GPS on a notecard

Hardware
1

Hello,

So i’ve just received my first notecard and i have gone through some of the guides and tutorials but i’m wondering about GPS when set in the periodic mode.

So my understanding it will only send / wake up the GPS on its scheduled wake up if it has detected motion. Is there a way to ALWAYS wake up the GPS for each time interval…
OR if not how can i tell from the JSON on the events thats why it has no NEW GPS data.

Thanks.
John

2

Hi @medida and welcome to the Blues Wireless community!

Personally I would not recommend turning on GPS if it’s not needed, due to battery consumption issues. Alternatively, you can always call the card.location API and if the Notecard hasn’t moved, the response will indicate that the GPS is not active and simply provide the last location, like so:

{
 "status": "GPS inactive {gps-inactive} {gps}",
 "mode": "periodic",
 "lat": 42.5776,
 "lon": -70.87134,
 "time": 1598557149
}
3

Hi

Thanks. In the long term i want it to be as low power as possible- but whilst i’m getting to gri[s with it i want as much information as possible.

At the moment i have set it up as :

{
 "seconds": 240,
 "mode": "periodic"
}

{"req":"card.location.track","start":true,"heartbeat":true,"sync": true,"hours":1}

This is just so i can see data. SO far the tutorials have been great… but testing devices and waiting for minutes / hours is so low… i’m not very patient :rofl:

My understanding is that i will get data at least every hour if the device has not moved.

4

I wouldn’t recommend that config for a battery-powered tracker :slight_smile: but while testing it’s fine. And you’re correct, with heartbeat:true and hours:1 you’ll always get an event at least every hour. Also the sync:true parameter will immediately sync any new tracking data instead of waiting for the next periodic cellular sync (again, good for testing, not great for battery life!).

Also, a little tip if you’re building a tracker without a host MCU. You may want to look into the event data itself to see if you’re gathering GPS location data or not. For instance, with a tracker solution I built, here is an example of an event that was not able to get a GPS fix:

    "body": {
        "status": "heartbeat",
        "temperature": 26.3125,
        "voltage": 4.0976562
    },
    "best_location_type": "tower",
    "best_lat": 3.4645875,
    "best_lon": -76.531921875,
    "best_location": "Cali region",
    "best_country": "CO",
    "best_timezone": "America/Bogota",
    "tower_when": 1635020330,
    "tower_lat": 3.4645875,
    "tower_lon": -76.531921875,
    "tower_country": "CO",
    "tower_location": "Cali region",

…versus when I was able to get a GPS fix:

    "body": {
        "hdop": 2,
        "status": "heartbeat",
        "temperature": 23.5,
        "time": 1637742502,
        "voltage": 3.9726562
    },
    "best_location_type": "gps",
    "best_lat": -15.474297499999999,
    "best_lon": 28.39407421875,
    "best_location": "Lusaka",
    "best_country": "ZM",
    "best_timezone": "Africa/Lusaka",
    "where_olc": "5GPCG9GV+7JP3",
    "where_lat": -15.474297499999999,
    "where_lon": 28.39407421875,
    "where_location": "Lusaka",
    "where_country": "ZM",
    "where_timezone": "Africa/Lusaka",
    "tower_when": 1637936607,
    "tower_lat": -15.468895,
    "tower_lon": 28.388693,
    "tower_country": "ZM",
1 Like
5

Hello.

So my test config drained the batteries quickly - which is not surprising.

In my office its struggling to get a GPS lock - is there a timeout for the GPS , so if it fails after 240 seconds… it just sends the GSM data.

Also is there away to get the config data from the device… i’m made changes / updates and would like to pull the settings from the device so i can review them

Thanks

6

Hi @medida,

It can be difficult to get a GPS lock indoors unless you’re using an external GPS antenna that is more powerful than the one included on our Notecarriers. However, it’s certainly possible if you have a south-facing window. There is a default GPS timeout of 900 seconds.

Most of the Notecard APIs will let you pull the existing config by calling the API without any additional parameters, like card.location.mode for instance.

Rob

7

Thanks.

At the moment i’m just using the onboard items - i have the cardnote sat on a NoteCarrier A

I need to test it out of the box - so i can guage what its base line perfomance is like.

Sadly i’m terribly impatient working with hardware… and waiting for it to connect.
I’m used to just reloading my .net code and running it again

thanks