Smart Port Telemetry on Naze 32



Using FrSky smart port telemetry on Naze 32 flight controllers is a little tricky to get working due to the limited number of UART ports available on the naze 32 flight controller with F1 processors. Using other naze 32 compatible flight controllers with F3 processors such as DoDo F3 make things abit easier.

However if you do have a naze32 and want to use your X-series receiver (such as X4R) with telemetry here is what you need to do. There are two options, the first one which is better is to setup your receiver to run in CPPM mode and not SBUS. However each option has some limitations due to the limited UART ports.

You cannot simply use the X-series telemetry connectors on the Naze32 since the newer X-series receivers work differently, but if you are using a Frsky receiver such as the D4R-ii then connecting telemetry is very easy.

Option 1 - Use CPPM and UART 2 for telemetry

This is the preferred method where you bind your X4R receiver to output CPPM, and connect that to RC pin 1. You can still bind your X4R-SBUS receiver to CPPM mode.

You then need to short out the UART2 RX and TX pins. The reason why you need to do this is because the smart port works on half duplex, which means that it uses the same wire for both TX half the time, and RX for the other half. By connecting both the TX and RX pins together we can emulate this. The best way to do this is not to solder anything, but rather create a cable that shorts the two together.

To enable telemetry you need to enable the Smart Telemetry on the UART2 port in the configuration of cleanflight. You must also remember to use the CLI to invert the telemetry, To do this you set the select_telemetr_inversion = ON

Option 2 - Use SBUS and Soft Serial for telemetry

Although the Revision 6 of the Naze 32 has direcet support for SBUS, this uses the UART2 port on the flight controller. This means that you will then need to enable softserial to emulate another two UART ports so you can use one of them for telemetry. However the problem by doing this is that you cannot then use an RGB LED with your quadcopter since softserial uses the LED pin for this.

Just as before you will need to short the TX and RX pins (RC pins 5 and 6) to emulate half-duplex mode for telemetry.

Now you just need to set the softserial port to be smart port telemetry and again you must also remember to use the CLI to invert the telemetry, To do this you set the select_telemetr_inversion = ON

Hope that helps and if you have any other questions please let me know below.

Naze 32 Revision 6 Flight Controller Guide
Naze 32 Revision 6 Flight Controller Guide

I am so close to having this thing up and flying! This is my current set up, not to clear so I will try to explain ! SBUS to CPPM converter to use sbus port on X8R but CPPM on naze32 to have gps running on UART2. I have VBAT enabled and want the telemetry (Using the smart port maybe?) on my taranis transmitter. Any Ideas Alex? Thanks for your help !


Are you using softserial and are you sure it is connected to the correct port RC5?
Also what are your port settings like on cleanflight as you need to select smart port as the telemetry and not FRsky in your cleanflight port settings. I have explained this abit in our SPracing F3 flight controller guide


I had my port settings in Frisky not Smartport, Still having trouble with the connections. I have set telemetry inversion to on but still no new sensors discovered on my taranis. Tried a combination of set ups. What plug to i need to connect to what? i tries port 5 to the S plug straight to my receiver with no luck. Thank you so much !


Also I forgot to say that when your FC is disarmed it will not output any telemetry since you are using softserial, so you will first need to arm your board before discovering sensors. Hope that will work


IT WORKED !! Thanks so much Alex, I had to connect port 5&6 with the singular S port receiver. I seem to not be able to get individual cell voltages or the correct altitude. (showing 3300 meters :joy:) Any ideas on what i could be doing wrong ? thanks !!! just had to arm the board ! you were right :slight_smile:


You can’t get cell voltage as naze only measures the total voltage. But you can setup your taranis to display cell voltage by dividing the total voltage by cell number


Can you show me how to do this ?? thank you so much ~~~~


Do you need to know how to setup the battery voltage monitor?


Yes, now I can get VFAS but don’t knwo how to " display cell voltage by dividing the total voltage by cell number "

Frsky xsr reveiver 、SP Racing F3 controller


Alright so it’s just how to setup your taranis radio to show the voltages? If so here is a video to help you setup the voltage to be read out from your taranis as you fly.


My point is how to " setup taranis to display cell voltage by dividing the total voltage by cell number "

I know how to setup VFAS in the telemetry page , but how to setup 「single cell voltage」????


You can’t :frowning: as the naze only measures total battery voltage



Yes, but its not the true cell voltage, its simply just the number divided by 3.


Yes, I know. The question is how ?


Instead of displaying cells, simply select cell within the telemetry configuration screen. The video playlist that I linked has full details on setting this all up -


Just a quick clarification, when you say set your serial port to be smart port I am assuming you mean that uart 2 can be or will be both a serial and a smart port?


When I say serial I mean UART. Smartport is just a serial protocol that frsky developed for their modules to send/receive telemetry info and our flight controllers just tap into that as an extra sensor :slight_smile: