Hi. what is the use of Fathom X interface board

I couldn’t find any info on the function of interface board in ROV. I tried connecting my raspberry pi to Qground control and the raspberry has pixhawk connected to it with firmware updated…but Qground control is not detecting the pixhawk… is there is any work of interface board in this part… please help me just understand what is teh use of interface board.

Hi @auvproject, welcome to the forum :slight_smile:

A tether interface is translation/conversion hardware that allows using tethers that are not ethernet cables. A Fathom-X pair allows sending an ethernet signal over a single pair of wires, and over long distances.

Instead of
Onboard Computer (Raspberry Pi) ← ethernet → Control Station Computer (topside)
you can do
Onboard Computer ← ethernetFathom-X ← wire pair → Fathom-Xethernet → Control Station Computer

Other interface boards can be used for fiber optic communication, in which case you would replace the “Fathom-X ← wire pair → Fathom-X” part with “Board ← fiber → Board”.

No, the interface boards are not directly related to whether the Pixhawk is detected, although if the interface boards or tether are not working then no communication will be possible.

Have you gone through our software setup instructions? Assuming you’re running BlueOS (or our old companion software) on your onboard computer, are you able to access the web interface (try

hi eliot…I’m able to access BlueOS interface, but no through but through a different IP address which I used to SSH the raspberry to my computer using Putty. I got this IP address from the command line “ifconfig”. I used this because the one u mentioned is not working. using the blue OS web interface I’m able to turn off and on the pixhawk but I couldn’t install any firmware in pixhawk.

Blue OS interface- is working when raspberry is connected through ethernet cable and following the software instructions. but when connected through putty via wifi, BlueOS web interface opens when used the other ip address.
but in both the cases, I couldn’t update pixhawk flight controller.

If you have connection to the BlueOS web interface then changing how you’re connecting to it will not influence whether it can update the Pixhawk firmware. Updating the Pixhawk board firmware requires

  1. A (working) direct USB connection between the updater computer and the Pixhawk
    • the updater computer can be a Raspberry Pi running BlueOS, or a normal computer running QGroundControl
  2. A firmware file (or internet connection to download one through)

What was not working?

  1. Was it unable to detect the Pixhawk?
  2. Was it able to detect, but the update did not succeed?
    • Try updating to a beta version of BlueOS, as above
  3. Something else?
    • Please provide some further information