagTag dev board with enclosure pieces, four magnet feet, and lipoly battery
The Adafruit MagTag combines the new ESP32-S2 wireless module and a 2.9" grayscale E-Ink display to make a low-power IoT display that can show data on its screen...
Out of Stock
Out of Stock

Install CircuitPython

CircuitPython is a derivative of MicroPython designed to simplify experimentation and education on low-cost microcontrollers. It makes it easier than ever to get prototyping by requiring no upfront desktop software downloads. Simply copy and edit files on the CIRCUITPY drive to iterate.

Set Up CircuitPython

Follow the steps to get CircuitPython installed on your MagTag.

Click the link above and download the latest .BIN and .UF2 file

(depending on how you program the ESP32S2 board you may need one or the other, might as well get both)

Download and save it to your desktop (or wherever is handy).

Plug your MagTag into your computer using a known-good USB cable.

A lot of people end up using charge-only USB cables and it is very frustrating! So make sure you have a USB cable you know is good for data sync.

Option 1 - Load with UF2 Bootloader

This is by far the easiest way to load CircuitPython. However it requires your board has the UF2 bootloader installed. Some early boards do not (we hadn't written UF2 yet!) - in which case you can load using the built in ROM bootloader.

Still, try this first!

Try Launching UF2 Bootloader

Loading CircuitPython by drag-n-drop UF2 bootloader is the easier way and we recommend it. If you have a MagTag where the front of the board is black, your MagTag came with UF2 already on it.

Launch UF2 by double-clicking the Reset button (the one next to the USB C port). You may have to try a few times to get the timing right.

If the UF2 bootloader is installed, you will see a new disk drive appear called MAGTAGBOOT

Copy the UF2 file you downloaded at the first step of this tutorial onto the MAGTAGBOOT drive

If you're using Windows and you get an error at the end of the file copy that says Error from the file copy, Error 0x800701B1: A device which does not exist was specified. You can ignore this error, the bootloader sometimes disconnects without telling Windows, the install completed just fine and you can continue. If its really annoying, you can also upgrade the bootloader (the latest version of the UF2 bootloader fixes this warning)

Your board should auto-reset into CircuitPython, or you may need to press reset. A CIRCUITPY drive will appear. You're done! Go to the next pages.

Option 2 - Use esptool to load BIN file

If you have an original MagTag with while soldermask on the front, we didn't have UF2 written for the ESP32S2 yet so it will not come with the UF2 bootloader.

You can upload with esptool to the ROM (hardware) bootloader instead!

Follow the initial steps found in the Run esptool and check connection section of the ROM Bootloader page to verify your environment is set up, your board is successfully connected, and which port it's using.

In the final command to write a binary file to the board, replace the port with your port, and replace "firmware.bin" with the the file you downloaded above.

The output should look something like the output in the image.

Press reset to exit the bootloader.

Your CIRCUITPY drive should appear!

You're all set! Go to the next pages.

Option 3 - Use Chrome Browser To Upload BIN file

If for some reason you cannot get esptool to run, you can always try using the Chrome-browser version of esptool we have written. This is handy if you don't have Python on your computer, or something is really weird with your setup that makes esptool not run (which happens sometimes and isn't worth debugging!) You can follow along on the Web Serial ESPTool page and either load the UF2 bootloader and then come back to Option 1 on this page, or you can download the CircuitPython BIN file directly using the tool in the same manner as the bootloader.

CircuitPython Internet Test

One of the great things about the ESP32 is the built-in WiFi capabilities. This page covers the basics of getting connected using CircuitPython.

The first thing you need to do is update your code.py to the following. Click the Download Project Bundle button below to download the necessary libraries and the code.py file in a zip file. Extract the contents of the zip file, and copy the entire lib folder and the code.py file to your CIRCUITPY drive.

Download Project Bundle
Copy Code 
# SPDX-FileCopyrightText: 2020 Brent Rubell for Adafruit Industries
#
# SPDX-License-Identifier: MIT

import ipaddress
import ssl
import wifi
import socketpool
import adafruit_requests

# URLs to fetch from
TEXT_URL = "http://wifitest.adafruit.com/testwifi/index.html"
JSON_QUOTES_URL = "https://www.adafruit.com/api/quotes.php"
JSON_STARS_URL = "https://api.github.com/repos/adafruit/circuitpython"

# 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("ESP32-S2 WebClient Test")

print("My MAC addr:", [hex(i) for i in wifi.radio.mac_address])

print("Available WiFi networks:")
for network in wifi.radio.start_scanning_networks():
    print("\t%s\t\tRSSI: %d\tChannel: %d" % (str(network.ssid, "utf-8"),
            network.rssi, network.channel))
wifi.radio.stop_scanning_networks()

print("Connecting to %s"%secrets["ssid"])
wifi.radio.connect(secrets["ssid"], secrets["password"])
print("Connected to %s!"%secrets["ssid"])
print("My IP address is", wifi.radio.ipv4_address)

ipv4 = ipaddress.ip_address("8.8.4.4")
print("Ping google.com: %f ms" % (wifi.radio.ping(ipv4)*1000))

pool = socketpool.SocketPool(wifi.radio)
requests = adafruit_requests.Session(pool, ssl.create_default_context())

print("Fetching text from", TEXT_URL)
response = requests.get(TEXT_URL)
print("-" * 40)
print(response.text)
print("-" * 40)

print("Fetching json from", JSON_QUOTES_URL)
response = requests.get(JSON_QUOTES_URL)
print("-" * 40)
print(response.json())
print("-" * 40)

print()

print("Fetching and parsing json from", JSON_STARS_URL)
response = requests.get(JSON_STARS_URL)
print("-" * 40)
print("CircuitPython GitHub Stars", response.json()["stargazers_count"])
print("-" * 40)

print("done")
View on GitHub

Your CIRCUITPY drive should resemble the following.

CIRCUITPY

To get connected, the next thing you need to do is update the secrets.py file.

Secrets File

We expect people to share tons of projects as they build CircuitPython WiFi widgets. What we want to avoid is people accidentally sharing their passwords or secret tokens and API keys. So, we designed all our examples to use a secrets.py file, that is on your CIRCUITPY drive, to hold secret/private/custom data. That way you can share your main project without worrying about accidentally sharing private stuff.

The initial secrets.py file on your CIRCUITPY drive should look like this:

Download Project Bundle
Copy Code 
# SPDX-FileCopyrightText: 2020 Adafruit Industries
#
# SPDX-License-Identifier: Unlicense

# This file is where you keep secret settings, passwords, and tokens!
# If you put them in the code you risk committing that info or sharing it

secrets = {
    'ssid' : 'home_wifi_network',
    'password' : 'wifi_password',
    'aio_username' : 'my_adafruit_io_username',
    'aio_key' : 'my_adafruit_io_key',
    'timezone' : "America/New_York", # http://worldtimeapi.org/timezones
    }
View on GitHub

Inside is a Python dictionary named secrets with a line for each entry. Each entry has an entry name (say 'ssid') and then a colon to separate it from the entry key ('home_wifi_network') and finally a comma (,).

At a minimum you'll need to adjust the ssid and password for your local WiFi setup so do that now!

As you make projects you may need more tokens and keys, just add them one line at a time. See for example other tokens such as one for accessing GitHub or the Hackaday API. Other non-secret data like your timezone can also go here, just cause its called secrets doesn't mean you can't have general customization data in there!

For the correct time zone string, look at http://worldtimeapi.org/timezones and remember that if your city is not listed, look for a city in the same time zone, for example Boston, New York, Philadelphia, Washington DC, and Miami are all on the same time as New York.

Of course, don't share your secrets.py - keep that out of GitHub, Discord or other project-sharing sites.

Don't share your secrets.py file, it has your passwords and API keys in it!

If you connect to the serial console, you should see something like the following:

adafruit_products_1__screen__Users_brentrubell__screen_.png

In order, the example code...

Checks the ESP32's MAC address.

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print("My MAC addr:", [hex(i) for i in wifi.radio.mac_address])

Performs a scan of all access points and prints out the access point's name (SSID), signal strength (RSSI), and channel.

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print("Avaliable WiFi networks:")
for network in wifi.radio.start_scanning_networks():
    print("\t%s\t\tRSSI: %d\tChannel: %d" % (str(network.ssid, "utf-8"),
            network.rssi, network.channel))
wifi.radio.stop_scanning_networks()

Connects to the access point you defined in the secrets.py file, prints out its local IP address, and attempts to ping google.com to check its network connectivity. 

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print("Connecting to %s"%secrets["ssid"])
wifi.radio.connect(secrets["ssid"], secrets["password"])
print(print("Connected to %s!"%secrets["ssid"]))
print("My IP address is", wifi.radio.ipv4_address)

ipv4 = ipaddress.ip_address("8.8.4.4")
print("Ping google.com: %f ms" % wifi.radio.ping(ipv4))

The code creates a socketpool using the wifi radio's available sockets. This is performed so we don't need to re-use sockets. Then, it initializes a a new instance of the requests interface - which makes getting data from the internet really really easy.

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pool = socketpool.SocketPool(wifi.radio)
requests = adafruit_requests.Session(pool, ssl.create_default_context())

To read in plain-text from a web URL, call requests.get - you may pass in either a http, or a https url for SSL connectivity. 

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print("Fetching text from", TEXT_URL)
response = requests.get(TEXT_URL)
print("-" * 40)
print(response.text)
print("-" * 40)

Requests can also display a JSON-formatted response from a web URL using a call to requests.get. 

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print("Fetching json from", JSON_QUOTES_URL)
response = requests.get(JSON_QUOTES_URL)
print("-" * 40)
print(response.json())
print("-" * 40)

Finally, you can fetch and parse a JSON URL using requests.get. This code snippet obtains the stargazers_count field from a call to the GitHub API.

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print("Fetching and parsing json from", JSON_STARS_URL)
response = requests.get(JSON_STARS_URL)
print("-" * 40)
print("CircuitPython GitHub Stars", response.json()["stargazers_count"])
print("-" * 40)

OK you now have your ESP32 board set up with a proper secrets.py file and can connect over the Internet. If not, check that your secrets.py file has the right ssid and password and retrace your steps until you get the Internet connectivity working!

Project Code

Here is the project code along with some additional setup needed.

Weather Icons

The icons used in this project were inspired by this other EPD based weather project - eInk / ePaper Weather Station. They are the excellent set of Meteocons , which the author has made freely available. For this project, we converted them to gray scale, scaled them as needed, and converted to bitmap.

Open Weather Maps API Key

We'll be using OpenWeatherMap.org to retrieve the weather info through its API. In order to do so, you'll need to register for an account and get your API key.

Go to this link and register for a free account. Once registered, you'll get an email containing your API key, also known as the "openweather token".

Copy and paste this key into your secrets.py file that is on the root level of your CIRCUITPY drive. Name the entry openweather_token, ex:

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'openweather_token' : 'my_openweather_token',

It'll look something like this

'openweather_token' : 'b218dde228d7be12f16bf4640208b9f5',

this is not a valid token, you have to get your own!

It may take some time for your Open Weather Maps API key to become active - tens of minutes or even hours.

Set Location

We will also use secrets.py to set your location. To do so, add new entry called openweather_location and specify either your city name and country code:

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'openweather_location' : 'Thief River Falls, US',

or by using a two tuple of latitude and longitude:

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'openweather_location' : (47.6062, -122.3321),

Note that negative longitude values are use for West.

You can verify your town or city is valid by visiting https://openweathermap.org/find and typing it into the box, if you get a weather report, then that's a known city! However, if you run into a situation where the city name is ambiguous (multiple same name cities), then use the latitude/longitude value to specify location.

Celsius or Fahrenheit

The units used for the temperature readings can be set to either Celsius or Fahrenheit. The units are set to Fahrenheit by default. To change to Celsius, look for this line of code:

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METRIC = False  # set to True for metric units

and change it to:

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METRIC = True  # set to True for metric units

In addition to changing temperature readings to Celsius, this will also change the wind readings to meters per second.

Secrets Summary

Your resulting secrets.py file should looking something like the example below, but with your specific values. It's OK if there are more entries - for other services, etc. But you need at least the ones shown here.

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secrets = {
    'ssid' : 'myssid',
    'password' : 'mypassword',
    'openweather_token' : 'my_openweather_token',
    'openweather_location' : 'Thief River Falls, US',
}
Don't forget to end each line with a comma.

Installing Project Code

To use with CircuitPython, you need to first install a few libraries, into the lib folder on your CIRCUITPY drive. Then you need to update code.py with the code listing below.

Thankfully, we can do this in one go. In the example below, click the Download Project Bundle button below to download the necessary libraries and the code.py file in a zip file. Extract the contents of the zip file, open the directory MagTag_Weather/ and then click on the directory that matches the version of CircuitPython you're using and copy the contents of that directory to your CIRCUITPY drive.

Note that there are two versions of the code located in subfolders:

  • onecall - Requires non-free account/API key.
  • forecast - Works with free account/API key.

See the code specific sections below for more detail. Only one version should be used at a time.

If you're having difficulty running this example, it could be because your MagTag CircuitPython firmware or library needs to be upgraded! Please be sure to follow https://learn.adafruit.com/adafruit-magtag/circuitpython to install the latest CircuitPython firmware and then also replace/update ALL the MagTag-specific libraries mentioned here https://learn.adafruit.com/adafruit-magtag/circuitpython-libraries-2

One Call API (non free)

This is the original version of the code, written when access to the One Call API was available with a free API key. The One Call API now requires the API key be associated with an Openweathermap account that's been set up for payments.

Older account/API keys may still work. For any new accounts/API keys that want a free version, the Forecast API version of the code below will likely be needed.

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# SPDX-FileCopyrightText: 2020 Carter Nelson for Adafruit Industries
#
# SPDX-License-Identifier: MIT
# pylint: disable=redefined-outer-name, eval-used, wrong-import-order

import time
import terminalio
import displayio
import adafruit_imageload
from adafruit_display_text import label
from adafruit_magtag.magtag import MagTag
from secrets import secrets

# --| USER CONFIG |--------------------------
METRIC = False  # set to True for metric units
# -------------------------------------------

# ----------------------------
# Define various assets
# ----------------------------
BACKGROUND_BMP = "/bmps/weather_bg.bmp"
ICONS_LARGE_FILE = "/bmps/weather_icons_70px.bmp"
ICONS_SMALL_FILE = "/bmps/weather_icons_20px.bmp"
ICON_MAP = ("01", "02", "03", "04", "09", "10", "11", "13", "50")
DAYS = ("Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday")
MONTHS = (
    "January",
    "February",
    "March",
    "April",
    "May",
    "June",
    "July",
    "August",
    "September",
    "October",
    "November",
    "December",
)
magtag = MagTag()

# ----------------------------
# Backgrounnd bitmap
# ----------------------------
magtag.graphics.set_background(BACKGROUND_BMP)

# ----------------------------
# Weather icons sprite sheet
# ----------------------------
icons_large_bmp, icons_large_pal = adafruit_imageload.load(ICONS_LARGE_FILE)
icons_small_bmp, icons_small_pal = adafruit_imageload.load(ICONS_SMALL_FILE)

# /////////////////////////////////////////////////////////////////////////


def get_data_source_url(api="onecall", location=None):
    """Build and return the URL for the OpenWeather API."""
    if api.upper() == "GEO":
        URL = "https://api.openweathermap.org/geo/1.0/direct?q="
        URL += location
    elif api.upper() == "GEOREV":
        URL = "https://api.openweathermap.org/geo/1.0/reverse?limit=1"
        URL += "&lat={}".format(location[0])
        URL += "&lon={}".format(location[1])
    elif api.upper() == "ONECALL":
        URL = "https://api.openweathermap.org/data/2.5/onecall?exclude=minutely,hourly,alerts"
        URL += "&lat={}".format(location[0])
        URL += "&lon={}".format(location[1])
    else:
        raise ValueError("Unknown API type: " + api)
    return URL + "&appid=" + secrets["openweather_token"]


def get_latlon(city_name):
    """Use the Geolocation API to determine lat/lon for given city."""
    magtag.url = get_data_source_url(api="geo", location=city_name)
    raw_data = eval(magtag.fetch())[0]
    return raw_data["lat"], raw_data["lon"]


def get_city(latlon_location):
    """Use the Geolocation API to determine city for given lat/lon."""
    magtag.url = get_data_source_url(api="georev", location=latlon_location)
    raw_data = eval(magtag.fetch())[0]
    return raw_data["name"] + ", " + raw_data["country"]


def get_forecast(location):
    """Use OneCall API to fetch forecast and timezone data."""
    resp = magtag.network.fetch(get_data_source_url(api="onecall", location=location))
    json_data = resp.json()
    return json_data["daily"], json_data["current"]["dt"], json_data["timezone_offset"]


def make_banner(x=0, y=0):
    """Make a single future forecast info banner group."""
    day_of_week = label.Label(terminalio.FONT, text="DAY", color=0x000000)
    day_of_week.anchor_point = (0, 0.5)
    day_of_week.anchored_position = (0, 10)

    icon = displayio.TileGrid(
        icons_small_bmp,
        pixel_shader=icons_small_pal,
        x=25,
        y=0,
        width=1,
        height=1,
        tile_width=20,
        tile_height=20,
    )

    day_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
    day_temp.anchor_point = (0, 0.5)
    day_temp.anchored_position = (50, 10)

    group = displayio.Group(x=x, y=y)
    group.append(day_of_week)
    group.append(icon)
    group.append(day_temp)

    return group


def temperature_text(tempK):
    if METRIC:
        return "{:3.0f}C".format(tempK - 273.15)
    else:
        return "{:3.0f}F".format(32.0 + 1.8 * (tempK - 273.15))


def wind_text(speedms):
    if METRIC:
        return "{:3.0f}m/s".format(speedms)
    else:
        return "{:3.0f}mph".format(2.23694 * speedms)


def update_banner(banner, data):
    """Update supplied forecast banner with supplied data."""
    banner[0].text = DAYS[time.localtime(data["dt"]).tm_wday][:3].upper()
    banner[1][0] = ICON_MAP.index(data["weather"][0]["icon"][:2])
    banner[2].text = temperature_text(data["temp"]["day"])


def update_today(data, tz_offset=0):
    """Update today info banner."""
    date = time.localtime(data["dt"])
    sunrise = time.localtime(data["sunrise"] + tz_offset)
    sunset = time.localtime(data["sunset"] + tz_offset)

    today_date.text = "{} {} {}, {}".format(
        DAYS[date.tm_wday].upper(),
        MONTHS[date.tm_mon - 1].upper(),
        date.tm_mday,
        date.tm_year,
    )
    today_icon[0] = ICON_MAP.index(data["weather"][0]["icon"][:2])
    today_morn_temp.text = temperature_text(data["temp"]["morn"])
    today_day_temp.text = temperature_text(data["temp"]["day"])
    today_night_temp.text = temperature_text(data["temp"]["night"])
    today_humidity.text = "{:3d}%".format(data["humidity"])
    today_wind.text = wind_text(data["wind_speed"])
    today_sunrise.text = "{:2d}:{:02d} AM".format(sunrise.tm_hour, sunrise.tm_min)
    today_sunset.text = "{:2d}:{:02d} PM".format(sunset.tm_hour - 12, sunset.tm_min)


def go_to_sleep(current_time):
    """Enter deep sleep for time needed."""
    # compute current time offset in seconds
    hour, minutes, seconds = time.localtime(current_time)[3:6]
    seconds_since_midnight = 60 * (hour * 60 + minutes) + seconds
    three_fifteen = (3 * 60 + 15) * 60
    # wake up 15 minutes after 3am
    seconds_to_sleep = (24 * 60 * 60 - seconds_since_midnight) + three_fifteen
    print(
        "Sleeping for {} hours, {} minutes".format(
            seconds_to_sleep // 3600, (seconds_to_sleep // 60) % 60
        )
    )
    magtag.exit_and_deep_sleep(seconds_to_sleep)


# ===========
# Location
# ===========
if isinstance(secrets["openweather_location"], str):
    # Get lat/lon using city name
    city = secrets["openweather_location"]
    print("Getting lat/lon for city:", city)
    latlon = get_latlon(city)
elif isinstance(secrets["openweather_location"], tuple):
    # Get city name using lat/lon
    latlon = secrets["openweather_location"]
    print("Getting city name for lat/lon:", latlon)
    city = get_city(latlon)
else:
    raise ValueError("Unknown location:", secrets["openweather_location"])

print("City =", city)
print("Lat/Lon = ", latlon)

# ===========
# U I
# ===========
today_date = label.Label(terminalio.FONT, text="?" * 30, color=0x000000)
today_date.anchor_point = (0, 0)
today_date.anchored_position = (15, 13)

city_name = label.Label(terminalio.FONT, text=city, color=0x000000)
city_name.anchor_point = (0, 0)
city_name.anchored_position = (15, 24)

today_icon = displayio.TileGrid(
    icons_large_bmp,
    pixel_shader=icons_small_pal,
    x=10,
    y=40,
    width=1,
    height=1,
    tile_width=70,
    tile_height=70,
)

today_morn_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
today_morn_temp.anchor_point = (0.5, 0)
today_morn_temp.anchored_position = (118, 59)

today_day_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
today_day_temp.anchor_point = (0.5, 0)
today_day_temp.anchored_position = (149, 59)

today_night_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
today_night_temp.anchor_point = (0.5, 0)
today_night_temp.anchored_position = (180, 59)

today_humidity = label.Label(terminalio.FONT, text="100%", color=0x000000)
today_humidity.anchor_point = (0, 0.5)
today_humidity.anchored_position = (105, 95)

today_wind = label.Label(terminalio.FONT, text="99m/s", color=0x000000)
today_wind.anchor_point = (0, 0.5)
today_wind.anchored_position = (155, 95)

today_sunrise = label.Label(terminalio.FONT, text="12:12 PM", color=0x000000)
today_sunrise.anchor_point = (0, 0.5)
today_sunrise.anchored_position = (45, 117)

today_sunset = label.Label(terminalio.FONT, text="12:12 PM", color=0x000000)
today_sunset.anchor_point = (0, 0.5)
today_sunset.anchored_position = (130, 117)

today_banner = displayio.Group()
today_banner.append(today_date)
today_banner.append(city_name)
today_banner.append(today_icon)
today_banner.append(today_morn_temp)
today_banner.append(today_day_temp)
today_banner.append(today_night_temp)
today_banner.append(today_humidity)
today_banner.append(today_wind)
today_banner.append(today_sunrise)
today_banner.append(today_sunset)

future_banners = [
    make_banner(x=210, y=18),
    make_banner(x=210, y=39),
    make_banner(x=210, y=60),
    make_banner(x=210, y=81),
    make_banner(x=210, y=102),
]

magtag.splash.append(today_banner)
for future_banner in future_banners:
    magtag.splash.append(future_banner)

# ===========
#  M A I N
# ===========
print("Fetching forecast...")
forecast_data, utc_time, local_tz_offset = get_forecast(latlon)

print("Updating...")
update_today(forecast_data[0], local_tz_offset)
for day, forecast in enumerate(forecast_data[1:6]):
    update_banner(future_banners[day], forecast)

print("Refreshing...")
time.sleep(magtag.display.time_to_refresh + 1)
magtag.display.refresh()
time.sleep(magtag.display.time_to_refresh + 1)

print("Sleeping...")
go_to_sleep(utc_time + local_tz_offset)
#  entire code will run again after deep sleep cycle
#  similar to hitting the reset button
View on GitHub

Forecast API (free)

This is a newer version of the code that uses the still free 5 Day / 3 Hour Forecast API. It attempts to provide the same informational display as the original version of the code. However, since there are some differences in the nature of the data returned by the two API's, there are some caveats.

  • The forecast is for only four days, not five. That's because one of the "5 days" is the current day.
  • Weather conditions forecasted for noon local time are used as "daily forecast".
Download Project Bundle
Copy Code 
# SPDX-FileCopyrightText: 2020 Carter Nelson for Adafruit Industries
#
# SPDX-License-Identifier: MIT
# pylint: disable=redefined-outer-name, eval-used, wrong-import-order

import time
import terminalio
import displayio
import adafruit_imageload
from adafruit_display_text import label
from adafruit_magtag.magtag import MagTag
from secrets import secrets

# --| USER CONFIG |--------------------------
METRIC = False  # set to True for metric units
# -------------------------------------------

# ----------------------------
# Define various assets
# ----------------------------
BACKGROUND_BMP = "/bmps/weather_bg.bmp"
ICONS_LARGE_FILE = "/bmps/weather_icons_70px.bmp"
ICONS_SMALL_FILE = "/bmps/weather_icons_20px.bmp"
ICON_MAP = ("01", "02", "03", "04", "09", "10", "11", "13", "50")
DAYS = ("Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday")
MONTHS = (
    "January",
    "February",
    "March",
    "April",
    "May",
    "June",
    "July",
    "August",
    "September",
    "October",
    "November",
    "December",
)
magtag = MagTag()

# ----------------------------
# Backgrounnd bitmap
# ----------------------------
magtag.graphics.set_background(BACKGROUND_BMP)

# ----------------------------
# Weather icons sprite sheet
# ----------------------------
icons_large_bmp, icons_large_pal = adafruit_imageload.load(ICONS_LARGE_FILE)
icons_small_bmp, icons_small_pal = adafruit_imageload.load(ICONS_SMALL_FILE)

# /////////////////////////////////////////////////////////////////////////


def get_data_source_url(api="forecast", location=None):
    """Build and return the URL for the OpenWeather API."""
    if location is None:
        raise ValueError("Must specify location.")
    if api.upper() == "GEO":
        URL = "https://api.openweathermap.org/geo/1.0/direct?q="
        URL += location
    elif api.upper() == "GEOREV":
        URL = "https://api.openweathermap.org/geo/1.0/reverse?limit=1"
        URL += "&lat={}".format(location[0])
        URL += "&lon={}".format(location[1])
    elif api.upper() == "FORECAST":
        URL = "https://api.openweathermap.org/data/2.5/forecast?"
        URL += "&lat={}".format(location[0])
        URL += "&lon={}".format(location[1])
    elif api.upper() == "CURRENT":
        URL = "https://api.openweathermap.org/data/2.5/weather?"
        URL += "&lat={}".format(location[0])
        URL += "&lon={}".format(location[1])
    else:
        raise ValueError("Unknown API type: " + api)
    return URL + "&appid=" + secrets["openweather_token"]


def get_latlon(city_name):
    """Use the Geolocation API to determine lat/lon for given city."""
    magtag.url = get_data_source_url(api="geo", location=city_name)
    raw_data = eval(magtag.fetch())[0]
    return raw_data["lat"], raw_data["lon"]


def get_city(latlon_location):
    """Use the Geolocation API to determine city for given lat/lon."""
    magtag.url = get_data_source_url(api="georev", location=latlon_location)
    raw_data = eval(magtag.fetch())[0]
    return raw_data["name"] + ", " + raw_data["country"]


def get_approx_time(latlon_location):
    magtag.url = get_data_source_url(api="current", location=latlon_location)
    raw_data = eval(magtag.fetch())
    return raw_data["dt"] + raw_data["timezone"]


def get_forecast(location):
    """Use Forecast API to fetch weather data and return a "daily" forecast.
    NOTE: The data query is assumed to have been done at ~2AM local time so that
    the forecast data results are (also approx):
                0  3AM
                1  6AM
                2  9AM
                3 12PM
                4  3PM
                5  6PM
                6  9PM
                7 12AM
                :   :
                (etc.)
    """
    resp = magtag.network.fetch(get_data_source_url(api="forecast", location=location))
    json_data = resp.json()
    # build "daily" forecast data (similar to Onecall API)
    # it is assumed the first entry in the list is for ~3AM local
    # and the list is 40 entries at 3 hours intervals
    #     index  local_time
    #       0        3AM
    #       1        6AM
    #       2        9AM
    #       3       12PM
    #       4        3PM
    #       5        6PM
    #       6        9PM
    #       7       12AM
    #      etc.     etc.
    if json_data["cnt"] != 40:
        raise RuntimeError("Unexpected forecast response length.")
    timezone_offset = json_data["city"]["timezone"]
    daily_data = []
    # use the 12PM values from each day, access via direct indexing (slice)
    for data in json_data["list"][3::8]:
        daily_data.append(
            {
                "dt": data["dt"] + timezone_offset,
                "weather": data["weather"],
                "temp": {"day": data["main"]["temp"]},
            }
        )
    # add extra data for day 0 (current day)
    daily_data[0]["sunrise"] = json_data["city"]["sunrise"] + timezone_offset
    daily_data[0]["sunset"] = json_data["city"]["sunset"] + timezone_offset
    daily_data[0]["temp"] = {
        "morn": json_data["list"][2]["main"]["temp"],
        "day": json_data["list"][4]["main"]["temp"],
        "night": json_data["list"][6]["main"]["temp"],
    }
    daily_data[0]["humidity"] = json_data["list"][3]["main"]["humidity"]
    daily_data[0]["wind_speed"] = json_data["list"][3]["wind"]["speed"]

    return daily_data


def make_banner(x=0, y=0):
    """Make a single future forecast info banner group."""
    day_of_week = label.Label(terminalio.FONT, text="DAY", color=0x000000)
    day_of_week.anchor_point = (0, 0.5)
    day_of_week.anchored_position = (0, 10)

    icon = displayio.TileGrid(
        icons_small_bmp,
        pixel_shader=icons_small_pal,
        x=25,
        y=0,
        width=1,
        height=1,
        tile_width=20,
        tile_height=20,
    )

    day_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
    day_temp.anchor_point = (0, 0.5)
    day_temp.anchored_position = (50, 10)

    group = displayio.Group(x=x, y=y)
    group.append(day_of_week)
    group.append(icon)
    group.append(day_temp)

    return group


def temperature_text(tempK):
    if METRIC:
        return "{:3.0f}C".format(tempK - 273.15)
    else:
        return "{:3.0f}F".format(32.0 + 1.8 * (tempK - 273.15))


def wind_text(speedms):
    if METRIC:
        return "{:3.0f}m/s".format(speedms)
    else:
        return "{:3.0f}mph".format(2.23694 * speedms)


def update_banner(banner, data):
    """Update supplied forecast banner with supplied data."""
    banner[0].text = DAYS[time.localtime(data["dt"]).tm_wday][:3].upper()
    banner[1][0] = ICON_MAP.index(data["weather"][0]["icon"][:2])
    banner[2].text = temperature_text(data["temp"]["day"])


def update_today(data):
    """Update today info banner."""
    date = time.localtime(data["dt"])
    sunrise = time.localtime(data["sunrise"])
    sunset = time.localtime(data["sunset"])

    today_date.text = "{} {} {}, {}".format(
        DAYS[date.tm_wday].upper(),
        MONTHS[date.tm_mon - 1].upper(),
        date.tm_mday,
        date.tm_year,
    )
    today_icon[0] = ICON_MAP.index(data["weather"][0]["icon"][:2])
    today_morn_temp.text = temperature_text(data["temp"]["morn"])
    today_day_temp.text = temperature_text(data["temp"]["day"])
    today_night_temp.text = temperature_text(data["temp"]["night"])
    today_humidity.text = "{:3d}%".format(data["humidity"])
    today_wind.text = wind_text(data["wind_speed"])
    today_sunrise.text = "{:2d}:{:02d} AM".format(sunrise.tm_hour, sunrise.tm_min)
    today_sunset.text = "{:2d}:{:02d} PM".format(sunset.tm_hour - 12, sunset.tm_min)


def go_to_sleep(current_time):
    """Enter deep sleep for time needed."""
    # compute current time offset in seconds
    hour, minutes, seconds = time.localtime(current_time)[3:6]
    seconds_since_midnight = 60 * (hour * 60 + minutes) + seconds
    two_fifteen = (2 * 60 + 15) * 60
    # wake up 15 minutes after 2am
    seconds_to_sleep = (24 * 60 * 60 - seconds_since_midnight) + two_fifteen
    print(
        "Sleeping for {} hours, {} minutes".format(
            seconds_to_sleep // 3600, (seconds_to_sleep // 60) % 60
        )
    )
    magtag.exit_and_deep_sleep(seconds_to_sleep)


# ===========
# Location
# ===========
if isinstance(secrets["openweather_location"], str):
    # Get lat/lon using city name
    city = secrets["openweather_location"]
    print("Getting lat/lon for city:", city)
    latlon = get_latlon(city)
elif isinstance(secrets["openweather_location"], tuple):
    # Get city name using lat/lon
    latlon = secrets["openweather_location"]
    print("Getting city name for lat/lon:", latlon)
    city = get_city(latlon)
else:
    raise ValueError("Unknown location:", secrets["openweather_location"])

print("City =", city)
print("Lat/Lon = ", latlon)

# ===========
# U I
# ===========
today_date = label.Label(terminalio.FONT, text="?" * 30, color=0x000000)
today_date.anchor_point = (0, 0)
today_date.anchored_position = (15, 13)

city_name = label.Label(terminalio.FONT, text=city, color=0x000000)
city_name.anchor_point = (0, 0)
city_name.anchored_position = (15, 24)

today_icon = displayio.TileGrid(
    icons_large_bmp,
    pixel_shader=icons_small_pal,
    x=10,
    y=40,
    width=1,
    height=1,
    tile_width=70,
    tile_height=70,
)

today_morn_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
today_morn_temp.anchor_point = (0.5, 0)
today_morn_temp.anchored_position = (118, 59)

today_day_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
today_day_temp.anchor_point = (0.5, 0)
today_day_temp.anchored_position = (149, 59)

today_night_temp = label.Label(terminalio.FONT, text="+100F", color=0x000000)
today_night_temp.anchor_point = (0.5, 0)
today_night_temp.anchored_position = (180, 59)

today_humidity = label.Label(terminalio.FONT, text="100%", color=0x000000)
today_humidity.anchor_point = (0, 0.5)
today_humidity.anchored_position = (105, 95)

today_wind = label.Label(terminalio.FONT, text="99m/s", color=0x000000)
today_wind.anchor_point = (0, 0.5)
today_wind.anchored_position = (155, 95)

today_sunrise = label.Label(terminalio.FONT, text="12:12 PM", color=0x000000)
today_sunrise.anchor_point = (0, 0.5)
today_sunrise.anchored_position = (45, 117)

today_sunset = label.Label(terminalio.FONT, text="12:12 PM", color=0x000000)
today_sunset.anchor_point = (0, 0.5)
today_sunset.anchored_position = (130, 117)

today_banner = displayio.Group()
today_banner.append(today_date)
today_banner.append(city_name)
today_banner.append(today_icon)
today_banner.append(today_morn_temp)
today_banner.append(today_day_temp)
today_banner.append(today_night_temp)
today_banner.append(today_humidity)
today_banner.append(today_wind)
today_banner.append(today_sunrise)
today_banner.append(today_sunset)

future_banners = [
    make_banner(x=210, y=18),
    make_banner(x=210, y=39),
    make_banner(x=210, y=60),
    make_banner(x=210, y=81),
]

magtag.splash.append(today_banner)
for future_banner in future_banners:
    magtag.splash.append(future_banner)

# ===========
#  M A I N
# ===========
print("Fetching forecast...")
forecast_data = get_forecast(latlon)

print("Updating...")
update_today(forecast_data[0])
for day, forecast in enumerate(forecast_data[1:5]):
    update_banner(future_banners[day], forecast)

print("Refreshing...")
time.sleep(magtag.display.time_to_refresh + 1)
magtag.display.refresh()
time.sleep(magtag.display.time_to_refresh + 1)

print("Sleeping...")
go_to_sleep(get_approx_time(latlon))
#  entire code will run again after deep sleep cycle
#  similar to hitting the reset button
View on GitHub

This guide was first published on Dec 14, 2020. It was last updated on Dec 14, 2020.