Code only works from Visual Studio



  • I have this code:

    def main():
      purple_air = PurpleAir()
      # Reset orientation when A pushed. End test if testing.
      btnA.wasPressed(purple_air.SetOrientation)
      btnB.wasPressed(purple_air.Testing)
    
      wifi_try_count = 0
      while True:  while True:
        if not (wifiCfg.wlan_sta.isconnected()):
          wifi_try_count += 1
          purple_air.ShowError(
            'No WiFi ({:d})'.format(wifi_try_count))
          wifiCfg.doConnect('FBI', 'CIA')
          purple_air.ShowError('WiFi connected')
        else:
          purple_air.ShowError('Trying')
          try:
            purple_air.GetAQI()
          except Error as e:
            purple_air.ShowError(e)
        purple_air.ShowError('Waiting')
        wait_ms(1)
        purple_air.ShowError('Done')
    

    When I run from Visual Studio, it connects to WiFi, prints WiFi Connected, Waiting, Done, Trying all in a row.

    When I disconnect it, choose it from the App screen, it will stop at WiFi Connected. If I yank out the entire else clause, then it will stop at Waiting. In either case, exactly 1 print statement after connecting to WiFi.

    It's not actually completely dead: Pressing the A or B buttons execute the callbacks as expected.

    But I can't figure out why it reacts differently connected vs. unconnected!

    Any ideas?



  • OK, I have no idea why, but taking out the else: works. (I took out main() first, and that didn't help, but I didn't put it back in once things worked). I haven't run it for a long time, so it might still hang, but initial indications are promising!

    while True:
      if not (wifiCfg.wlan_sta.isconnected()):
        wifi_try_count += 1
        purple_air.ShowError(
          'No WiFi ({:d})'.format(wifi_try_count))
        wifiCfg.doConnect('Mi5', 'double07')
        purple_air.ShowError('WiFi connected')
      try:
        purple_air.GetAQI()
      except Error as e:
        purple_air.ShowError(e)
      wait_ms(1)
    


  • Nope, spoke too soon. It just takes longer to hang. :(



  • I found out that you can actually get a serial console, and it says:

    Traceback (most recent call last):
      File "main.py", line 130, in <module>
      File "main.py", line 128, in <module>
      File "main.py", line 96, in GetAQI
    NameError: name 'wait_ms' isn't defined
    

    Don't ask me why it works when connected to the laptop, though!

    Serves me right for trying to limit the imports. :)


  • M5Stack

    wait_ms is part of the uiflow class, did you import it at the start of your program?



  • I was trying to be "more pythonic" and not import *, i.e.

    from m5stack import lcd
    

    It didn't occur to me that it was in uiflow!
    I've gone back to importing everything. :)



  • I noticed that some development environments use REPL when transferring files and running. And by the way, they silently import various system libraries / modules. Eg uPyCraft imports os library to display a list of files. By the way, the wait_ms () can be imported from the time library



  • Given that I can now see the console, I determined that it throws OSError if the http GET fails. Which is a weird error to throw, but OK. So I put that in my except: clause, and it's humming away!