How to link Arduino Uno and ThingWorx by using REST API?

[jliu1]

Hi all. I'm doing the Weather App with Arduino Uno tutorial now but stuck with a weird problem. I followed all the instructions in the step1 of How to create the mashup for the Arduino Uno,  but didn't got the expected result. The gauge and the LED display should get data from the Arduino Uno and change after clicking the "Viewmashup", but they did't. I've checked the Arduino Uno that worked properly, it could send data successfully. And I also checked my setTempAndHumid service and AppKey, it could also work with no error. Is there anyone can help me out? Thanks a lot!

[jwyatt]

I haven't personally been through that tutorial / guided-experience, but (just off the top of my head) have you confirmed that something is actually triggering your "setTempAndHumid" service?

When you access this Service in the Mashup Editor via the green "+" symbol on the top-right, it can be quite easy to miss checking the "Mashup Loaded" box. If you don't later tie the Mashup's "Loaded" Event to the Service, then it never gets called, and it seems like nothing is working (because no logic is running).

You can quickly check this by highlighting the "setTempAndHumid" Service in the Mashup Editor. When you do so, the connections to and from that Service will show up in your Connections window in the bottom-center. You'll almost certainly see the connections from this Service to your various Widgets (since you describe connecting them in your original post), but also confirm that something is leading *to* that Service from the left side.

Once again, I haven't been through that guided-experience, so it may not be getting triggered via the Mashup -> Loaded Event. There may be some other mechanism. But there should be *something* triggering it.

Thank you.

Jason

[jliu1]

Hi Jason

Thanks a lot for your advice.

Is the Mashup Editor you mean the mashup in edit mode? I tried to find the "setTempAndHumid" Service in the mashup under edit mode, but i couldn't find it....

However, I remembered I checked the "Mashup Loaded" box for the Service "GetProperties", not the "setTempAndHumid". The "setTempAndHUmid" is a service that I created under "HTU21Dthing", the " GetProperties" is the default service that I added for the mashup to retrieve data.

I'm just a very beginner of ThingWorx and from my point of view that the "setTempAndHumid" Service only connects with the "HTU21Dthing". I cannot see any connections between the "setTempAndHumid" Service and the mashup......

Please give me more suggestions about this problem.

Thank you so much!

Jimeng

[jwyatt]

Jimeng,

Apologies. I had originally thought that you were referring to one of the DevZone "Devices" guided-experiences at this address:

Device QuickStart Kits  | ThingWorx

But it appears that you're probably here:

Weather App with Arduino Uno | ThingWorx

Can you confirm?

I'll try and look through the instructions to see if I can get an idea where something might have gone off the rails. Unfortunately, I can't directly replicate it as I don't have an Arduino myself... but maybe I'll see something for some more suggestions for you.

In the meantime, if you haven't been through the general Tour from the DevZone's homepage, that may be helpful:

ThingWorx Developer Zone | ThingWorx

Thanks.

Jason

[jliu1]

Hi Jason

Thanks so much for your suggestions!

I have already solved my problems by finding that I mistakenly added ONE space before the whole series Appkey......

Anyway, really thanks a lot for your help!!!

Best Regards

Jimeng

[jwyatt]

Jimeng,

Glad to hear it ended up being something innocuous!

Good luck with your future endeavors.

Jason