Hi all,
I'm a bit of a computer nerd and I've been wondering how challenging it would be to create a digital dashboard for the Rover 75. (Diesel model)
It's my understanding that the Rover 75 and MG ZT function using 3 main serial bus lines: K-Bus, CAN-Bus and Diagnostic Bus. One of the interesting consequences of using a bus topology is that all the information on the bus can be read by any device connected onto this bus. Using this principle it should be relatively simple to engineer a device that wires itself onto one of the main bus lines of the car and reads the data. This could then be processed and data displayed on a digital dashboard similar to what you see on modern cars.
As for data structure, I would assume that the internal bus systems run on a packet based system where they would have a header and a payload. The header would contain the information such as the originating ECU and intended ECU recipient and the payload would contain whatever data is being transmitted.
So my question would be this: what bus would be the best to try to connect to in order to obtain information such as vehicle speed, engine RPM, trip computer data etc? I would assume this would be CAN-Bus. I would also guess that this information can be found from the diagnostic bus - which would be easier to connect to because of the diagnostic port however I would need to investigate whether the data is always transmitted to the diagnostic port and simply read by the T4 device or if the T4 device sends a request packet to each ECU to gain this information - this would be more challenging as I do not have a T4 to reverse engineer however I could try to reverse engineer TOAF.
As for why I want to do this - I'm bored and think it would be cool, plus I'm dying to know what MPG I'm getting and I don't have that fancy LCD display on my dashboard like the top of the range cars get
