I will try you help with researching CAN protocol and share my experience
1.) Im using USBCAN device which have 2 wire connection or CAN network. Device new cost around 100€ What is little more than ELM327 device(Not cheap chinese toy)...
2.)For logging Im use CANHacker application which have Monitor mode from which you can easy monitor data and se what thing change what without searching trough all lines...
3.)Im make my own CAN plugin for Centrafuse and must say that is prety simple to do it Much easier than my GPS engine plugin You just open serial port send 2-3 commands(clear FIFO, setup CAN speed and open can network) and you see data which come to COMPort. Data are in next format:
For example from last t281 we can see:
where next xx things for my car mean:
engine water temp. offset -40 degrees from -40 to 215 degrees:
3E(HEX)=62(DEC) temp= 22°C
fuel consumption factor 0.0022 from 0 to 132 L / hour
car turned off so there has not be any consumption
engine speed (rpm) factor = 32 0 to 8000 rpm
car turned off...
And there is a lot of researching... A lot of CAN codes for my car Im find on web so this has been a lot of easier...