Hi there all.
(This problem is on APM1 2560)
2 days ago I was merrily aduplaning around doing some PID tuning and all was well. Brought the aircraft in for a smooth landing and called it quits for the day. The very next day went for a drive down south to do some more tuning, fired up the telemetry and noticed No GPS lock on the planner screen. No dramas i thought... i'll just check the light on the gps(mediatek)... it was solid. Weird. So I tried every reset type and still no joy. Still a solid light on the gps but no fix on the planner. Called it quits for the day and just did some manual flight. Came home and decided to connect via USB. More problems.. now I can connect via USB only as the ardupilot is rebooting/initialising. If I wait till eveything initialises i can no longer connect. I get the message serial link isn't fast enough. (please see the attached picture). What makes it even more weird is that if I swap back to Ublox I can connect whenever I want (booting or well initialised) and get a gps fix within 2 mins (whilst sitting by the window). To make things even more confusing..... when using the Ublox the HUD is pitching up and down slightly +/- 10°. Talk about a frustrating couple of days!
Any ideas anyone... maybe a troubleshooting method? By brain hurts!
Replies
Are you using the MTK GPS? I've has a problem with that module when connecting it to an Arduino. The second I switch it on, solid light rather than flashing. Seems to be something linked to the state of the serial lines when it boots. My solution has been turn everything on, if I get a solid light straight away, unplug the GPS only for a second or two then reconnect. Then it works fine.
Sounds like a serial port problem. Can you fire up the Arduino IDE can capture some of the output from the COM port for the APM?