Adding a second telemetry connection

I am planning to make a VTOL with a Chumby on board to perform some environmental calculations that the APM cannot do at the moment. This will require the drone to hover for awhile while to do this. I do not know the locations that will require the VTOL to hover, this is what the Chumby will do on the fly.

I would like to connect the Chumby using the remaining serial connection (assuming I have an IMU, XBee telemetry, GPS). Is it possible to treat this remaining serial connection like a telemetry in order for the Chumby to issue commands to the APM? I plan to use another switch on the RC unit to toggle the ability of the APM taking commands from the Chumby, similar to Autopilot control switch. This is so that I can still send waypoints using a GCS and not combat the Chumby also sending commands.

I haven't bought my Chumby board (still trying to decide if I can use the gen 1 or if I need to go ahead and get the CHB) and I am also waiting for the newer APM to be released. I haven't done any work on either platforms, this is more of an inquiry of 'is this possible?'

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  • Oh, I didn't know that the ADC (analog to digital converter right?) used the fourth serial port.

    Do you have any recommendations on how to get the APM to communicate with a Chumby?

  • 3D Robotics
    I'm not sure what remaining serial port you're referring to. The fourth serial port is used by the ADC.
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