Can't connect to UART telemetry , receiving garbage on putty

Hello, n00b here!

I am trying to connect my windows 10 laptop to my drone via 3dr telemetry modules. I successfully connected Mission Planner but I also want to have connection to the RPi terminal via Putty. I set putty to serial and 57600 baud rate as MP has it, but I am receiving garbage. Can anyone help me please?

Hi Jon,

if you have one serial link and ardupilot uses it for telemetry, you can not use this link for anything else. What you see in putty as garbage is the mavlink telemetry.
A serial link is not like a network connection, where multiple applications can share the connection by using different ports.

Thank you for your response Sebastian.

Do you see a way to connect another telemetry to the navio2 so I can communicate with the RPi separately from MP? My goal is to code dronekit scripts for semi-automated missions that will utilize computer vision via the attached Pi Camera but also allowing for user input to change the mission on the fly.


You can stream video and access the command line of Navio2 using a Wi-Fi connection. However, it will require a good Internet connection. I’d suggest taking a look at Karl’s comment in this thread regarding live camera usage and object detection.


actually, you don’t need an internet connection at all. Just a WiFi router to link your drone to your GCS.
Now I know lots of people out there can’t fly near their home for various reasons. Needles to say away at an open field there wouldn’t be a WiFi connection available, but here are three options regardless:

  • -If you really want to use WiFi you can use a spare Router and as most have a plug-pack attached to it simply replace it with a 12V cigarette lighter socket cable for your car. ( But you need to check first if your router is actually running on 12V - check label at rear & or label on plug-pack)
  • -You could use a 3G or 4G USB wireless broadband modem. In that way you can make use of the mobile phone network (cell-network) instead of WiFi - (providing there is a signal where drone is flown)
  • -Finally, you can install a virtual router software on your computer / tablet or whatever else you are using for your GCS. This will simulate a router and allows direct connection to your drone without any additional hardware. - However, some devices out there have a rather poor WiFi module installed and hence have a shorter range compared to a good WiFi router.

Hope this is of some help.

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Thank you for your responses guys, but actually, I will transfer the video from the RPi’s comppsite video out and relay it to GCS via a video transmitter on the drone. I think 4G modem will work well to access the command line but I would also like to know if I can use a separate radio to do this?

The reason for the composite video thru VTX is that I require minimal latency and I am willing to compromise on video quality.

The 4G connection allows for both, telemetry and video with low latency - providing you got a reasonable fast connection.
(Some mobile internet providers will limit data speed on pre-paid and low cost services)

Whist you certainly can use a different transmitter I would not recommend it for following reasons:

  • More transmitters = more possible interference with other close signals like telemetry.
  • More transmitters = higher likely-hood of problems with interference affecting FC
  • Limited Range - from my own experience I know such transmitters usually only work well within 50m or so. But 4G could work even at the other end of the world providing you’ve got signal reception.
  • Legal Problems - Many countries have legal restrictions in regards to transmitter power. Whilst there are stronger transmitter out you could get yourself into trouble if you get caught using such a device - Check with your local authorities.

Hope this is of some help.

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