I am trying to figure out how the guide wire sensors work.

There are 4 inputs (digital), P0.7, P0.8, 0.9, P0.10) that the original firmware has put on extint3, two trigger on Falling edge, the other two on Raising edge. Probably and each on each sensor.

There are also two control pins (digital).
One is for Range, or Amplification, P0.21.
If I'm close I get triggers regardless of p0.21 state, and then I am far away from guide wire I only get triggers then P0.21 is High.

The other control pin is so far unknown, P0.22. It changes the output on P0.7-0.10. I cannot figure out how this works yet.

The Falling edge's also show if the mower is looking perpendicular to the guide wire; P0.8, P0.10 is high.
If the mower looks 'Downrange', P0.10 is high, P0.8 low.
If the mower looks 'forward', the opposite, P0.8 High, P0.10 Low.

So, any suggestions? My next move is probobly to try to make a logfile of all the triggers, there are around 10-20 per second.