by GleamingShadow on Wed, 09 Aug 2017 8:38 +0000
I'm sure it is possible, however getting a quality GPS system built into the OEM system would be very difficult. A more likely method of going about this would be by dropping the OEM backend itself and using a custom one. I.e. losing all current functionality of existing system and building another to match it and then support another GPS setup. In theory not difficult to do, just lots of little issues in practice.
One could build a backend running of a Raspberry Pi running Windows IOT Core, build a custom app which takes over all nav, music etc duties then outputting its signal to the display. Of course the most difficult part here would be interfacing the with existing display. One would need to write custom drivers for the Pi based on the exact screens data sheet specs...
You could however do the same as above, however remove the factory screen and replace it with a 3rd party one that will interface with the Pi already. The official one made for the Pi is the same resolution, which isn't great, but it will defiantly work. Otherwise you would have to try find a 7" HDMI display with USB touch functions in a higher resolution package, which could be more difficult. You could also rewire all the existing buttons into the Pi and have them remain functional.
I have been thinking about this for 7 months already. It would be great to have a headunit that does all the usual stuff, plus decent mapping and have things such as OBD functionality built in, or vehicle documentation viewable (workshop manual, oil specs etc etc). It would be relatively simple to get all of that working minus decent mapping, that would be quite a bit more challenging and potentially bordering illegal if you were to reverse engineer Hemas' app for its data then building a new system to work on the data.
Another option would be replacing the screen with an 7" Android tablet. Wouldn't be the simplest headunit, but you could do literally anything Android supports. Whatever music player you want, Hema Explorer, Torque etc.
One could potentially combine a tablet and Pi/arduino together to allow you to rewire the head unit buttons. Buttons -> Arduino, Arduino serial -> tablet. Would need a custom app running on the tablet constantly to poll and interpret serial from the Arduino to then trigger system functions (Volume up/down, music play/pause etc.
be a IT guru out there somewhere who can sort out a fix.
