Radio Packet loss + closed loop control system = lunging robot

[Dave K.]

Originally Posted by Chaychay

Perhaps I am mistaken, but I believe Dave meant that you take the relay output from the RC and wire it back into a digital input on the RC; Setting the relay output so that it is not what the default is.

That way when the problem occurs you can see that the digital input is showing the value of the default relay output, rather than what you set the relay output to be.

(the concept is what I'm trying to clarify, maybe you can use other ports, like digital out to digital in)

Sorry if I have misinterpreted you Dave.

Yes, I was suggesting setting one of the relay outputs true which should drive the pin high.

Though not directly documented, this post from IFI's forum says that the relay outputs are VHCT (logic family) output pins in series with 330 ohm resistors. This should safely drive a "Digital I/O" pin, which just has a 1k series resistor and 0.001uF capacitor to ground before it goes into the CPU's port pin.

The relay and PWM outputs are disabled by the master CPU, but the user Digital I/O pins are untouched, so one of those pins, configured as an output, couldn't be used as an indicator of the robot being disabled.

I added the disclaimer in my inital post that I had tried neither approach yet, and won't be able to do so until tomorrow. I'm reasonably certain that the relay outputs are 5V logic levels but would confirm that first.

I suspect that watching the packet number will work, and if so, I will post an example of how to do that.