Newbie challanges with 3dr radios

This s my first setup with apm2 and 3dr 900 MHz radios.I am in the testing and setup phase and the radio link disconnects randomly every 2-6 min. Some times the green lights starts blinking indicating the radio link is lost, most of the timeout stays green (or reconnects fast enough so I do not see it blinking) . Once green again I need to "re"connect via APM planner.2nd challenge is that I have connectivity via com15 through the mission planner but when I go to the setup page (in APM mission planner) for the 3dr radios, and click on download settings I get an error message that the com port is incorrect.Thanks for your help,Matthias

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  • Fred ,

    Thanks for your answer. I have the com port  set to 57600 8N1N (as well as the Ardu Planner ( which I believe may be irrelevant for a software upload)

    At this I am looking for some instructions on how to "manually" talk to the boot loader and get the new firmware uploaded.

    Or figure out why I have a communication mismatch...

    Can anybody help me please?

  • Update - no success :(
    FTDI cable from Sparkfun arrived yesterday.

    Double checked pins and connected to my laptop.

    The Modem fired up and the APM planned saw it as  a local radio wit the old 1.3 software.

    I pressed the upload firmware button. It connected erased the firmware and ended with

    "Update Failed SYNC LOST"  

    Fail: lost Synchronization with Boot loader.

    The red LED stays on indicating boot loader mode.

    I tried 9600 baud as well as the 57600 with the same results.

    Suggestion welcome


  • TTL cable was ordered yesterday from Sparkfun I assume once I have the radios on the same rev my issues will go away.

    Thanks you for everybody's help.

    I'll keep you posted!


  • +++ that will be helpful l!  Thanks! I'll try that when I get home ...

  • Trige,

    OK so I reread the documentation and some other posts. and I conclude that both radios need to be at the same rev level.

    I received an unmatched pair.of Radios :( and in order to fix that I need an "FTDI" cable.

    (Or I could make my own can make my own Serial Cable).

    Will This cable work:

    Or Can You recommend a  better cable?

    To Clarify assuming you have a matched pair, The upgrade option in the mission planner does not help until ONE HAS A FTDI CABLE that will allow the upgrade of the remote radio as well.?!?
    Or can you Upgrade over the air if the radios talk properly?

    2nd Challenge

    I can issue AT commands to the Radio all day long but I am not getting an answer. ( echo)

    Its' been quite a while that I messed with At commands but ATE1 I believe should turn on echo mode.

    I am getting absolutely nothing back from the radio.

    Thanks for you help...


  • My Terminal Output Looks like this ( see below)  the command do not appear to be accepted

    I am using Putty

    BTW the my win 7 ultimate did not recognize the modem/ radio So I installed the FT232R Drivers

    The mission Planner was receiving data after that but It behaves different from using a USB Cable.

    I do not seem to be able to send commands to the APM with the radios.

    Hmmmm ....If I go to the Setup screen for the 3DR radio and click on "Load Settings"  the local radio reports Rev 1.5 the Remote is at  1.3  Is that normal ?

       KUy*øÃU%z O'C F<(ÝU{>ÀƸR½®U|I(þèU}%ZÛ
                                             ¬U~#ê[ÛÛÛÛê&UO3X½Û-<ȯ!?(6»r£»½z;;ÂÎ;(<­<ÓÐ5:ºUËU»½tj;;Çë;(2Ê<àï;Qê\ÛÛÛÛ¡U Tc̽yÂ<Ç6«?;¾H¢ºv¦ºA¦-»UJ@ƸRÜeU
              "ú'`è(~UxU~U*³`U% YÈC F<k±U>ÀƸRÈI(ËU%ZÛÌþU#ê\ÛÛÚÛ(
                                                                 U YD½ÅÚ<È>Ò?"7»MU£»½P;;Ý,;(^Ù<Ò $;¹ôkÂýU7UïU
                             ",'`è)UxÄU*:]U% ^¸@C  F<ä/U >ÀÃ×
                                                             fU¡I(_EU¢%ZÛ\U£#ê\ÛÛÚÛáSU ¤^Ľì<ÉÈ»

  • Developer

    Hi Matthias,

    It shouldn't lose the link easily. What parameters do you have set?

    If you use a terminal, try AT&T=RSSI and look at what is happening with the signal and noise levels. You could also do AT&T=TDM if you want to see low level debug information on the TDM synchronisation.

    Cheers, Tridge

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Aug 31
nick rymer left a comment on ArduCopter User Group
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Aug 20