My APM and MP communicate fine through MP and 3dr radios, can load settings, wps, get telemetry, etc... but when I try and update the APM ardupilot firmware it fails connection after "reading hex". I have searched and read other posts for hours with no success. No other ports are open on my pc when trying to update firmware, etc...... My configuration is listed below. PLEASE help!
upgrading to Arduplane 3.0.3 from ??? a year or more old version.
Firmware connection failure after "reading hex"