Adafruit NASA User Manual

PyPortal NASA Image of the Day Viewer

Created by John Park

Last updated on 2021-03-17 01:17:44 PM EDT

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Guide Contents

Guide Contents Overview

Parts

Install CircuitPython

Set up CircuitPython Quick Start! PyPortal Default Files

PyPortal CircuitPython Setup Adafruit CircuitPython Bundle Internet Connect! What's a secrets file? Connect to WiFi Requests

HTTP GET with Requests HTTP POST with Requests Advanced Requests Usage

WiFi Manager Code PyPortal NASA Image Viewer

NASA Open API Key Adafruit IO Time Server Add CircuitPython Code and Assets Editing the Code Add NASA API Key boot.py Project Code How It Works

Background Splash Screen Font JSON

Overview

SPAAAAAACE! Who doesn't want to look endlessly fascinating photos of space? !

NASA's Astronomy Picture of the Day (APOD) website provides just what the title says, a new, incredible space photo each day. Now, you can set up your PyPortal to be a dedicated viewer for these glorious images!

You'll use CircuitPython to code it, and the PyPortal library will make it simple to query the NASA Open API for the image.

Parts

Adafruit PyPortal - CircuitPython Powered Internet Display

PyPortal, our easy-to-use IoT device that allows you to create all the things for the “Internet of Things” in minutes. Make custom touch screen interface... Out of Stock

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Stock

Adafruit PyPortal Desktop Stand Enclosure Kit

PyPortal is our easy-to-use IoT device that allows you to create all the things for the “Internet of Things” in minutes. Create little pocket... $9.95 In Stock

Fully Reversible Pink/Purple USB A to micro B Cable - 1m long

This cable is not only super-fashionable, with a woven pink and purple Blinka-like pattern, it's also fully reversible! That's right, you will save seconds a day by... Out of Stock

Add to Cart

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Install CircuitPython

CircuitPython (https://adafru.it/tB7) is a derivative of MicroPython (https://adafru.it/BeZ) 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 "flash" drive to iterate.

The following instructions will show you how to install CircuitPython. If you've already installed CircuitPython but are looking to update it or reinstall it, the same steps work for that as well!

Set up CircuitPython Quick Start!

Follow this quick step-by-step for super-fast Python power :)

https://adafru.it/Egk

https://adafru.it/HFd

Click the link above to download the latest version of

CircuitPython for the PyPortal.

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

Plug your PyPortal 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.

Double-click the Reset button on the top in the middle (magenta arrow) on your board, and you will see the NeoPixel RGB LED (green arrow) turn green. If it turns red, check the USB cable, try another USB port, etc. Note: The little red LED next to the USB connector will pulse red. That's ok!

If double-clicking doesn't work the first time, try again. Sometimes it can take a few tries to get the rhythm right!

https://adafru.it/Egk

https://adafru.it/HFd

You will see a new disk drive appear called PORTALBOOT.

Drag the adafruit-circuitpython-pyportal-<whatever>.uf2 file to PORTALBOOT.

The LED will flash. Then, the PORTALBOOT drive will disappear and a new disk drive called CIRCUITPY will appear.

If you haven't added any code to your board, the only file that will be present is boot_out.txt. This is absolutely normal! It's time for you to add your code.py and get started!

That's it, you're done! :)

PyPortal Default Files

Click below to download a zip of the files that shipped on the PyPortal or PyPortal Pynt.

https://adafru.it/Env

https://adafru.it/HFf

https://adafru.it/Env

https://adafru.it/HFf

PyPortal CircuitPython Setup

To use all the amazing features of your PyPortal with CircuitPython, you must first install a number of libraries. This page covers that process.

Adafruit CircuitPython Bundle

Download the Adafruit CircuitPython Library Bundle. You can find the latest release here:

https://adafru.it/ENC

Download the adafruit-circuitpython-bundle-*.x-mpy-*.zip bundle zip file where *.x MATCHES THE VERSION OF CIRCUITPYTHON YOU INSTALLED, and unzip a folder of the same name. Inside you'll find a lib folder. You have two options:

You can add the lib folder to your CIRCUITPY drive. This will ensure you have

all the drivers

. But it will take a bunch of space on the 8 MB disk Add each library as you need it, this will reduce the space usage but you'll need to put in a little more effort.

At a minimum we recommend the following libraries, in fact we more than recommend. They're basically required. So grab them and install them into CIRCUITPY/lib now!

adafruit_esp32spi - This is the library that gives you internet access via the ESP32 using (you guessed it!) SPI transport. You need this for anything Internet adafruit_requests - This library allows us to perform HTTP requests and get responses back from servers. GET/POST/PUT/PATCH - they're all in here! adafruit_pyportal - This is our friendly wrapper library that does a lot of our projects, displays graphics and text, fetches data from the internet. Nearly all of our projects depend on it!

adafruit_portalbase - This library is the base library that adafruit_pyportal library is built on top of. adafruit_touchscreen - a library for reading touches from the resistive touchscreen. Handles all the

analog noodling, rotation and calibration for you.

adafruit_io - this library helps connect the PyPortal to our free datalogging and viewing service adafruit_imageload - an image display helper, required for any graphics! adafruit_display_text - not surprisingly, it displays text on the screen adafruit_bitmap_font - we have fancy font support, and its easy to make new fonts. This library reads

and parses font files.

adafruit_slideshow - for making image slideshows - handy for quick display of graphics and sound neopixel - for controlling the onboard neopixel adafruit_adt7410 - library to read the temperature from the on-board Analog Devices ADT7410

precision temperature sensor

adafruit_sdcard - support for reading/writing data from the onboard SD card slot. adafruit_bus_device - low level support for I2C/SPI adafruit_fakerequests - This library allows you to create fake HTTP requests by using local files.

https://adafru.it/ENC

Internet Connect!

Once you have CircuitPython setup and libraries installed we can get your board connected to the Internet. Note that access to enterprise level secured WiFi networks is not currently supported, only WiFi networks that require SSID and password.

To get connected, you will need to start by creating a

secrets file

.

What's a 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 in your CIRCUITPY drive, to hold secret/private/custom data.

That way you can share your main project without worrying about accidentally sharing private stuff.

Your secrets.py file should look like this:

# 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 ssid', 'password' : 'my password', 'timezone' : "America/New_York", # http://worldtimeapi.org/timezones 'github_token' : 'fawfj23rakjnfawiefa', 'hackaday_token' : 'h4xx0rs3kret', }

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 ssid' and finally a comma ,

At a minimum you'll need the ssid and password for your local WiFi setup. 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 it's 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 (https://adafru.it/EcP) 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.

Connect to WiFi

OK now you have your secrets setup - you can connect to the Internet. Lets use the ESP32SPI and the Requests libraries - you'll need to visit the CircuitPython bundle and install (https://adafru.it/ENC):

adafruit_bus_device

adafruit_esp32spi

adafruit_requests

neopixel

Into your lib folder. Once that's done, load up the following example using Mu or your favorite editor:

# SPDX-FileCopyrightText: 2019 ladyada for Adafruit Industries # SPDX-License-Identifier: MIT

import board import busio from digitalio import DigitalInOut import adafruit_requests as requests import adafruit_esp32spi.adafruit_esp32spi_socket as socket from adafruit_esp32spi import adafruit_esp32spi

# 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 SPI webclient test")

TEXT_URL = "http://wifitest.adafruit.com/testwifi/index.html" JSON_URL = "http://api.coindesk.com/v1/bpi/currentprice/USD.json"

# If you are using a board with pre-defined ESP32 Pins: esp32_cs = DigitalInOut(board.ESP_CS) esp32_ready = DigitalInOut(board.ESP_BUSY) esp32_reset = DigitalInOut(board.ESP_RESET)

# If you have an AirLift Shield: # esp32_cs = DigitalInOut(board.D10) # esp32_ready = DigitalInOut(board.D7) # esp32_reset = DigitalInOut(board.D5)

# If you have an AirLift Featherwing or ItsyBitsy Airlift: # esp32_cs = DigitalInOut(board.D13) # esp32_ready = DigitalInOut(board.D11) # esp32_reset = DigitalInOut(board.D12)

# If you have an externally connected ESP32: # NOTE: You may need to change the pins to reflect your wiring # esp32_cs = DigitalInOut(board.D9) # esp32_ready = DigitalInOut(board.D10) # esp32_reset = DigitalInOut(board.D5)

spi = busio.SPI(board.SCK, board.MOSI, board.MISO) esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset)

requests.set_socket(socket, esp)

if esp.status == adafruit_esp32spi.WL_IDLE_STATUS: print("ESP32 found and in idle mode") print("Firmware vers.", esp.firmware_version) print("MAC addr:", [hex(i) for i in esp.MAC_address])

for ap in esp.scan_networks(): print("\t%s\t\tRSSI: %d" % (str(ap["ssid"], "utf-8"), ap["rssi"]))

print("Connecting to AP...") while not esp.is_connected: try: esp.connect_AP(secrets["ssid"], secrets["password"]) except RuntimeError as e:

print("could not connect to AP, retrying: ", e) continue print("Connected to", str(esp.ssid, "utf-8"), "\tRSSI:", esp.rssi) print("My IP address is", esp.pretty_ip(esp.ip_address)) print( "IP lookup adafruit.com: %s" % esp.pretty_ip(esp.get_host_by_name("adafruit.com")) ) print("Ping google.com: %d ms" % esp.ping("google.com"))

# esp._debug = True print("Fetching text from", TEXT_URL) r = requests.get(TEXT_URL) print("-" * 40) print(r.text) print("-" * 40) r.close()

print() print("Fetching json from", JSON_URL) r = requests.get(JSON_URL) print("-" * 40) print(r.json()) print("-" * 40) r.close()

print("Done!")

And save it to your board, with the name code.py .

Don't forget you'll also need to create the secrets.py file as seen above, with your WiFi ssid and password.

In a serial console, you should see something like the following. For more information about connecting with a serial console, view the guide Connecting to the Serial Console (https://adafru.it/Bec).

In order, the example code...

Initializes the ESP32 over SPI using the SPI port and 3 control pins:

esp32_cs = DigitalInOut(board.ESP_CS) esp32_ready = DigitalInOut(board.ESP_BUSY) esp32_reset = DigitalInOut(board.ESP_RESET)

spi = busio.SPI(board.SCK, board.MOSI, board.MISO) esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset)

Tells our requests library the type of socket we're using (socket type varies by connectivity type - we'll be using the adafruit_esp32spi_socket for this example). We'll also set the interface to an esp object. This is a little bit of a hack, but it lets us use requests like CPython does.

requests.set_socket(socket, esp)

Verifies an ESP32 is found, checks the firmware and MAC address

if esp.status == adafruit_esp32spi.WL_IDLE_STATUS: print("ESP32 found and in idle mode") print("Firmware vers.", esp.firmware_version) print("MAC addr:", [hex(i) for i in esp.MAC_address])

Performs a scan of all access points it can see and prints out the name and signal strength:

for ap in esp.scan_networks(): print("\t%s\t\tRSSI: %d" % (str(ap['ssid'], 'utf-8'), ap['rssi']))

Connects to the AP we've defined here, then prints out the local IP address, attempts to do a domain name lookup and ping google.com to check network connectivity (note sometimes the ping fails or takes a while, this isn't a big deal)

print("Connecting to AP...") while not esp.is_connected: try: esp.connect_AP(secrets["ssid"], secrets["password"]) except RuntimeError as e: print("could not connect to AP, retrying: ", e) continue print("Connected to", str(esp.ssid, "utf-8"), "\tRSSI:", esp.rssi) print("My IP address is", esp.pretty_ip(esp.ip_address)) print( "IP lookup adafruit.com: %s" % esp.pretty_ip(esp.get_host_by_name("adafruit.com"))

OK now we're getting to the really interesting part. With a SAMD51 or other large-RAM (well, over 32 KB) device, we can do a lot of neat tricks. Like for example we can implement an interface a lot like

requests (https://adafru.it/E9o) - which makes getting data

really really easy

To read in all the text from a web URL call requests.get - you can pass in https URLs for SSL connectivity

TEXT_URL = "http://wifitest.adafruit.com/testwifi/index.html" print("Fetching text from", TEXT_URL) r = requests.get(TEXT_URL) print('-'*40) print(r.text) print('-'*40) r.close()

Or, if the data is in structured JSON, you can get the json pre-parsed into a Python dictionary that can be easily queried or traversed. (Again, only for nRF52840, M4 and other high-RAM boards)

JSON_URL = "http://api.coindesk.com/v1/bpi/currentprice/USD.json" print("Fetching json from", JSON_URL) r = requests.get(JSON_URL) print('-'*40) print(r.json()) print('-'*40) r.close()

Requests

We've written a requests-like (https://adafru.it/Kpa) library for web interfacing named Adafruit_CircuitPython_Requests (https://adafru.it/FpW). This library allows you to send HTTP/1.1 requests without "crafting" them and provides helpful methods for parsing the response from the server.

# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries # SPDX-License-Identifier: MIT

# adafruit_requests usage with an esp32spi_socket import board import busio

import busio from digitalio import DigitalInOut import adafruit_esp32spi.adafruit_esp32spi_socket as socket from adafruit_esp32spi import adafruit_esp32spi import adafruit_requests as requests

# Add a secrets.py to your filesystem that has a dictionary called secrets with "ssid" and # "password" keys with your WiFi credentials. DO NOT share that file or commit it into Git or other # source control. # pylint: disable=no-name-in-module,wrong-import-order try: from secrets import secrets except ImportError: print("WiFi secrets are kept in secrets.py, please add them there!") raise

# If you are using a board with pre-defined ESP32 Pins: esp32_cs = DigitalInOut(board.ESP_CS) esp32_ready = DigitalInOut(board.ESP_BUSY) esp32_reset = DigitalInOut(board.ESP_RESET)

# If you have an externally connected ESP32: # esp32_cs = DigitalInOut(board.D9) # esp32_ready = DigitalInOut(board.D10) # esp32_reset = DigitalInOut(board.D5)

spi = busio.SPI(board.SCK, board.MOSI, board.MISO) esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset)

print("Connecting to AP...") while not esp.is_connected: try: esp.connect_AP(secrets["ssid"], secrets["password"]) except RuntimeError as e: print("could not connect to AP, retrying: ", e) continue print("Connected to", str(esp.ssid, "utf-8"), "\tRSSI:", esp.rssi)

# Initialize a requests object with a socket and esp32spi interface socket.set_interface(esp) requests.set_socket(socket, esp)

TEXT_URL = "http://wifitest.adafruit.com/testwifi/index.html" JSON_GET_URL = "http://httpbin.org/get" JSON_POST_URL = "http://httpbin.org/post"

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

print("Text Response: ", response.text) print("-" * 40) response.close()

print("Fetching JSON data from %s" % JSON_GET_URL) response = requests.get(JSON_GET_URL) print("-" * 40)

print("JSON Response: ", response.json()) print("-" * 40) response.close()

data = "31F" print("POSTing data to {0}: {1}".format(JSON_POST_URL, data))

print("POSTing data to {0}: {1}".format(JSON_POST_URL, data)) response = requests.post(JSON_POST_URL, data=data) print("-" * 40)

json_resp = response.json() # Parse out the 'data' key from json_resp dict. print("Data received from server:", json_resp["data"]) print("-" * 40) response.close()

json_data = {"Date": "July 25, 2019"} print("POSTing data to {0}: {1}".format(JSON_POST_URL, json_data)) response = requests.post(JSON_POST_URL, json=json_data) print("-" * 40)

json_resp = response.json() # Parse out the 'json' key from json_resp dict. print("JSON Data received from server:", json_resp["json"]) print("-" * 40) response.close()

The code first sets up the ESP32SPI interface. Then, it initializes a request object using an ESP32 socket and the esp object.

import board import busio from digitalio import DigitalInOut import adafruit_esp32spi.adafruit_esp32spi_socket as socket from adafruit_esp32spi import adafruit_esp32spi import adafruit_requests as requests

# If you are using a board with pre-defined ESP32 Pins: esp32_cs = DigitalInOut(board.ESP_CS) esp32_ready = DigitalInOut(board.ESP_BUSY) esp32_reset = DigitalInOut(board.ESP_RESET)

# If you have an externally connected ESP32: # esp32_cs = DigitalInOut(board.D9) # esp32_ready = DigitalInOut(board.D10) # esp32_reset = DigitalInOut(board.D5)

spi = busio.SPI(board.SCK, board.MOSI, board.MISO) esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset)

print("Connecting to AP...") while not esp.is_connected: try: esp.connect_AP(b'MY_SSID_NAME', b'MY_SSID_PASSWORD') except RuntimeError as e: print("could not connect to AP, retrying: ",e) continue print("Connected to", str(esp.ssid, 'utf-8'), "\tRSSI:", esp.rssi)

# Initialize a requests object with a socket and esp32spi interface requests.set_socket(socket, esp)

HTTP GET with Requests

The code makes a HTTP GET request to Adafruit's WiFi testing website

- http://wifitest.adafruit.com/testwifi/index.html (https://adafru.it/FpZ).

To do this, we'll pass the URL into requests.get() . We're also going to save the response

from

the server

into a variable named response .

While we requested data from the server, we'd what the server responded with. Since we already saved the server's response , we can read it back. Luckily for us, requests automatically decodes the server's

response into human-readable text, you can read it back by calling response.text .

Lastly, we'll perform a bit of cleanup by calling response.close() . This closes, deletes, and collect's the response's data.

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

print("Text Response: ", response.text) print('-'*40) response.close()

While some servers respond with text, some respond with json-formatted data consisting of attribute– value pairs.

CircuitPython_Requests can convert a JSON-formatted response from a server into a CPython dict.

object.

We can also fetch and parse json data. We'll send a HTTP get to a url we know returns a json-formatted response (instead of text data).

Then, the code calls response.json() to convert the response to a CPython dict .

print("Fetching JSON data from %s"%JSON_GET_URL) response = requests.get(JSON_GET_URL) print('-'*40)

print("JSON Response: ", response.json()) print('-'*40) response.close()

HTTP POST with Requests

Requests can also POST data to a server by calling the requests.post method, passing it a data value.

data = '31F' print("POSTing data to {0}: {1}".format(JSON_POST_URL, data)) response = requests.post(JSON_POST_URL, data=data) print('-'*40)

json_resp = response.json() # Parse out the 'data' key from json_resp dict. print("Data received from server:", json_resp['data']) print('-'*40) response.close()

You can also post json-formatted data to a server by passing json_data into the requests.post method.

json_data = {"Date" : "July 25, 2019"} print("POSTing data to {0}: {1}".format(JSON_POST_URL, json_data)) response = requests.post(JSON_POST_URL, json=json_data) print('-'*40)

json_resp = response.json() # Parse out the 'json' key from json_resp dict. print("JSON Data received from server:", json_resp['json']) print('-'*40) response.close()

Advanced Requests Usage

Want to send custom HTTP headers, parse the response as raw bytes, or handle a response's http status code in your CircuitPython code?

We've written an example to show advanced usage of the requests module below.

# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries # SPDX-License-Identifier: MIT

import board import busio from digitalio import DigitalInOut import adafruit_esp32spi.adafruit_esp32spi_socket as socket from adafruit_esp32spi import adafruit_esp32spi import adafruit_requests as requests

# Add a secrets.py to your filesystem that has a dictionary called secrets with "ssid" and # "password" keys with your WiFi credentials. DO NOT share that file or commit it into Git or other # source control. # pylint: disable=no-name-in-module,wrong-import-order try: from secrets import secrets except ImportError: print("WiFi secrets are kept in secrets.py, please add them there!") raise

# If you are using a board with pre-defined ESP32 Pins: esp32_cs = DigitalInOut(board.ESP_CS) esp32_ready = DigitalInOut(board.ESP_BUSY) esp32_reset = DigitalInOut(board.ESP_RESET)

# If you have an externally connected ESP32: # esp32_cs = DigitalInOut(board.D9) # esp32_ready = DigitalInOut(board.D10) # esp32_reset = DigitalInOut(board.D5)

spi = busio.SPI(board.SCK, board.MOSI, board.MISO) esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset)

print("Connecting to AP...") while not esp.is_connected: try: esp.connect_AP(secrets["ssid"], secrets["password"]) except RuntimeError as e: print("could not connect to AP, retrying: ", e) continue print("Connected to", str(esp.ssid, "utf-8"), "\tRSSI:", esp.rssi)

# Initialize a requests object with a socket and esp32spi interface socket.set_interface(esp) requests.set_socket(socket, esp)

JSON_GET_URL = "http://httpbin.org/get"

# Define a custom header as a dict. headers = {"user-agent": "blinka/1.0.0"}

print("Fetching JSON data from %s..." % JSON_GET_URL) response = requests.get(JSON_GET_URL, headers=headers) print("-" * 60)

json_data = response.json() headers = json_data["headers"] print("Response's Custom User-Agent Header: {0}".format(headers["User-Agent"])) print("-" * 60)

# Read Response's HTTP status code print("Response HTTP Status Code: ", response.status_code) print("-" * 60)

# Close, delete and collect the response data response.close()

WiFi Manager

That simpletest example works but it's a little finicky - you need to constantly check WiFi status and have many loops to manage connections and disconnections. For more advanced uses, we recommend using the WiFiManager object. It will wrap the connection/status/requests loop for you - reconnecting if WiFi drops, resetting the ESP32 if it gets into a bad state, etc.

Here's a more advanced example that shows the WiFi manager and also how to POST data with some extra headers:

# SPDX-FileCopyrightText: 2019 ladyada for Adafruit Industries # SPDX-License-Identifier: MIT

import time import board import busio from digitalio import DigitalInOut import neopixel from adafruit_esp32spi import adafruit_esp32spi from adafruit_esp32spi import adafruit_esp32spi_wifimanager

print("ESP32 SPI webclient test")

# 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

# If you are using a board with pre-defined ESP32 Pins: esp32_cs = DigitalInOut(board.ESP_CS) esp32_ready = DigitalInOut(board.ESP_BUSY) esp32_reset = DigitalInOut(board.ESP_RESET)

# If you have an externally connected ESP32:

# esp32_cs = DigitalInOut(board.D9) # esp32_ready = DigitalInOut(board.D10) # esp32_reset = DigitalInOut(board.D5)

spi = busio.SPI(board.SCK, board.MOSI, board.MISO) esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset) """Use below for Most Boards""" status_light = neopixel.NeoPixel( board.NEOPIXEL, 1, brightness=0.2 ) # Uncomment for Most Boards """Uncomment below for ItsyBitsy M4""" # status_light = dotstar.DotStar(board.APA102_SCK, board.APA102_MOSI, 1, brightness=0.2) # Uncomment below for an externally defined RGB LED # import adafruit_rgbled # from adafruit_esp32spi import PWMOut # RED_LED = PWMOut.PWMOut(esp, 26) # GREEN_LED = PWMOut.PWMOut(esp, 27) # BLUE_LED = PWMOut.PWMOut(esp, 25) # status_light = adafruit_rgbled.RGBLED(RED_LED, BLUE_LED, GREEN_LED) wifi = adafruit_esp32spi_wifimanager.ESPSPI_WiFiManager(esp, secrets, status_light)

counter = 0

while True: try: print("Posting data...", end="") data = counter feed = "test" payload = {"value": data} response = wifi.post( "https://io.adafruit.com/api/v2/" + secrets["aio_username"] + "/feeds/" + feed + "/data", json=payload, headers={"X-AIO-KEY": secrets["aio_key"]}, ) print(response.json()) response.close() counter = counter + 1 print("OK") except (ValueError, RuntimeError) as e: print("Failed to get data, retrying\n", e) wifi.reset() continue response = None time.sleep(15)

You'll note here we use a secrets.py file to manage our SSID info. The wifimanager is given the ESP32 object, secrets and a neopixel for status indication.

Note, you'll need to add a some additional information to your secrets file so that the code can query the Adafruit IO API:

aio_username

aio_key

You can go to your adafruit.io View AIO Key link to get those two values and add them to the secrets file, which will now look something like this:

# 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' : '_your_ssid_', 'password' : '_your_wifi_password_', 'timezone' : "America/Los_Angeles", # http://worldtimeapi.org/timezones 'aio_username' : '_your_aio_username_', 'aio_key' : '_your_aio_key_', }

Next, set up an Adafruit IO feed named test

If you do not know how to set up a feed, follow this page and come back when you've set up a feed

named test . (https://adafru.it/f5k)

We can then have a simple loop for posting data to Adafruit IO without having to deal with connecting or initializing the hardware!

Take a look at your test feed on Adafruit.io and you'll see the value increase each time the CircuitPython board posts data to it!

Code PyPortal NASA Image Viewer

NASA Open API Key

We'll use the NASA API to make our queries and retrieve our image of the day. In order to do so, you'll need to register for a free account with api.nasa.gov and get your API key.

It's easy to do, just head to this link (https://adafru.it/EqP) and enter your name and email address. That's all there is to it! Your API key will be generated and sent to you via email, as well as showing up immediately in the browser. Keep that key (or the email containing it) handy, we'll need to copy and paste it into our code in a moment.

Adafruit IO Time Server

In order to get use the Adafruit image converter, this project will require you to have an Adafruit IO username and key. Adafruit IO is absolutely free to use, but you'll need to log in with your Adafruit account to use it. If you don't already have an Adafruit login, create one here (https://adafru.it/dAQ).

If you haven't used Adafruit IO before, check out this guide for more info (https://adafru.it/Ef8).

Once you have logged into your account, there are two pieces of information you'll need to place in your secrets.py file: Adafruit IO username, and Adafruit IO key. Head to io.adafruit.com (https://adafru.it/fsU) and simply click the View AIO Key link on the left hand side of the Adafruit IO page to get this information.

Then, add them to the secrets.py file like this:

secrets = { 'ssid' : 'your_wifi_ssid', 'password' : 'your_wifi_password', 'aio_username' : 'your_aio_username', 'aio_key' : 'your_big_huge_super_long_aio_key' }

Add CircuitPython Code and Assets

In the Project Code (https://adafru.it/Iua) section further down this page, click on the Download: Project Zip link, and save the .zip archive file to your computer.

Then, uncompress the .zip file, it will unpack to a folder named PyPortal_NASA.

Copy the contents of the PyPortal_NASA directory to your PyPortal's CIRCUITPY drive, and then be sure to rename the nasa.py file to code.py so it will automatically run when the PyPortal restarts.

Editing the Code

You can edit the code.py file with any text editor you like. Adafruit suggests installing the free Mu Python editor as it's super handy, recognizes Adafruit boards, and has a built in serial monitor/REPL to interact with the board. Find out more about Mu here (https://adafru.it/ANO).

Add NASA API Key

Open up code.py in Mu and then copy and paste your API key from NASA that we got earlier in to the

DATA_SOURCE url, getting rid of the words DEMO_KEY and replacing it with your actual API key.

That line will look something like this:

DATA_SOURCE = "https://api.nasa.gov/planetary/apod?api_key=your_actual_really_long_key_here"

When you're done, save the code.py file again to your PyPortal's CIRCUITPY drive.

boot.py

We're using a special file to ensure the .bmp cache writes to the flash properly. This is the unsafe_boot.py file you copied to the drive. Rename it to boot.py now.

Note that you'll see this scary looking text appear during restart, don't worry, it's supposed to say that!

**************** WARNING ******************

Using the filesystem as a write-able cache!

This is risky behavior, backup your files!

**************** WARNING ******************

This is what the final contents of the CIRCUITPY drive will look like:

Project Code

import time import board from adafruit_pyportal import PyPortal

# Set up where we'll be fetching data from DATA_SOURCE = "https://api.nasa.gov/planetary/apod?api_key=DEMO_KEY" # There's a few different places we look for data in the photo of the day IMAGE_LOCATION = ["url"] TITLE_LOCATION = ["title"] DATE_LOCATION = ["date"]

# the current working directory (where this file is) cwd = ("/"+__file__).rsplit('/', 1)[0] pyportal = PyPortal(url=DATA_SOURCE, json_path=(TITLE_LOCATION, DATE_LOCATION), status_neopixel=board.NEOPIXEL, default_bg=cwd+"/nasa_background.bmp", text_font=cwd+"/fonts/Arial-12.bdf", text_position=((5, 220), (5, 200)), text_color=(0xFFFFFF, 0xFFFFFF), text_maxlen=(50, 50), # cut off characters image_json_path=IMAGE_LOCATION, image_resize=(320, 240), image_position=(0, 0))

while True: response = None try: response = pyportal.fetch() print("Response is", response) except RuntimeError as e: print("Some error occured, retrying! -", e)

time.sleep(30*60) # 30 minutes till next check

 If you run into any errors, such as "ImportError: no module named `adafruit_display_text.label`" be sure to update your libraries to the latest release bundle!

How It Works

The NASA Image Viewer is doing a few cool things using CircuitPython and the PyPortal:

Background Splash Screen

First, we'll display a splash screen with the NASA logo. This is a 320x240 pixel RGB 16-bit raster graphic in .bmp format.

Font

We'll be displaying the image title and today's date as text created with a bitmapped font to overlay on top of the background image once that's loaded. The font used here is a bitmap font made from an oblique Arial typeface. You can learn more about converting type in this guide (https://adafru.it/E7E).

JSON

In order to retrieve the NASA Astronomy Picture of the Day (APOD), we'll be making a query to the NASA API.

When you make a request of the APOD server with your API key added, you'll get a JSON file returned as the response.

In fact, you can run the same query as the PyPortal does to see the result. Copy and paste this link

https://api.nasa.gov/planetary/apod?api_key=DEMO_KEY

into your browser, except replace DEMO_KEY with your own API key that NASA sent in the registration email.

When you enter this in your web browser, you'll see a result returned like this:

{ "copyright": "Mario Zauner", "date": "2019-04-03", "explanation": "The famous Horsehead Nebula in Orion is not alone. A deep exposure shows that the dark familiar shaped indentation, visible just below center, is part of a vast complex of absorbing dust and glowing gas. To b ring out details of the Horsehead's pasture, an amateur astronomer used a backyard telescope in Austria to accumu late and artistically combine 7.5 hours of images in the light of Hydrogen (red), Oxygen (green), and Sulfur (blue ). The resulting spectacular picture details an intricate tapestry of gaseous wisps and dust-laden filaments that were created and sculpted over eons by stellar winds and ancient supernovas. The Flame Nebula is visible just to the left of the Horsehead, while the bright star on the upper left is Alnilam, the central star in Orion's Belt. T he Horsehead Nebula lies 1,500 light years distant towards the constellation of Orion. Bounce around the Univer se: Random APOD Generator", "hdurl": "https://apod.nasa.gov/apod/image/1904/HorseheadFlame_Zauner_4404.jpg", "media_type": "image", "service_version": "v1", "title": "Wisps Surrounding the Horsehead Nebula", "url": "https://apod.nasa.gov/apod/image/1904/HorseheadFlame_Zauner_960.jpg" }

That result is a JSON (JavaScript Object Notation) array. It is comprised of a single element with seven key:value pairs. For example, there is one key called date which has a value of 2019-04-03 which is

expressed this way:

"date": "2019-04-03"

And another we care about is the title key, which has a value of Wisps Surrounding the Horsehead Nebula

So that is expressed as:

"title": "Wisps Surrounding the Horsehead Nebula"

Another key we really care about is the url which has a value of the image location:

"url": "https://apod.nasa.gov/apod/image/1904/HorseheadFlame_Zauner_960.jpg"

Since this JSON object array has a consistent way to return the results to us, the code we're running on the PyPortal can easily parse the data and display it!

Here's what the JSON file looks like in the "code beautifier" of Firefox.

You can see how it's done in this part of code.py:

DATA_SOURCE = "https://api.nasa.gov/planetary/apod?api_key=xxxxxxx" #put your api key here IMAGE_LOCATION = ["url"] TITLE_LOCATION = ["title"] DATE_LOCATION = ["date"]

Then, in the pyportal query we ask for the date and title names from that URL, and then use the text_ arguments to set the font , position , color , wrap , and maxlen of the text when it is displayed.

We use the url name to get the path to the .jpeg image file.

pyportal = PyPortal(url=DATA_SOURCE, json_path=(TITLE_LOCATION, DATE_LOCATION), status_neopixel=board.NEOPIXEL, default_bg=cwd+"/nasa_background.bmp", text_font=cwd+"/fonts/Arial-12.bdf", text_position=((5, 220), (5, 200)), text_color=(0xFFFFFF, 0xFFFFFF), text_maxlen=(50, 50), # cut off characters image_json_path=IMAGE_LOCATION, image_resize=(320, 240), image_position=(0, 0))

With all of this prepared, during the main loop of while True: the code will query the NASA page for the JSON data.

When it gets the path of the .jpeg file, the pyportal library passes it along to an Adafruit IO image converter server where the file is converted into the format the PyPortal can display, a 320x240 pixel RGB 16-bit .bmp.

This image is then cached onto the PyPortal's storage and displayed on the PyPortal TFT screen.

Finally, the text will be displayed over the image.

This updates every thirty minutes. Be aware, you cannot make more than 50 queries per day to the NASA API!

 One user reported problems related to a slow internet connection, which they resolved by

increasing the timeout value in the adafruit_requests library from 1 second up to 5 seconds.

Adafruit NASA User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual