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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()
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