TABS nodes from Tracknet (now Semtech)

pragmasoft · February 24, 2021, 8:53pm

Just wondering if someone here uses TBOL100 Browan Object Locator devices.

I try one to track a moving object, and while TBOL100 does what I expect it to do - start sending locations every 2 minutes, when moves - it does always send GNSS fix that has been 2-3-4 minutes ago. So while roundtrip time from the sensor via my own gateway, then through TTN to HTTP hook of my service, then to the app is 1-2 seconds, position reflected in the app is 2-4 minutes from the past.
This kind of defies the purpose of real-time object tracking, and the end device is the culprit.

I wonder whether this is by design, or there is some parameters in TBOL100 I can tune? This doesn’t seem logical, other sensors do send realtime fixes but this is the lightest one and hence preferable. Firmware upgrade?

bertrik · February 24, 2021, 9:37pm

There are a couple of downlink commands you can send to tune the behaviour, see the manual at (for example), from page 12 on:

pragmasoft · February 25, 2021, 10:01am

Well, I did send 00 1E 00 on port 204, as described in manual, but it doesn’t seem to have any effect on the device.
Now it still sends every 2 minutes and 30 seconds.

bertrik · February 25, 2021, 12:32pm

I believe the commands have to be sent as confirmed downlink messages. I’ve seen a TBMS100 respond with a configuration settings uplink message each time a configuration command was sent. Do you also see that?
If it isn’t working for you, I think you should contact the manufacturer.

pragmasoft · February 25, 2021, 12:44pm

I tried with confirmed too, same effect. And yes I’ve written to BroWAN, no response yet…
The problem is not in the frequency of the updates as such, the problem is that each update comes with a fix (real position) that has been 2-4 minutes ago - as seen visually and on another trackers.

I wonder if there are any other similar devices, LoRaWAN GNSS and <50 g weight… that one fits my case quite good, be it not for real-time fixes…

mid-walesha · February 28, 2021, 7:31pm

two weeks and still lost my MCF88

pragmasoft · March 10, 2021, 10:23am

Got response from Browan, even had a call with them. Seems like the sensor I bought was older version that just didn’t have all these features. Ordered two new tabs, works like a charm.

pragmasoft · March 14, 2021, 11:50am

Documented my journey with BroWAN nodes.

Server-side + frontend app (Scala + TypeScript):

TTN Decoder function working with latest TBOL100

github.com

jacum/catracker/blob/main/ttn-decoders/tabs.js

function Decoder(bytes, port) {
    var params = {
        "bytes": bytes
    };

    bytes = bytes.slice(bytes.length-11);

      if ((bytes[0] & 0x8) === 0) {
        params.gnss_fix = true;
      } else {
        params.gnss_fix = false;
      }

      // Mask off enf of temp byte, RFU
      temp = bytes[2] & 0x7f;

      acc = bytes[10] >> 5;
      acc = Math.pow(2, parseInt(acc) + 2);

      // Mask off end of accuracy byte, so lon doesn't get affected

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ownergalileo · May 11, 2022, 9:30am

Hi,

i used your uplink payload formatter on TTN for the Browan Object Locator but i am not getting correct location information.
I am using the Browan Object Locator.
I don’t understand where is the error in the code? Looking at the manual I believe the code is correct.

descartes · May 11, 2022, 10:30am

Please do not double post - which thread should the volunteers answer - it will split the responses and it may never come to a conclusion.