Networking with MicroPython

Connect to wifi 

from WIFI import WIFI

networks = (("SCWiFi","wifi1234"),) # Wifi network and password
wifi = WIFI(networks)
ip = wifi.connect()                # Connect to the wifi network
wifi.ntptime()                     # Fetch current time

Get current date/time

  • Requires an active Internet connection over wifi (as per above)
import time
from WIFI import WIFI

# Connect to Wifi and fetch the current time
networks = (("SCWiFi","wifi1234"),) # Wifi network and password
wifi = WIFI(networks)
ip = wifi.connect()                # Connect to the wifi network
wifi.ntptime()                     # Fetch current time

# Get the current time as a tuple variable
# Format: (Year, Month, Day, Hour, Minute, Second, Weekday, Day_of_Year)
now = time.localtime()

# We can pick out specific pieces of time using their index! (Count from 0)
# Index [3] is the Hour (in 24-hour format: 0 to 23)
# Index [4] is the Minute (0 to 59)
# Index [5] is the Second (0 to 59)
current_hour = now[3]  
current_minute = now[4] 
print("The time is", current_hour, ":", current_minute)

Example using a NeoPixel as an alarm clock

import time
import machine
import neopixel
from WIFI import WIFI

# Connect to Wifi and fetch the current time
networks = (("SCWiFi","wifi1234"),) # Wifi network and password
wifi = WIFI(networks)
ip = wifi.connect()                # Connect to the wifi network
wifi.ntptime()                     # Fetch current time

# Setup the NeoPixel 
led = neopixel.NeoPixel(machine.Pin(48), 1)

while True:
    # Read the clock
    now = time.localtime()
    hour = now[3]
    minute = now[4]
    
    # Check if it's 14:30 (2:30 PM in 24-hour time)
    if hour == 14 and minute == 30:
        print("Time's up! Flashing the light!")
        
        # Flash Blue
        led[0] = (0, 0, 255)
        led.write()
        time.sleep(0.5) # Wait half a second
        
        # Turn Off
        led[0] = (0, 0, 0)
        led.write()
        time.sleep(0.5)        
    else:
        # If it's not the right time, print a status and sleep
        print("Waiting... Current time ->", hour, ":", minute)        
        # Wait 10 seconds before checking the clock again
        time.sleep(10)

Asking for Information (eg, Dad joke) 

import requests # Use 'urequests' if running on ESP32
import json
from WIFI import WIFI

# Connect to Wifi and fetch the current time
networks = (("SCWiFi","wifi1234"),) # Wifi network and password
wifi = WIFI(networks)
ip = wifi.connect()                # Connect to the wifi network
wifi.ntptime()                     # Fetch current time

# Fetch data from a web URL
response = requests.get("https://icanhazdadjoke.com/", headers={"Accept": "application/json"})

# Check if it worked (200 means OK!)
print(response.status_code) 

# Show me the joke
data = ujson.loads(response.text)
print(data["joke"])

Asking for Information (eg, Weather) 

import requests # Use 'urequests' if running on ESP32
import json
from WIFI import WIFI

# Connect to Wifi and fetch the current time
networks = (("SCWiFi","wifi1234")) # Wifi network and password
wifi = WIFI(networks)
ip = wifi.connect()                # Connect to the wifi network
wifi.ntptime()                     # Fetch current time

# Documentation is at
# https://data.gov.hk/en-data/dataset/hk-hko-rss-current-weather-report
url = "https://data.weather.gov.hk/weatherAPI/opendata/weather.php?dataType=rhrread&lang=en"
response = requests.get(url, headers={"Accept": "application/json"})


if response.status_code == 200:
    # Extract the info we want from the data returned.
    # To solve this requires studying the documentation from 
    # the API provider (in this case HKO)
    data = json.loads(response.text)
    rainfall = data['rainfall']['data'][6]['max'] # Sha Tin district
    temperature = data['temperature']['data'][6]['value'] # Sha Tin district
    humidity = data['humidity']['data'][0]['value'] # HK region


    print("Rainfall the past hour: ",rainfall,"mm")
    print("Current temperature: ",temperature,"°C")
    print("Humidity: ",humidity,"%")

Send a message via ntfy 

import requests # use urequests for micropython

requests.post("https://ntfy.sh/your-channel-id", data="This is your message")

ESP NOW

ESP NOW is a wireless protocol specifically for ESP devices to create a mesh network.

import machine
import time
import stc
import espnow

# Button
button = machine.Pin(4, machine.Pin.IN, machine.Pin.PULL_DOWN)

# Setup ESPNow
e = espnow.ESPNow()
e.active(True)
peer = b'\xff\xff\xff\xff\xff\xff' # Broadcast address
e.add_peer(peer) # Add as peers any devices you wish to transmit to

# Let's go
points = Points()
while True:
    sender, msg = e.irecv(200)
    if msg:
        print(f"Message received from {sender}: {msg}")
    if button.value():
        print("Broadcasting hello")
        e.send(peer, 'Hello'.encode('utf-8'))
    time.sleep(0.2)

Note: To convert a MAC address string like “AB:12:34:CD:56:78” into the format required by the espnow.ESPNow.add_peer() method, which requires a bytes object, you can follow these steps:

mac = "AB:12:34:CD:56:78"
peer = bytes(int(part, 16) for part in mac.split(':'))
print(peer)  # Output: b'\xab\x12\x34\xcd\x56\x78'

Copyright © Paul Baumgarten.