'Cannot communicate' after rest call

[MarkJames]

I'm finishing up a personal webpage for lighting control that uses the rest interface to turn lights on and off.

 

It works fine but I've noticed that once in a while after the rest calls to turn on a light I'll get a 'cannot communicate with <light I just switched>' error from ISY admin console related to the light that I just controlled or polled via the rest interface.

 

It doesn't matter, really, and if the admin console is closed then I wouldn't even know it.  I'm just curious if there's something quirky that I'm doing with my rest calls or if this is just normal behavior when controls and queries come from the rest interface..

 

Thanks,

 

mark

Edited June 25, 2016 by MarkJames

[mwester]

No, this is not normal behavior -- this usually indicates communication problems between the ISY's PLM and the device in question.  The REST API call cannot cause this -- HOW the "On" or "off" event is triggered is immaterial to the on-the-electrical-wire signal.

 

However, if you really only ever see this with the REST calls, it could indicate that perhaps your REST call is doing something different from what you're doing when you turn that device on or off from the Admin console -- for example, perhaps you're addressing the device from the Admin console, but turning on or off a *scene*, and perhaps that scene references some non-existent device, thus triggering the error.  Or perhaps (and this is a stretch) your computer from which you generate the rest call is creating electrical noise on the powerline, and its just a coincidence that the program you're running creates exactly right sort of load on the computer to create the right sort of noise so that interference is generated when you issue the REST call... (I said it was a stretch!  You're better off investigating a common ordinary generic interference issue instead!)

[MarkJames]

No, this is not normal behavior -- this usually indicates communication problems between the ISY's PLM and the device in question.  The REST API call cannot cause this -- HOW the "On" or "off" event is triggered is immaterial to the on-the-electrical-wire signal.

 

However, if you really only ever see this with the REST calls, it could indicate that perhaps your REST call is doing something different from what you're doing when you turn that device on or off from the Admin console -- for example, perhaps you're addressing the device from the Admin console, but turning on or off a *scene*, and perhaps that scene references some non-existent device, thus triggering the error.  Or perhaps (and this is a stretch) your computer from which you generate the rest call is creating electrical noise on the powerline, and its just a coincidence that the program you're running creates exactly right sort of load on the computer to create the right sort of noise so that interference is generated when you issue the REST call... (I said it was a stretch!  You're better off investigating a common ordinary generic interference issue instead!)

 

Definitely not a scene - just single devices.  I'm just getting around to coding my site for scenes so I know there's none in there.

 

I was thinking it might be a timing issue or collision issue between the REST interface and the 'regular' communication.... asynchronous stuff can be funny that way.  I suspect ISY internally regulates it's communication to prevent collisions but has no way of knowing when I come along and throw a REST call into the mix

 

mark

Edited June 25, 2016 by MarkJames

[Michel Kohanim]

Hi Mark,

 

Those are communication issues at INSTEON level. I bet that you will have the same problem were you to turn them on/off from Admin Console as well.

 

With kind regards,

Michel