XK K110 (S-FHSS) build for Devo 7E and Devo 10

dc59 wrote:

Fernando wrote:

victzh wrote: I hope by the time you get your module it would be propagated to the main build.

Hi victzh!, the CC2500 module arrives before than expected from Banggood. I already got it and maybe today or tomorrow will make the mod to my transmitter Devo 8s. Is the protocol already included in the latest nightly on this wesite? Can you (or someone) provide me a Devo8S XK-K120 model?

Thank you

You can find my DEVO10 config file for K120 as below,it should be used on 8S.

www.deviationtx.com/forum/builds/5569-xk...vo-10?start=20#44758

It works! Thank you very much.

Today I have installed the CC-2500 module and everything went fine. I also have a NRF-24L01 to bind my v977 and Hisky HCP100s and sometime ago I managed to mount a vibrator motor as you can find it here .

After turn off and on several times testing my models suddenly the screen does not show anything when powered up the radio , the screen was just white, no info. To be sure there were no problems with the new installed module or the customization, I bind my K120 perfect so the radio was working but no information on the screen. After some tests I determined that when I activate the vibrator motor it happens like that, but If I deactivate it, my Devo8s powers up correctly and the screen show up all the info.
So I am not sure what is happening but It seems that the battery is not able to manage all electronics (boards, modules, screen, vibrator...) at the same time. Do the external modules (NRF, CC-2500) are powered up even if I am not going to use them with my chosen model?

Well, I was almost right. To feed the motor, I took the power from the VDD/GND pins that are on straight connector together with the signal pins TCK, etc. With just one module there were no problems but with two modules, the electronics and the motor, I thing the output voltage regulator is not able to power them all, so may be the voltage drops while booting up, affecting mainly the screen. I tried gettingt the power to the vibrator motor directly from the battery connector and it worked. Anyway, let a module powered up if I am not going to use it...is not a good idea. May be an external switch to choose which one you want to use at a time would be a good idea.

I never got white screen issue on my 8S,can't give you suggestions , but if you can post some pictures about your module wiring, I think you will get more help , there are many Master/Expert in here.

Thanks for your suggestion but I solved it feeding the motor directly from the batteries and not after the regulator. Consumption is quite high while booting up.

Edit: Added my re-configured model, just if someone want to use it.

I'm sorry. English is not good at.
SFHSS Protocol is operating without problem in the laboratory test.

Operation check receiver
FUTABA R2106GF
OrangeRX SF700S 8 pieces
OrangeRX SF400S 5 pieces
Two COOLTECH RSF08SB
XK k120

However connected to all of the receiver If you do not adjust the FSCTRL0 could not.
Where I was confirmed FSCTRL0 = is 0x19 was good.

It is hope. Adding a fail-safe function to CH3.

Hi everyone,

Is there any way to modify the D/R of the 6G mode without modifying the 3G mode? with the original transmitter is quite easier to fly the heli on my living room . I tried to modify some curves on AIL and ELE but this also affect when flying 3G mode.

Thank you

I don't have one and haven't looked at the model file, but unless something is really odd, it should be straightforward. In the advanced GUI, of course, In the standard one, you're SOL.

The odd thing would be that you don't have a channel or switch to go between 3G and 6G modes. If you do, then you can use that same switch to change rates in on the cyclic channels. The question is then how do you want it to act? Lots of options here.

If you already have a D/R set up you like on a different switch and 3G to also turn on low rates, then set up a virtual channel that uses your current switch as a source in the first mixer, and the second is a fixed curve with a scale of low rates and use the 3G switch to enable it. Now use this channel as your D/R switch on the cyclic channels.

If you have a D/R switch that you want to work in 3G mode but with lower values, then add a mixer at the end of each cyclic that is enabled by the 3G switch with a fixed curve and your desired scale along with a mux type of mul. That will scale the current values whenever you throw the 3G switch.

If you don't have a D/R switch, then you can add a mixer at the end of each cyclic channel that is enabled by the 3G switch and gives you the low rate curve you want. In 6G mode, it won't be on.

When can a Futaba compatible receiver FASST mode be? Look forward to!

I seriously doubt it will happen at all. You never know, but FASST is not implemented (at least TX) by anyone beyond Futaba itself, and their original equipment is prohibitively expensive. People doing the reverse engineering (me included) buy the equipment with their own money. I can't justify buying $600 of stuff I will not use after I'm done with reversing it. I bought XK and Orange S-FHSS receiver because they're relatively inexpensive. They're collecting dust now

Also technically it's not that easy - Futaba uses different approach to radio than anybody else on the market. They started moving to 2.4GHz early, circa 2001 (as they claim at their site), there were not many consumer grade radio chips then. Now everybody uses chips initially intended for wireless keyboard or mouse. Then they were not invented yet. So they used separate radio front end and custom base-band processor. In theory, it is doable as well, and maybe we can emulate it with currently available chips already supported by Deviation. But it's a real research project - if someone would fund it, I'd definitely try.

On the other hand, T-FHSS is totally another matter - I plan to do it. I lack sensors for telemetry, but we can see, maybe public effort of reverse engineering SBUS2 can supply me with reasonable substitutes.

FASST uses RF chipset, ML2724
It is not very commonly used and pretty old, likely Futaba moves away from that and now uses cc2500, for commercial reasons like price and availability obsolescence of ML2724?
No other manufacturer uses that chip.

Definitely if (huge if) we support it someday we're not going to put ML2724, or more modern ML2730 in our set of RF modules. Besides, it's not enough - ML chips are just radio front end, they only modulate/demodulate signal, ML2730 can also recover data clock. To use them requires what is called base-band processor - device which when receiving clocks the signal and forms bit stream from raw demodulated signal, puts bits into bytes, checks the address, calculates and verifies checksum, and when transmitting doing the opposite operations. I believe modern processors can do these tasks fast enough. Futaba uses custom chip for this, FrSky receivers use FPGA for most intensive operations.

What is the difference between FHSS and SFHSS?

I have an old radiolink T6EHP it is marked FHSS on the case and uses a CC2500 with PA inside. I wonder deviation with the SFHSS protocol can take over my existing radiolink RXs. The problem with the old TX is that it may lose its configuration on glitching the power switch. I am ordering an analyser, a devo 10 and 2 CC2500 modules. I'll try when they arrive.

FHSS is a radio industry abbreviation meaning Frequency Hopping Spread Spectrum. S-FHSS is a particular Futaba protocol using the technique, thus the name. Futaba also has just FHSS, T-FHSS, and T-FHSS Air, which are all different protocols. They all have absolutely no relation to other people's "FHSSs", unless it is written "Futaba S-FHSS compatible" as in the case with XK.

Radiolink T6EHP is most probably have no compatibility with S-FHSS at all. What I would do is open the receiver - just take off plastic cover - and make detailed photos of both sides of the board with legible signs on the chips. Put the photos at some site allowing hi-res photos (this forum is not one of such sites) and post links here. It allows at least to estimate the efforts on reverse engineering it.

Also I'd suggest opening a thread in Protocols, not here in the Builds.

will this protocol work with the new xk x100? I believe it uses the same protocol as the xk x350 and of course the rf chip is a cc2500

The main chip on the Radiolink RXs is not marked. Other than that the RX has a CC2500 RF module and an ID setting switch. I'll see what we can do when my logic analyzer and CC2500 RF modules arrive.

Thanks.

@wasp09 can you publish a photo near radio chip?

@HappyHarry it should. As far as I understand it is supported by the same TX as XK K110/K120, so it uses S-FHSS.

@HappyHarry - not the same transmitter on the picture, but explicitly written on Banggood page: "Compatible FUTABA S-FHSS communication protocol."
www.banggood.com/XK-X100-With-3D-6G-Mode...d-RTF-p-1039066.html

thanks for the info, i did read that on BG's page, but they have been wrong with their information before so i thought i'd ask to be sure lol, it's a pity as i was hoping to finally get to use my logic analyser

There are many targets yet Chinese industry relentlessly produces new models with homebrewed protocols.