this limited the pitch far below the specified target pitch

this avoids a problem where the jump can cause the next command to be
reset to 0

and prevent double read

this allows for the receiver RSSI to be sent over MAVLink

Thanks to Burt Green for the suggestion

thanks to Jon Challinger for the new controllers!

See
http://www.challinger.us/2012/07/16/tuning-arduplane-roll-and-pitch-controllers/
for details