UART 2 for Telemetry on APM 2.5

Hello! I need to use UART 2 for telemetry on APM 2.5 so that I can use both USB(multiplexed with UART0) and Xbee telemetry(hopefully on UART 2). I have followed the directions given on the google code page, and this is what I have done.

-Cut the two upper bridges on the AUTOMUX UART0 pads provided underneath the APM.

-Soldered the two corresponding lower bridges. Verified using short test through Multimeter.

-Downloaded the Arduplanev2.68, edited config.h to

// use this to enable telemetry on UART2. This is used
// when you have setup the solder bridge on an APM2 to enable UART2

and then successfully compiled and uploaded the firmware on the board using arduino 1.0.3 (also downloaded from APM google code page).

Now, I tried use the UART 0/2 port (default telemetry port on APM2.5) but i get no data there. 

Then I tried using UART 2 provided on the side (soldered pins there) and used TX2 and RX2, all I got was heartbeat at 1 hz, and no other data.

What am I doing wrong here ?

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  • I have this working on ArduPLane, but what about ArduCopter? I cannot get it to work???

  • Hi Bharat!

    I am currently trying to connect my RCtimer telemetry module to my APM 2.5 though the UART0 port (not the regular UART0/2 telemetry port) since there is only RX, TX, 5v and Gnd coming out of my telemetry module. The thing is that i did not quite understand the solder jumpers thing... I am not planning to add OSD at the moment, but if you have any idea how to get this thing to work, i would really appreciate it!

    Here is a picture of my APM, without solder jumpers, if i am right...

    EDIT: actually, it seems that there if  tiny bridges between the first two rows... do i need to break those bridges, and solder in the same way the two bottom rows?


  • did you ever get it to work?

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