How to "hack" a IoT GPS tracker to gather more system data?

[Tomthumb62]

I recently posted about a cheap way to monitor system voltage using a GPS tracker: https://diysolarforum.com/threads/cheap-way-to-“monitor”-remotely.65084/#post-814774

We already had the tracker and the fact it shows system voltage is a bonus.

Then I thought, since the tracker can read and send system voltage to a mobile app on my phone, what if I could feed it other information, such as data from the SCC (Renogy Rover 30A, could add a bluetooth, Victron bluetooth charger and Victron inverter with bluetooth) and the tracker could send that data over the cellular network.

I realize this would require some custom programming and some of this data may be locked behind proprietary doors (I imagine especially with Victron), but thought it would be worth asking the question. Getting the data out would be one thing, but then getting the GPS tracker to take it (and pass it along through a data connection) would be a whole other thing.

Anyone done anything like this? I have little programming experience beyond some HTML/CSS (editing mostly not writing from scratch) and BASIC from many years ago. The needle in the haystack would be someone has already created such a solution and it's open-source...

 

[octal_ip]

The GV75MG you linked to does have a UART port, which according to the marketing material can support various external data sources like a CAN bus module and RFID reader. That being said, there's no information around how the device can be programmed or customized to interface with other proprietary devices with thier own interface types and protocols. Even if there was a readily available development environment for this purpose, it would be no small task to write the logic to encode/decode the various protocols used by your other hardware.

There's plenty of Arduino based projects that retrieve data from various BMS/SCCs/inverters. I've written a few from scratch myself. Adding a 4G/LTE module to to the Arduino device to transmit data would be the best option, as I feel fudging it through the GPS tracker would be far more difficult than using well established and existing solutions.

 

[Tomthumb62]

The GV75MG you linked to does have a UART port, which according to the marketing material can support various external data sources like a CAN bus module and RFID reader. That being said, there's no information around how the device can be programmed or customized to interface with other proprietary devices with thier own interface types and protocols. Even if there was a readily available development environment for this purpose, it would be no small task to write the logic to encode/decode the various protocols used by your other hardware.

There's plenty of Arduino based projects that retrieve data from various BMS/SCCs/inverters. I've written a few from scratch myself. Adding a 4G/LTE module to to the Arduino device to transmit data would be the best option, as I feel fudging it through the GPS tracker would be far more difficult than using well established and existing solutions.

That's about what I thought. Appreciate the reply, though. Was wishful thinking that it would be easier than that. Would take me a year or two to learn the skills (at least) to try to tackle even the Arduino thing. My BMS is likely proprietary and so it's data is probably locked up somehow. When I first bought the battery, I tried like a dozen BMS apps. Nearly all but the two official ones couldn't even recognize the battery. A couple apps did recognize it, but couldn't connect or retrieve data. I might write the folks who make the GPS tracker if they have any more info on how to use the UART port. There are a ton of wires on the wiring harness that aren't being used for anything, so some of those must be for that.