How to use BME280 sensor with Track mode on notecard AUX pins?

I have been following notecard documentation to work with BME280 sensor and upload weather data to Notehub using Notecard track mode. The documentation has explanation that in track mode, the device uploads data inside _track.qo automatically. But for me it is not working.

The steps I took is following using the browser based cli.

“req”: “card.aux”,
“mode”: “track”
Then do sync.
“req”: “hub.sync”

Unfortunetly the _track.qo file is not uploaded. even if I tried following
{“req”: “card.aux”, “mode”: “track”,“sync”: true,“file”: “_track.qo”}

Hey @ujur007,

You’re correct that running {"req":"card.aux","mode":"track"} tells the Notecard to automatically append temperature, humidity, and pressure to all new Notes it adds to the _track.qo Notefile.

BUT, for the Notecard to use the _track.qo Notefile you must additionally go through the steps to enable tracking. Here is the documentation for doing that: Asset Tracking - Blues Developers. At a minimum you must run the card.location.mode and card.location.track requests.

Thank you for pointing this out because the documentation in the guide you linked to is pretty confusing, so I’m going to work on clarifying that today.


Hi @tjvantoll
Thanks for your reply.
Have you already worked on documentation?
Because, I tried again so that I can include temp, humy, pressure reading from BME280 but it was again not possible. Following the commands you have mentioned and on the link…

For me it would be simple if, I restore the notecard and send some minimum JSON commands to have __track.qo file that has all the data from BME280.

I have wired BME280 as documented on AUX pins. I would like to see __track.qo and if it does not have data from BME280, then maybe sensor is damaged. Though, I have two of them and also tried changing sensor.
anyways take your time…


Hey @ujur007,

The changes are now live Working with the Notecard AUX Pins - Blues Developers.

The main thing I’d recommend though is reading through our guide on asset tracking though, as you must use those requests for the Notecard to add Notes to the _track.qo Notefile Asset Tracking - Blues Developers.

I just tested this myself and was able to get things working with the following requests (and by moving the Notecard around a bit, as you must trigger the accelerometer a bit for tracking by default).

{"req":"card.aux","mode": "track"}

If you’re interested in tracking only temperature, I’d recommend trying out the card.temp request as an alternative to all of this card Requests - API Reference - Blues Developers. That request can also detect and use a BME280 sensor.


Hi @tjvantoll
I tried the same commands you have mentioned before. And I tried it again with moving my Notecard a bit.
It is weird that I did not get _track.qo uploaded to notehub.

BTW, For my project BME280 on AUX pins is not that required but would be nice to have it. I am already using GPS on AUX pins.

Do you see _track.qo Notes when you’re not using {"req":"card.aux","mode": "track"}—aka if you run {"req":"card.aux","mode":"off"}?

Mostly wondering if you had the tracking working before you started to try to get temperature readings.


Hi TJ,

Sorry for late reply.
I am trying to solve the issue. I will get back to you when I am done and find solution