how to start?

good morning everyone!
I want to start a project for my opel vectra c. i bought an ELM327 and found realdash soft. It was incredible.
I have seen how with the obd2 I read correctly rpm and speed, setting the gear ratio correctly indicates the gear engaged.
I found Adam Varga’s project in which using an arduino and a shield sniffing the can bus and taking out the codes for the actions. in fact I have the CSV with the codes and addresses. I also have the arduino and its MCP2515 CAN module.
my question is … with all the hardware i have, how do i start the project? as I edit the XML for example
simbol door closed, 255,00,00,08,07, AE, 06,01,01,00,08,00 to the format compatible with real dash?

It is difficult to start from scratch and want to face a project like this. I also have another painting of my car that can help me to carry out the project if necessary. Thank you all very much for your help!

You could start with a Seeedstudio CAN adapter so you don’t have to build any custom hardware. Once you get your vehicle CAN mapped with that, you can proceed to build custom hardware for extra sensors etc.

Supported direct CAN adapters listed here:

If its posible, i would use the hardware that i have now. Exist any tutorial to sniff the can bus or what the extensión that i must use to use for hack?

Start with RealDash CAN monitor. That should show you all the information to get started.

Hello, while I learn more about the can-bus I would like to ask a question. What data can be taken from obd2 elm327? for example. turbo pressure, speed, rpm … no problem. with the instantaneous consumption other programs and devices if it reads them directly (or does the calculation with the MAF, etc) RD does not and gives very different values. How can I see the data coming out of the obd2 via bluetooth with the ELM327?

There are some standard PIDs, most listed here:

Unfortunately many manufacturers do not use the standard PIDs but custom, vehicle specific ones. For that reason RealDash cannot read all data from all vehicles automatically.