I will soon be beginning a UAV project (as soon as my board arrives) and I am considering my options for telemetry. I know that, at least to begin, I would like to use xbee radios as I am familiar with this hardware.
When it comes to connecting them to the board, is there any advantage to using the UART port over a USB port? Does one provide a faster or more reliable connection to the Navio+ or is it really just a matter of preference?
There’s not much of a difference. UART is simpler so may be considered a little bit more reliable, but USB radio should do good as well.
Okay, that is good to know. The reason I ask is that I would like to use both a telemetry radio and an osd, such as the minimosd from 3dr. Would it be possible to connect an osd to the USB with an FTDI adapter? Alternately (and this is mainly a question of curiosity), could you connect both devices to the UART using a cable splitter? I know this is frowned upon in video systems as it degraded the signal. Just curious if the same applies here.
Yes, you can use virtually unlimited number of UART devices using USB-to-UART adapters such as FTDI.
Usually single UART cannot be used for connecting multiple devices as there’s no collision handling, but I remember that some OSDs only listen on the line so it may be possible depending on the model.
Okay, that is very helpful. I will try both and see what works best with my components.