Yeah, I noticed the cabin temp on the MK1 has its own identifier & packet data (0x313, byte #1), which is transmitted by the MK2 but with all zeros. The MK2 reuses the climate control identifier (0x307) and a previously unused byte (#5) in the packet with the exact same data.
Why did Ford do this? Good for business I guess. Mr.FPV gets to sell more MK2 HIMs though, and I guess Ford do too.
Arduinos are just little microcontrollers that have a large software library base and are targeted at hobbyists. The
CAN BUS device I'm using is very dumb, it has buffers for two messages, signals to the Arduino there's something in there waiting, and the Arduino library reads out the identifier and data (always 8 bytes it seems in the FGs).
The library allows me to send in messages too, which is what I'm doing here.. play back various messages to see what happens on the screen.
To get the FGX screen to turn on, I wrote a short program to send every identifier (0x000 to 0xFFF) with 8 bytes of 0xFF data in. 0x433 with the first byte as 0x80 (or less reliably 0x40) was what woke it for me.