Problems with UART1 on Naze32

Hello together, I have some strange behavior to report.

I tried to switch serial communication (between FC and Companion Computer) from USB to UART1 as it is recommended in the docs (because vibration could losen the connection).

With Flip32 everything is working as expected, but when switching to a Naze32 (due to angled connectors) it is working only … ehm partly. When checking the logs, the firmware-version print is missing and it doesn’t stop to complain about missing parameters. When arming the FC with the RC, it suddenly finds all parameters. But _get or _set of parameters is not working so this is not really useful.

As I found in the Naze docs, UART1 and USB are sharing the same serial port, so in my tests I didn’t connect both at the same time as recommended. USB is working as expected but UART1 is not. At the moment I am using USB-connection, but I would like to change to UART1 if possible in the future.

Is there any explanation for this behavior?

Regards Rafael

I don’t currently have a Naze32 available, but I have a Flip32 v2.5 with me. I am connecting to the UART using an FTDI adapter, connecting GND, TX, and RX but not VCC. When I power the board through either the RC or PWM rail, everything works fine for me. However, when I power the board with the USB connector (USB plugged into a power socket but not the computer), I get behavior similar to what you’re describing. It seems like transmission from the flight controller to the computer works fine, but the other direction does not work (this explains why the version number and parameters are not received, since those are only sent when the flight controller receives a request from rosflight).

How are you powering the board? If you’ve been powering it with the USB port, does powering it over the RC or PWM rail instead fix your issues?