External USB port for Pixhawk Cube

For our closed housing copter with pixhawk cube I would like to add an external USB port for easier downloading of the log files. It will look like this:

Do I risk any kind of vibration when connecting to the cube mini c port, that is on the vibration dampened platine ?

Is it a better solution to customise a cable and connect it to the USB ?

Much better to use the JST connector

Both solutions will work; I have tried both.

Just using the USB port on the cube is fine, although I suppose whether it might introduce vibrations depends on how you mount it and how stiff the cable is. I had no problems with vibrations, although if you do this, I recommend adding some hot glue, putty, or Sugru around the connector on the cube to make sure any cable strain doesn’t damage the connector.

The second option with the connector on the carrier board is probably the “correct” way, unfortunately there are no off-the-shelf solutions for external USB for the Pixhawk 2, so you’ll have to hack something together. The old mRo external USB and CRIUS USB/LED modules for the Pixhawk 1 do work, but you’ll need to customize the cable, so it’s just as easy to hack up a regular panel mount USB cable like the one you showed. My advice here is to double-triple check the order of the USB pins on the Pixhawk 2; I recall the documentation being wrong or upside-down and getting it wrong the first time. Or maybe it was me that was upside down.

Thanks for the fast answers!
So I did cut off the USB port cable and one of the original Pixhawk2 power cables…

This are the wires of the Standard USB

This is, what the USB Buzzer port Looks like:

White “Data -” from USB to “D_MINUS” to pixhawk, or does it have to be crosswise with + to - ?
Sorry for the stupid question, but I am not familiar with this electronic stuff…

Minus to minus.

If the data cables end up being swapped, nothing bad will happen. The USB connection won’t work, but there will be no damage so you can just swap them.

Thanks Rick!

This is the result now:

When I connect Laptop and copter, the pixhawk gets power and is blinking, but there is no com port shown and the mission planner does not get a connection.

No idea, what is the problem… I will check the soldering again…

edit: HMMM…soldering is checked and is fine…changed Data + and - with the same result…Pixhawk is powered, but no com port shown.

Thats the end of my limited knowledge now :wink: …any help welcome!

Does the shielding has to be connected also??

Or does the USB Port Need any Settings via Mission Manager for USB function?

I remember having trouble with this cable in the past but couldn’t remember why, so I made a new one to refresh my memory:

The diagram you posted is correct; connect signal - to - and + to +. A strange thing, though, is my cable did not work the first time I tried it, so I swapped the signal wires by moving the connector pins and it still didn’t work. Thinking maybe it was a power issue, I tried powering the Pixhawk separately with a power module and connecting the USB afterwards. This didn’t work, so I swapped the signal lines back to match the diagram and tried powering it separately again, and it worked. The odd part is that now it works when being powered through USB alone, in the same configuration as my first attempt that didn’t work.

Unfortunately I can’t reproduce the issue I had with my first attempt, so I’m not sure what to say in case you’re having the same problem. I can only guess that one of the pins in the connector was loose, and by swapping them back and forth I secured the loose one. Maybe try powering the Pixhawk separately like I did.

Oh, and to answer your question: the shield drain wire shouldn’t need to be connected. However I recommend twisting or otherwise bundling the cable, because USB uses a differential signal and can sometimes be unstable if the signal lines are physically separated.

Thanks for your time Rick! I appreciate it!
I also powered the machine with the power module and its batteries, but it makes no difference.
The USB Connector is not seen by the Computer.
I also twisted the cables now, although I do have a short cable, also this makes no difference.
Kind of strange…perhaps thats the reason why nobody offers ready to use cables;-)
I think I tried now every aspect, but with no success, so I dont see any other solution than using the “real” USB Port in the cube and position the cable that it will not cause vibration .
Thanks for your help! If any other ideas are coming up, I will have a look at this thread!

Believe it or not…I made my thoughts and came to the conclusion that it can just be something with the USB cable…Diameter…resistance…whatever…
I did cut another USB cable and simply did use a green 6 pin multiplex connector…works!!!

To get things done properly I just ordered a USB 3.0 Type B, which is a solide and robuste type …lets see, if this is working also!

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