The problem is I am not using a car PC but the stock RNS510 which is a close system. I doubt if it supports custom data display of any kind.
How do you grab data from can bus with Arduino? Use MCP2551 and MCP2515?
Oh OK, yeah I don't think you can modify the 510 to send extra data. Maybe with vagcom perhaps but I don't know. I totally pulled my RNS2 from the car since the carpc replaced it. Yes with the arduino I'm using mcp2215/2251's. I originally brought a spark fun CANBUS shield then after looking at the schematic I built another one without the GPS, LCD and joystick to connect with my teensyduino.
You can do that, all you need is 2 CANBUS devices. One to receive/transmit to the RNS and another to receive/transmit to the infotainment/convience bus. Then program the arduino to move msgs back and forth across them. There's a company who has boost and other information that they show on the MFD and that's exactly how they do it. I've found that you don't have to register on the bus to send info if you are mimicking something already on the bus...say the RNS. It comes down to what you want to put in the display and from where.
As far as I have seen, RNS does not display any vehicle data like RPM or coolant temperatures. That means the software running on it is not progammed to display those data. Even if I hack into the can bus, without replacing or injecting software in RNS, how will it display the data I want it to display?
You send the characters and the graphics you want do display directly. It doesn't have built in graphics, it shows the dynamic graphics coming in over the CAN bus.
Do you have a version of this that uses the newer/better STN1110 ?
Would love to have one of these that is set to plug into a board... I don't need the actual connector since I plan to splice mine into the line to allow the connector to stay in place. Since the dash cluster uses ODB II I may just tie into the dash feed and not need the normal connector at all.
The STN1110 has a much faster refresh rate and is supposed to be much more compatible than the ELM327 chip.