Photon Crashing After Several Variable calls

Firmware
1

HI

I am writing a web app and am using Javascript setinterval to repeatedly request variable values. This was fine with one variable, but once i started requesting 3 my photon crashed (solid cyan LED). I am guessing it can’t cope with 3 requests very close together? Does this seem a likely cause?
If it is, I guess I can create a JSON string with my 3 variables and then extract in my JS, or stagger the requests.

Thanks

2

Solid Cyan LED is not a sign of the Photon crashing. If you want some help then maybe posting your code? Are you using SYSTEM_THREAD(ENABLED); show the registration of the Particle Function and the Function handler.

Do you wait for the return code before sending the next command/function API call?

1 Like
3

Apologies for not replying sooner. Been bogged down homeschooling my children.
Code is here:
https://go.particle.io/shared_apps/5ee48f97fbd3d5000c75e40e
The javascript is sending API calls in very quick succession with no delay between, I think this was this issue. Going forward I am going to try to do the API calls from PHP to hide the access token from the client, so this post can probably be closed now?

Thanks for your help.

4

A few things to note

  • you are using deprecated syntax for exposing your variables, you would now merely write Particle.variable("temperature", temperatureInC)
  • you should register Particle.variables() as early as possible in setup()
  • you should not use such long delay()s but rather opt for a non-blocking approach
  • try to avoid String and rather use C-strings (aka char array)
  • all your Particle.publish() calls should be scoped PRIVATE
  • make sure that none of your divisions ever divide by zero
  • you should not publicly post access tokens or API keys

Solid cyan indicates a deadlock (often between system and user application firmware) when both try to access a shared resource (e.g. a HW interface).

5

Thanks. I shall take all those points on board and try to improve the code. My C isn’t great so need to do a bit of learning.

6

I have incorporated most of the suggestions above into this revision
https://go.particle.io/shared_apps/5ee4c389fbd3d5001775e5f6

7

Thanks for doing that. Is the delay method you used better than using the elapseMillis library or is it doing much the same thing?

8

It’s doing pretty much the same thing without the need for a “library” - you can’t really get a lot shorter than this three-liner.

If you have a look at the implementation of the elapsedMillis “library” you’ll see there would merely be some extra definitions you won’t be using after all :wink:

1 Like
9

Thanks Again

10

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