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I'm making some progress , I'm fairly confident it's almost there

Come on guys! More captures

Thanks, added to the list (#3), it follows the pattern

Please, take a look. I think this time I finished the bind process.

www.dropbox.com/s/8xclcd675x4msxe/CX-10%20Green2.rar?dl=0

Ok, I will try something....

Thanks, but no bind, no hopping sequence

(pas de bras, pas de chocolat )

A new capture from my almost destroyed CX-10 green TX
I don't now if you can extract some valid info, because can't complete the bind process without the sticks



Removed capture

This is what we have so far:
Seems only packet[1] and packet[2] has something to do with frequencies sequence,

That's not enough for me to crack it, but a pattern is starting to emerge
rf channel 1 = (packet[1] & 0x0F) + 0x03
rf channel 2 = (packet[1] >> 4) + 0x16
rf channel 3 = (packet[2] & 0x0F) + 0x2D
rf channel 4 = (packet[2] >> 4) + 0x40

we may have to make captures on the RX side with more TXIDs on TX side.

I captured SPI traces from my JXD 395 TX to bring some help to full reversing protocol:

www.dropbox.com/s/v7xq8d6pywl1nmd/JXD395.rar?dl=0

I'm back... at this point I've tested 4 nano sized quads with Deviation:

- Proto X
- Proto X SLT
- Cheerson CX-10 (red)
- WLToys v272

I hope this helps someone and saves them the money I blew

At this point in time, very reluctantly, I have to say that the WLToys v272 is my favorite nano sized quad for Deviation, despite it's low yaw rate. The main reason I would recommend the 272 is the price. The yaw rate is a bit slow but it's the only drawback, otherwise it flies really well and does nice flips, and flight times are close to 5 minutes. My old Proto X only gets about 3 minutes. The new Proto X SLT would be the king as far as I'm concerned, despite costing more then twice the 272, but there is an issue with Deviation and the SLT protocol right now that is preventing it from claiming the throne. The Cheerson CX-10 is great too, but building a red pcb deviation compatible one yourself is a huge pain since the parts are so tiny - it's harder then you'd think to cram it all together and it will cost you at least 2x what a v272 will cost you, so it's eliminated too.

At $15 (BNF) there really is no competition for the v272: It is the king of the Deviation-Compatible Nano Sized Quads.

goebish wrote: very interesting article: travisgoodspeed.blogspot.fr/2011/02/prom...-nrf24l01s-duty.html ... one more rss feed to follow.

Yeah, I know about Travis for a long time. He's an impressive guy. Check out Michael Ossmann, the author of HackRF and Ubertooth.

I still have high hopes for ADF7242 - it's a chip which supports many data rates, flexible modulation (you can vary frequency deviation) and it supports direct mode - it gives you just a stream of bits (you can ask for preamble and address detection if you want) and you're free to process them. The reverse is also true - it will encode your bit stream as you wish, no limitation on packet structure.

It requires some extra handling, effectively you need provide all buffering and packet structure yourself, but is much more flexible.

Their eval boards are expensive - $100 for a bare chip and some passives on a small PCB, otherwise I'd have ordered it long ago.

I really need to invest in a HackRF ... But I also want a Taranis... I've to make an hard choice
Thanks camousse, I didn't know the nrf24 has promiscuity mode, if this is the case I understand how this would be possible.

Sorry victzh, I'm not impatient, just very curious, I've to understand how things work or I can't sleep at night

edit:
very interesting article: travisgoodspeed.blogspot.fr/2011/02/prom...-nrf24l01s-duty.html ... one more rss feed to follow.

Ok i understand what you mean. Preambule (one bytes that is sent before address is sent, to identify start of packet) is different from nrf24l01 to xn297. this means the nrf never identify the start of a new packet, so we never receive what we expect.
Some guys try to put the NRF24L01 in "promiscous mode" (as in ethernet, listen to packet without knowing the address). I already post the link in the jxd395 thread.
The basic idea is that. Packet are composed of preambule, address, and payload. For exemple, preambule is AA. By using a address on 2 bytes (the minimum), and setting the address to AA AA, nrf24l01 will misunderstand the start of the packet, and the payload will be the real address.
Ok i think about it, and it isn't usefull as preambule is different

Patience...

^ That.

I understand how your TX code works, but I don't understand how it could work the other way'round if the nrf24l01 doesn't receive a valid preamble.

The main problem is not changing the mode, it can be done through the power down as PB said (more slowly, but may be not critical). The problem is whether nRF24 or Beken can detect a valid packet on air, issued by XN297. It's not tested yet, and not implemented in the emulation layer.

I analyse the blue board protocol on the past. And the tx have to receive the rx id to send good packet (only one).
The CE pin of the NRF24L01 is always high, so you can't change the mode (TX/RX of NRF24L01). But PB said it is possible by shutting it down, and restart it in RX mode. It take times (don"t remeber how much) but i think it can work

Awesome work!

I'm brand new to the scene. I recently purchased a CX-10 but I didn't like the controller so I purchased a Devo 7E. Of course I'll buy more serious copters later but for now, this is a neat toy.

victzh wrote: @Durete - it's as safe as any nightly build, your judgement here is as good as mine.

@magic_marty - it will, I just built it for the one I have (10) and another one that is critical with resources (7E) to check it compiles and works well with the module system. The module itself is not production quality yes, one thing is the protocol is not reversed fully yet and we can't support many CX-10 flying simultaneously. Another, I would like to implement "blue board" as well. It will take some time but it's gonna be soon.

I also have a blue board. I look forward to your work on that and it is much appreciated.