Gents I need your help.

I recently upgraded one of my 2.6APM powered quads to a Pixhawk.  One of the reasons I went ahead and did this is because the Pixhawk is supposed to take PWM RSSI signals directly (into the Sbus port aka Pin 103) and I could ditch my PWM to analog conversion circuit is used in my APM.

I have verified that my EZUHF receiver is outputting RSSI in PWM form on one of the channels. (it will move a servo appropriately when the RF gets weak or disappears... and it worked fine for the APM as an RSSI input via a PWM to analog conversion circuit)

And, I have hooked up the PWM RSSI output to the Sbus port (pin 103).... it does nothing.  Shows zero RSSI on the OSD no matter what.

I can't find any useful description of how to configure this in the wiki, mission planner or this site.

How do you make a Pixhawk show RSSI from a PWM input on pin 103 as its advertised?

Thanks for your help.


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Steve!!! Thanks a lot Man!!

So, I was able to bind, but I did had to update firmware on my TX up to 1.50...

I just run a small test and pixhawk its reading ezuhf now :)

I didn't wanted to get back to u unless I had tried it... I really appreciate your help!




Got the EZUHF RSSI/Link to work with my Skywalker APM 2.6 plane.

The RSSI has inverted values and extra percent sign problem but it works!

What I used:

EZUHF TX/RX firmware v1.50

ImmersionRC Config Tool v1.40

MinimOSD firmware Extra Plane v2.4 Pre-Release r719

Config Tool for MinimOSD v2.4 Pre-Release r727

No settings needed to be changed in the APM Mission Planner

RSSI MIN/MAX 993/1650

Link Quality MIN/MAX 1074/1794


Here is a tutorial video I made for the EZUHF RSSI / Link Quality with APM 2.6 or Pixhawk 

Dear David, I follow up every step on your video, I have the same or even newer firmware in the Minimosd, but the RSSI appear lower when the transmiter is on, and higher when the transmiter is off, so the Link strengh is near 0% when is full strengh and near 100% when the transmiter is off, what I did wrong?, thank you for your very valuable assistance.
Rob: did you solve the problem of inverted values?, in my case, RSSI and Link Qty gave me the same inverted numbers, big number for transmiter off, and small one for full signal, your experience with this matter would be frankly appreciated.

You have done nothing wrong.

Unfortunately the RSSI is inverted with the EZUHF. 

In the movie you will see that I chose to use Link Quality which is non-inverted and responds to degradation from interfering signals. In my opinion Link Quality is the better choice anyway.

I am not sure, but eventually I chose the link quality on chanel 8, so I cannot understand why it shows reversed on the Minim osd, but I will repeat the procedure to be sure before complaint.


trying to set this up and I find when I assign EZUHF LQ to channel 8 I lose my flight mode selection

Using the latest APM plane on an APM 2.6

Any clues Gents, this is driving me spare!


I moved my flight modes to a different channel.

Look a about time code 2:17 in this video for the schematic and explanation:

Thanks David

I have watched your Video a couple of times, very well presented

I am using CPPM and want to keep it that way

My problem is I cannot figure how to switch my Flight mode select channel to anything other than Channel 8 (I'm using Arduplane 3.2)

I note in your schematic you use channel 6, how did you change that from what appears to be the default of channel 8

To confuse the issue more the current setup wiki says to use channel 5 which doesn't work for me

I changed the flight mode channel input from the default 8 to 6 in the mission planner and then wrote the settings to the APM. 

Got That

Please forgive my stupidity but I am asking how to do that

What parameter are you changing and where do I find it?

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