New FrSkyX protocol

Detailed information about the FrskyX packet sequence number algorithm was posted here a few days ago. Thanks to Mike Blanford. I've implemented it in deviation. Tested on both FCC and EU; pull request submitted. Test builds are here . With this change missed packets are recovered without resetting the telemetry link so overall telemetry throughput is increased.

There is something going on with the LBT firmware and telemetry at close range. Testing with a Devo 10 with 4n1 module and XSR receiver, telemetry starts being interrupted when distance between tx and rx falls below about 4 meters, which is about -40db LRSSI. With FCC firmware telemetry reception is fine up to about 10cm and -10 LRSSI. Generally the error is the telemetry packet is not received at all, like the Devo is being swamped. Beyond 4 meters the LBT telemetry is solid.

Hello,

I have a Devo10 with 4in1 module, already tested it with some little quads in FrSKy standard protocol, in SBUS mode.
Today I've received a new Eachine Racer 250 Pro, I've connected a FrSKy XSR in SBUS to the UART3
I've managed to do the bind process between my Devo10 in FrSkyX Protocol (constant green led and no more red blinking led after switch on).
However, even if in Betaflight the FC has UART3 activated and Serial Based Protocol / SBUS, I'm unable to see any impact of my transmitter on the channel values

I have no doubt about the 2 ground and 5V wires since the XSR module is powered on with green led after binding so the power supply from UART3 pin ground and +5V to XSR module seems validated.
I have no doubt about the binding since the led behaviour is correct.
I've tested the 3rd wire for SBUS connection which is well connected from the XSR module to the RX pin of the UART3 on the FC (at least there is a continuity checked with ohmeter from last pin of XSR module which should be SBUS pin to the RX pin of UART3).
Maybe I'm wrong and SBUS pin of XSR is not the opposite one from ? But it's written everywhere :http://blog.dronetrest.com/content/images/2016/04/XSR-pinout.png
I'm quite sure of the Betaflight configuration : I've got the same configuration on another quad (except it's on a miniquad with receiver included on the FC, with the standard FrSky protocol

=> so I think about the devo file configuration ? the number of channels ? (configured to 8, I've also tried 12 but no more success)

Would you have an idea ?

By the way, I've also used another XSR module that I've received, and even if binding was a success, no more impact on the channel values

I cry a lot ...


Other elements that could help thinking about a solution :
* I've got a recent firmware for the Devo (from August 2017)
* The transmitter channel visualisation on the devo show that the channel values move (on the transmitter ...)

The SBus signal is inverted, so most of the F4 boards do have a dedicated Rx Uart Sbus input with an invertor.
For the F3 boards the uarts Rx signals can be inverted.

If no luck at all it is possible modify the Frsky RX, as XSR and X4R to solder a wire to the board and get the uninverted Sbus. Use Google.

oscarliang.com/uninverted-sbus-smart-port-frsky-receivers/

Thank you very much for your answer.
As I know that the FC is a F3, I understood that it shouldn't be the problem.
So I decided to investigate more on my soldering (which I'm not very good for ...), and after desoldering and resoldering the third wire (the one for SBUS signal), everything has worked... Even the RSSI signal level in dB seems to be present in the Devo10 telemetry menu (value lowers as the distance between quad and devo increases, so it seems to be working).
Thank you for your support !

Does anyone know why my Frsky S6R Receiver doesnt bind with deviation (latest nightly)
tested both FCC and LBT.
Put S6R Receiver in bind mode,hit bind on TX as usual, RX goes blinking as usual...but after repowering RX, red led is blinking....
Tuning Fine variable doesnt help

Taranis with multimodule doesn`t bind, too.

EDIT: Tried another Fixed ID and now it works

Taranis with internal XJT works as expected

Hi all! I'm stumped - I have two XM+ receivers that bind perfectly to my new T8SG Jumper dedicated Devo receiver using the FrSkyX protocol and a FreQFine of -40. The RSSI is set to LASTCHAN, but no RSSI appears on any channel on the receiver page of Betaflight 3.2.1. The T8SG only has 12 channels, and the RSSI output from the XM+ is supposedly on Channel 16 - so, how does that work? It is possible that both XM+ receivers lack the firmware to put RSSI on channel 16, but, assuming the signal is present, what am I missing? I've tried everything I know how to do, and have been using Deviation for years - but it seems logical that the receiver has to be able to access 16 channels to pick-up the RSSI feed on Channel 16. Any help is appreciated!

gvhlaw wrote: Hi all! I'm stumped - I have two XM+ receivers that bind perfectly to my new T8SG Jumper dedicated Devo receiver using the FrSkyX protocol and a FreQFine of -40. The RSSI is set to LASTCHAN, but no RSSI appears on any channel on the receiver page of Betaflight 3.2.1. The T8SG only has 12 channels, and the RSSI output from the XM+ is supposedly on Channel 16 - so, how does that work? It is possible that both XM+ receivers lack the firmware to put RSSI on channel 16, but, assuming the signal is present, what am I missing? I've tried everything I know how to do, and have been using Deviation for years - but it seems logical that the receiver has to be able to access 16 channels to pick-up the RSSI feed on Channel 16. Any help is appreciated!

I don't use betaflight but I use XM+. The RSSI signal is generated solely by XM+ and has nothing to do with the number of channels on the Tx. If I recall correctly stock XM+ comes with no PWM RSSI but you need to flash a different FW (downloaded from Frsky wesbite) to enable PWM RSSI output on either ch8 or ch16. I suppose the PWM RSSI is then decoded by the flight controller and displayed on the PC.

to what ajtank was saying about the XM+ not coming with RSSI enabled. I have a number of XM+'s and it a total roll of the dice which firmware is installed on the RX. You MAY have to install the correct firmware which is a bit of a pain without a taranis (there's a way with a frsky thinger "FUC-3" or something and also with an FTDI).

but also...

can you see 16 channels in BF?
if not... this should help (i don't know LASTCHAN - but that's not a command i've used... i just use the gui to select channel 16 on the receiver tab.)

Thanks to AJTank and CesiumSalami (boy is that a cool name!) I think you are right about the firmware - and even though these are recent make XM+ receivers, they probably need the updated firmware. I don't and won't have a Taranis TX, so I guess Ihave to borrow one or learn the mysteries of a FUC-3 or an FTDI.

vlad_vy wrote: LASTCHAN = model number of channels. If you use 12 channels LASTCHAN = 12, Betaflight "Receiver" -> "RSSI channel" = AUX8.

Thanks Vlad - I think the CLI command for RSSI channel may help - but I tried using AUX 8 on the Receiver page for BF 3.2.1 and nothing changed (no joy).

@hexfet
Mike had a look at the telemetry problems in EU LBT mode, and got it solved changing the timing.
www.rcgroups.com/forums/showpost.php?p=38484818&postcount=10107

Can someone post a picture of his frsky smartport X, series receiver connected to betaflight telemetry output?
What do kind of data you see in your devo screen? Voltage amps Mah etc? does it work fine?

Wene001 wrote: @hexfet
Mike had a look at the telemetry problems in EU LBT mode, and got it solved changing the timing.
www.rcgroups.com/forums/showpost.php?p=38484818&postcount=10107

Thanks, I did see this but haven't had a chance to test it in deviation yet. Will check soon.

The deviation timing is already different than multi-module was previously, and the difference is in the same direction as the change Mike made. Didn't you report that EU telemetry behavior on deviation was somewhat better than multimodule? This difference could explain why.

With Mikes changes my FrskyX telemetry is working reliable in International and LBT Mode.
Hope this works in Deviation, too...

Hi,
What can i do to get RSSI on my OSD with a XSR receiver?
Telemetry works for me, I can see VBat,mAh, LRSSI,LQI,CRNT..... but there is no way to Send that LRSSI value back to my Flight controller
With a X9D you can put that Telemetry value back to a Channel you want, but is there any way to do that in Deviation?

I don´t want to use the Rssi pad on the RX/FC, it would be cleaner if there is another option

If I recall correctly, FrSkyX protocol has a protocol option (press ENT on the protocol in model setup and scroll down) to send LRSSI back on the last channel.

Do i need the latest nightly for that?

With vlad´s Build from i think 08/17, it looks like this:



There are only 4 Options!

The feature was added in March 2017, but vlad missed including it in his build until October 27th. Remember you will have to scroll down, as there only four protocol options displayed at one time.