FrSky Telemetry on DeviationTX

Hey folks, trying to figure something out. I have an Eachine Tiny F3 brushless FC connected to a FuriousFPV FrSky Micro RX and trying to get Telemetry working on my Devo transmitter. I have a nightly that supports the D8 protocol and am able to bind with the receiver and fly the quad. I have TX3 on the FC connected to the Telem port on the RX and have telemetry enabled on both the Config tab as well as the Ports tab of Betaflight (UART3). On the transmitter, the voltage box is white on the Telemetry Explorer screen, but it sits static at 12.3 volts which is way off for a 1s battery. Punching the throttle and such does not change this value, it appears to just sit there.

Any thoughts on the best way to start validating this chain of communication?

Install the latest nightly build. It has an important fix for Frsky hub telemetry.

Which "voltage box" are you talking about? In section 10.15 of the user manual here appropriate for your transmitter, what value are you referring to?

The RSSI, Volt1, and Volt2 values are in the "receiver" telemetry - they don't depend on the connection to the FC. If those are the only values that are white then you're not getting telemetry from the FC. The Volt1 value is RX voltage which should be around 5V, and Volt2 reflects the receiver's analog input (if connected).

Sorry about that, Wasn't thinking when I typed that apparently. I'm talking about the Volt1 and Volt2 boxes on the Telemetry screen.

When I open both the html as well as the pdf versions of the manual, there is no section 10.15. What I'm referring to are the screens in 7.5 of the Devo 8 manual. Mine looks like the top screen, but everything is red besides the Volt1 and Volt2 fields.

I'll do the nightly build update in the next couple of days and post back.

iirc that rx requires

for telemetry to work, have you set that on cf's cli?

The link above is to test builds of the manual that include recent Frsky telemetry updates. It's section 10.15 in the 10 manual, and 9.15 in the 8 manual.

Couldn't find any documentation for that receiver on the manufacturer's website. Did it come with a manual? The web page talks about hub telemetry, but RSSI, Volt1, and Volt2 don't come from hub telemetry. In a rx from Frsky Volt1 is the receiver voltage, and Volt2 comes from an analog input that doesn't seem to exist on the Furious rx. Since you're getting Volt1 and Volt2 but not RSSI maybe Furious puts some other values in those bytes in the telemetry packets? Anyone reported successful telemetry from those receivers to a Taranis?

HappyHarry wrote: iirc that rx requires

set telemetry_inversion = OFF

for telemetry to work, have you set that on cf's cli?

Yes, I disabled both Telemetry and SBUS inversion as FuriousFPV's instructions specify.

I also did an update to the latest nightly as of about 12/9. The situation hasn't really improved. The telemetry screen looks pretty much the same with some values going white. I seem to have lost the ability to display RSSI which I had before.

Hexfet, the instructions for the RX are here . I'm new enough to FrSky and Telemetry that I don't understand the difference between Hub Telemetry and other variants. I'm not actually getting Volt1 and Volt2, they're turning white on the TX in the Telemetry screen but the outputs are not correct.

To add, this is my first every telemetry setup on my Devo8s. I have two other D4r-ii builds, maybe I'll get those going first then come back to this one.

HappyHarry wrote: iirc that rx requires

set telemetry_inversion = OFF

for telemetry to work, have you set that on cf's cli?

Yes, I disabled both Telemetry and SBUS inversion as FuriousFPV's instructions specify.

I also did an update to the latest nightly as of about 12/9. The situation hasn't really improved. The telemetry screen looks pretty much the same with some values going white. I seem to have lost the ability to display RSSI which I had before.

Hexfet, the instructions for the RX are here . I'm new enough to FrSky and Telemetry that I don't understand the difference between Hub Telemetry and other variants. I'm not actually getting Volt1 and Volt2, they're turning white on the TX in the Telemetry screen but the outputs are not correct.

To add, this is my first every telemetry setup on my Devo8s. I have two other D4r-ii builds, maybe I'll get those going first then come back to this one.

Probably a good idea to try with a known receiver. D4Rii is what I've been testing with.

The Frsky D and X receivers always send telemetry packets containing RSSI, Volt1, and Volt2 (which I called "rx" telemetry). When bound these should always be active (white background) on the display. With a recent nightly the LQI and LRSSI values will also be active. These come from the local radio device.

The D series receivers also accept "hub" telemetry on a serial data input pin. This is what's sent by an FC or other sensors. In Frsky D equipment the sensors plug into a hub device hence the name.

The X series receivers also always send the rx telemetry values. Additional telemetry data can be added on the S.Port connection (serial data bidirectional pin).

Thanks Hexfet. It's intresting that my Volt1 and Volt2 don't seem to correspond to my quad. With it being a 1s micro, the top voltage on the system is the 5v connection between the FC and the RX. That voltage is stepped up from the ~3.7v from the battery. After updating to a more recent nightly, Volt2 is showing in the area of 11.8v and updating frequently while Volt1 shows a static figure in the neighborhood of 12.3v. For now I think I'll just solder a buzzer onto the FC to let me know about low battery voltage and come back to this later.

The receiver voltage is set fixed, it is just the voltage at the rx.
The ad1 analog monitoring pin voltage at the Rx manoitor a voltage 0 to max 3v3. You can use a resistor devider to scale down the voltage like I use 22k - 4k7.
In the Frsky protocol option, you can then have to tune the scalefactor (trial and error) to get the excact pack voltage displayed.

Google.......search.
"FrSky sensor ratio.xls"

Thanks aMax. How do you go about calculating the two figures on the bottom and where do you input those to adjust the voltage readout?

This spread sheet is only for calculating the values on voltage warnings /Frsky.....
but useful to play with the divider combinations.
Since the rx only sees the stepup voltage, which is constant, you must build a divider
for A2, ...if you have this input.
Edit: If you had one of these,no problem.
www.banggood.com/Tiny-Frsky-8CH-Receiver...63.html?rmmds=search

Sometimes I fly my drone on 3s and on 4s packs. The low battery alert then needs to changed, which is annoying.

Ideal situation still for monitoring pack voltage, would be to check the lowest lipo cell volt, this should also always work.
Anybody tested this is it possible to connect Frsky lipo sensor to the balance lead and make alert for lowest cell, 3.5V etc?

Which Frsky protocol are you using, plain, V8 or X?

If you don't mind my asking, did you use the very bottom pad for GND, or the one above it? There are 4 labels for 5 pads, and Furious seems to have pulled this from the market entirely, so there's no documentation or anything left.

You can still find it here: www.readymaderc.com/store/index.php?main...nfo&products_id=6402

I connected my wires using the bottom as GND and going up from there, leaving the very top pad unused. I'm using the V8 protocol.

Thanks, that was helpful. I also discovered that, unlike the other FCs I've used, this one won't power the receiver via USB, it has to be on filtered battery power.

So now I can get it to flash green, but it won't bind to my Devo 7E. To doublecheck that my Frsky module was working I just bound with my QAV210 just fine, which uses Frsky-X.

Always a struggle, right? :]

I'm on:

Tx power: 100Mw
PPM In: None
Frsky-V8 (I tried all 3)
Fixed ID 123456
# Channels: 8

I'm using mine off of a micro brushed FC from Eachine and it's powering up just fine on the 5v rail coming from that. I like that plugging the USB in for the FC powers up the RX as well.

Have you messed with the Freq-fine setting at all? This adjusts the frequency for variances in CC-2500 chips. I recall a process that someone posted instructions for on how to find the sweet-spot for adjusting it but I can't find that now...

My current issue is that the only telemetry that shows up is the +5v rail, despite having the telemetry hub. My friend's Taranis can ready the telemetry perfectly fine but it doesn't appear to work correctly on my Devo for some reason.

The V8 protocol does not support telemetry - the telemetry screens say not available. According to the information at that link the Furious board is D8, which is plain "Frsky" in deviation.

The 7E doesn't have enough memory to support extended telemetry even if that receiver sends it. You should get RSSI, receiver voltage, and the analog input voltage if the receiver is sending them.

Adjust the fine frequency setting up and down until bind is lost, then set it at a value halfway between.

There doesn't appear to be a fine frequency setting for Frsky-V8. I have it for both Frsky and FrskyX (which I use at -45 for my QAV210), but V8 doesn't seem to have any such options.