APM2s Possibly Bricked

Hey all, so I have a pair of APM2s that aren't working and I can't figure out why or how to fix them. I'll call them Alpha and Beta.

Alpha will seemingly function when connected to a battery: lights flash, GPS locks, RTF light comes on, etc.  However, neither the USB nor the telemetry port work completely.  The telemetry powers the radio but doesn't send or accept traffic, but that's not as important as USB.  When I connect the USB, the APM powers up, the computer recognizes it as an APM, and I have the option of connecting to it in APM Planner. If I try, it says Getting Params as usual, and the Tx light flashes but not as much as my other APMs. After about 7 seconds it flashes a lot faster and the Planner says Timeout on read: Your serial link isn't fast enough.  The Tx light then becomes solid on and stays that way even if you reset.  If I connect in the terminal, all of the usual "GROUND START...Demo Servos!...Warming up ADC...Demo Servos!... Ready to FLY" shows up fine, so clearly the baud rate is in fact correct. I wrote a python MAVLink dissector, and all of the packets the APM is sending are completely correct.  So basically with Alpha it comes down to everything is working perfectly, all my tests are showing that it's working and sending legitimate data, but the telemetry port isn't working and Planner can't successfully connect. I have used multiple USB cables and computers. Any thoughts?

Beta also does the correct boot sequence with the LEDs, but again the telemetry port and USB port do not work, this time at all.  When I attempt to connect with the Planner, the Rx light flashes once as it should, but the APM never transmits, same with the terminal.  So basically with Beta, it won't communicate at all and there's nothing I can really think of to test with.  As much as I love my APM1s, I'd like to not have to go back to using them because these 2s are broken, and I haven't even done anything out of the ordinary with them.  Any help would be appreciated.

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  • One time my apm2 was bricked. It begin the initialization and then freeze. To solve this issues I do the following:

    In arducopter code, function init_ardupilot (file sytem.pde), just after the Serial port initialization "Serial.begin(SERIAL0_BAUD, 128, 256);"
    I add the following instruction
    which force the start of the cli before all others initializations. I compile and sent it to the apm. Then connect with serial usb, erase the eeprom and does a reset with cli command.

    After this I resent the correct code to the apm, reconfigure it and everything where working fine.

    It would be cool, if in next version of "mission planner" there is a possibility to send a small program that clean everything and in particular the eeprom.

  • 3D Robotics

    With Alpha, have you tried reloading the firmware and erasing the eeprom (CLI setup/erase)?

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