Merge pull request #199 from sjefferson99/wifi-improvements

Wifi improvements

enviro/__init__.py

@@ -153,56 +153,105 @@ def stop_activity_led():
 print("    -  --  ---- -----=--==--===  hey enviro, let's go!  ===--==--=----- ----  --  -     ")
 print("")
 
+def reconnect_wifi(ssid, password, country):
+  import time
+  import network
+  import math
+  import rp2
+  import ubinascii
+
+  start_ms = time.ticks_ms()
+
+  # Set country
+  rp2.country(country)
+
+  # Reference: https://datasheets.raspberrypi.com/picow/connecting-to-the-internet-with-pico-w.pdf
+  CYW43_LINK_DOWN = 0
+  CYW43_LINK_JOIN = 1
+  CYW43_LINK_NOIP = 2
+  CYW43_LINK_UP = 3
+  CYW43_LINK_FAIL = -1
+  CYW43_LINK_NONET = -2
+  CYW43_LINK_BADAUTH = -3
+
+  status_names = {
+    CYW43_LINK_DOWN: "Link is down",
+    CYW43_LINK_JOIN: "Connected to wifi",
+    CYW43_LINK_NOIP: "Connected to wifi, but no IP address",
+    CYW43_LINK_UP: "Connect to wifi with an IP address",
+    CYW43_LINK_FAIL: "Connection failed",
+    CYW43_LINK_NONET: "No matching SSID found (could be out of range, or down)",
+    CYW43_LINK_BADAUTH: "Authenticatation failure",
+  }
 
-import network # TODO this was removed from 0.0.8
-def connect_to_wifi():
-  """ TODO what it was changed to
-  if phew.is_connected_to_wifi():
-    logging.info(f"> already connected to wifi")
-    return True
-  """
-
-  wifi_ssid = config.wifi_ssid
-  wifi_password = config.wifi_password
-
-  logging.info(f"> connecting to wifi network '{wifi_ssid}'")
-  """ TODO what it was changed to
-  ip = phew.connect_to_wifi(wifi_ssid, wifi_password, timeout_seconds=30)
+  wlan = network.WLAN(network.STA_IF)
 
-  if not ip:
-    logging.error(f"! failed to connect to wireless network {wifi_ssid}")
+  def dump_status():
+    status = wlan.status()
+    logging.info(f"> active: {1 if wlan.active() else 0}, status: {status} ({status_names[status]})")
+    return status
+
+  # Return True on expected status, exception on error status (negative) and False on timeout
+  def wait_status(expected_status, *, timeout=10, tick_sleep=0.5):
+    for i in range(math.ceil(timeout / tick_sleep)):
+      time.sleep(tick_sleep)
+      status = dump_status()
+      if status == expected_status:
+        return True
+      if status < 0:
+        raise Exception(status_names[status])
     return False
 
-  logging.info("  - ip address: ", ip)
-  """
-  import rp2
-  rp2.country("GB") 
-  wlan = network.WLAN(network.STA_IF)
   wlan.active(True)
-  wlan.connect(wifi_ssid, wifi_password)
+  # Disable power saving mode if on USB power
+  if vbus_present:
+    wlan.config(pm=0xa11140)
 
-  start = time.ticks_ms()
-  while time.ticks_diff(time.ticks_ms(), start) < 30000:
-    if wlan.status() < 0 or wlan.status() >= 3:
-      break
-    time.sleep(0.5)
+  # Print MAC
+  mac = ubinascii.hexlify(wlan.config('mac'),':').decode()
+  logging.info("> MAC: " + mac)
+
+  # Disconnect when necessary
+  status = dump_status()
+  if status >= CYW43_LINK_JOIN and status < CYW43_LINK_UP:
+    logging.info("> Disconnecting...")
+    wlan.disconnect()
+    try:
+      wait_status(CYW43_LINK_DOWN)
+    except Exception as x:
+      raise Exception(f"Failed to disconnect: {x}")
+  logging.info("> Ready for connection!")
+
+  # Connect to our AP
+  logging.info(f"> Connecting to SSID {ssid} (password: {password})...")
+  wlan.connect(ssid, password)
+  try:
+    wait_status(CYW43_LINK_UP)
+  except Exception as x:
+    raise Exception(f"Failed to connect to SSID {ssid} (password: {password}): {x}")
+  logging.info("> Connected successfully!")
 
-  seconds_to_connect = int(time.ticks_diff(time.ticks_ms(), start) / 1000)
+  ip, subnet, gateway, dns = wlan.ifconfig()
+  logging.info(f"> IP: {ip}, Subnet: {subnet}, Gateway: {gateway}, DNS: {dns}")
+
+  elapsed_ms = time.ticks_ms() - start_ms
+  logging.info(f"> Elapsed: {elapsed_ms}ms")
+  return elapsed_ms
 
-  if wlan.status() != 3:
-    logging.error(f"! failed to connect to wireless network {wifi_ssid}")
+def connect_to_wifi():
+  try:
+    logging.info(f"> connecting to wifi network '{config.wifi_ssid}'")
+    elapsed_ms = reconnect_wifi(config.wifi_ssid, config.wifi_password, config.wifi_country)
+    # a slow connection time will drain the battery faster and may
+    # indicate a poor quality connection
+    seconds_to_connect = elapsed_ms / 1000
+    if seconds_to_connect > 5:
+      logging.warn("  - took", seconds_to_connect, "seconds to connect to wifi")
+    return True
+  except Exception as x:
+    logging.error(f"! {x}")
     return False
 
-  # a slow connection time will drain the battery faster and may
-  # indicate a poor quality connection
-  if seconds_to_connect > 5:
-    logging.warn("  - took", seconds_to_connect, "seconds to connect to wifi")
-
-  ip_address = wlan.ifconfig()[0]
-  logging.info("  - ip address: ", ip_address)
-
-  return True
-
 # log the error, blink the warning led, and go back to sleep
 def halt(message):
   logging.error(message)
@@ -464,6 +513,15 @@ def upload_readings():
     logging.error(f"! cannot find destination {destination}")
     return False
 
+  finally:
+    # Disconnect wifi
+    import network
+    logging.info("> Disconnecting wireless after upload")
+    wlan = network.WLAN(network.STA_IF)
+    wlan.active(True)
+    wlan.disconnect()
+    wlan.active(False)
+
   return True
 
 def startup():

enviro/config_defaults.py

@@ -18,6 +18,11 @@ def add_missing_config_settings():
     warn_missing_config_setting("usb_power_temperature_offset")
     config.usb_power_temperature_offset = DEFAULT_USB_POWER_TEMPERATURE_OFFSET
 
+  try:
+    config.wifi_country
+  except AttributeError:
+    warn_missing_config_setting("wifi_country")
+    config.wifi_country = "GB"
 
 def warn_missing_config_setting(setting):
     logging.warn(f"> config setting '{setting}' missing, please add it to config.py")

enviro/config_template.py

@@ -11,6 +11,7 @@
 # network access details
 wifi_ssid = None
 wifi_password = None
+wifi_country = "GB"
 
 # how often to wake up and take a reading (in minutes)
 reading_frequency = 15