Added "get started" docs including description of the components and steps involved in getting this to work

[justinotherguy]

Hello,

after exploring several routes (that all turned out to be dead-ends atm) for getting back remote access to the SOC (and AC) via CAN-BUS directly I found this project. Love it - absolutely scratches my itches :)

Trying to get this working I noticed the lack of a write-up of the components (what is involved? in which cases do I need what? do I really need that hologram SIM, that is so cheap yet so expensive get get shipped to europe?), how they play together and how I can debug the steps to get this up and running I thought: why not adding this myself? And that's what I did:
https://github.com/justinotherguy/opencarwings/blob/jo_docs_get-started/GET_STARTED.md

So:
a) please gives this a look and tell me what you think. I'd like to get this to a somewhat complete(TM) state and then provide a PR so you can include it in the repo
b) I seem to get stuck at the point of writing the new APN via OBD; as far as I understand the symbol in the CARWINGS menu shows whether the TCU is able to access the internet. The requirements to achieve this:

• have a SIM card installed
• with a contract that allows internet access
• set the APN via OBD
• make sure you're in a region that has coverage for the network of your TCU (2G/3G)
  That should be it, correct?

Out of these I'm unsure about the APN. When I try to write the value (should be "Internet" for my provider), I get a confirmation. When I restart the app to read the value, I do not get an entry back and - depending on the phone I use for this (both of which are able to retrieve the VIN with my OBD dongle) and some other factors that I have not understood so far I do get error messages like "BUFFER FULL" when writing or retrieving the value for "web server".

So - thanks for this project!

Maybe you can help me, I'd like to help improve the project in return :D

Regards, J.

[developerfromjokela]

Hi!

Thanks first of all for the effort!

It's mostly correct, however with the server URL, there are two "servers" in opencarwings.
One is HTTP server for the navigation unit, and then there is a TCP server that communicates directly with the TCU for A/C, charge commands etc.

If you happen to have european TCU model, you'll have correct server address programmed already. Nissan's domain expired few years ago, so I went ahead and purchased it 🤣 and it works perfectly "out of the box". The hostname (no http://, only domain name) for TCU to be set via OBD is: nissan-eu-dcm-biz.viaaq.eu

Navigation unit is programmed separately using this guide: https://opencarwings.viaaq.eu/static/navi_guide.html

I do have a web page guide for TCU also: https://opencarwings.viaaq.eu/static/tcu_guide.html. Maybe worth making a link to this or converting it to markdown & including it in the repo? What do you think?

[justinotherguy]

Yes TCU Activation should be 1

ok, that's correct, so.
We'll see, what the other values show (read/write), once I deactivate the integrity check; I'll keep you posted

[justinotherguy]

ok, deactivating the integrity check does the trick :)
I can now write the settings without error messages and I can confirm the changed values by disconnecting, closing the app and then reading them again.
Alas, the car symbol still remains gray and crossed out.
Guess I'll order a hologram SIM, so.

[developerfromjokela]

ok, deactivating the integrity check does the trick :)

I can now write the settings without error messages and I can confirm the changed values by disconnecting, closing the app and then reading them again.

Alas, the car symbol still remains gray and crossed out.

Guess I'll order a hologram SIM, so.

Make sure you have 2G networks still in your area :) it could be that they are shut down aleeady

[justinotherguy]

thx for the warning! :)
Too late, now, though :D
Seriously: I understand, that 2G is going to be kept alive in Germany until 2028, so I should be fine.

[justinotherguy]

ok, wonderful.
SIM card has arrived (expensive, but lightning fast shipping) (oh - I have ordered 3, b/c the SIM itself is really cheap; just in case someone in the EU reads this - get in touch); inserted, did what the documentation says - worked. Just like that.

I am amazed.

Thank you for this!

Would still like to help improve documentation, especially on getting this to work without the hologram SIM, in case you're interested.