Not sure if this is the best place to ask this but I have one of these GEMS displays http://www.gems.co.uk/?content=pages&id=lds4-driver-display I want to run it in my road cars, I will be using it to test some TPMS we supply at work, but I can change pages to display any other info aswell. What I would like to do is display the gear that I'm in but this isnt supplied on the CAN bus so I need to calculate it from speed and rpm I need to know how I can do the calculation as I gone a bit mind F***ed thinking about it to much
