So when I load the "real" ArduPlane V2.67 firmware, I get a good
gyro lock, the HUD "arms," and I can calibrate my radio.
But when I load the Sim plane firmware (which is what I need
to use right now), the A/C lights flash wildly, the radio
calibration screen does not recognize my radio, and the
HUD remains "disarmed."
It worked fine for a long while in sim mode, until
one day I tried loading the "real" plane firmware.
Ever since this action, no dice.