DeviationTX with NRF24L01 module, the universal drone remote control.

The Walkera Devo TX with Deviation Open Source firmware and a NRF24 external module is simply an awesome piece of free software/machinery combo, akin to a universal drone remote control, or “drone-be-gone”.

One of the best kept secret of a Walkera transmitter is the ability of the built-in Cypress CY7C68013A chip to support  multiple RC hobby radio protocols such as the DSMX, DSM2 or DEVO. Just install the alternative Deviation firmware to unlock these modes. However the protocols used in cheap toy drone is normally based on a different chip , the cheap Nordic NRF24L01 and his clones. But thanks to the deviation developer community you just have to install a $5 module to support dozens of toy drones with a hobby/professional grade transmitter.

IMGP0534
You can save a lot of money buying cheap replacement toys quadcopters (BNF or Bind-And-Fly models)  instead of the full pack of drone with transmitter. For me this was a big deal, as having different transmitters is space consuming, time-consuming, battery consuming, and money consuming. The simplicity of using one quality radio is priceless, as most toy drone transmitters are crap quality toys modeled after console controllers instead of proper RC hobby transmitter.

Having an almost universal rc controller also allow to play practical jokes to friends hijacking almost any toy drone they have. Security in these protocols is nonexistent. Some older toy drones have fixed address IDs and do not use frequency hopping so the most powerful transmitter is able to hijack or at least interfere with the drone . The current implementation of NRF24L01+ tend to use random IDs and channel hopping and these are negotiated by binding drone and remote station on every startup. So if the victim turns the drone before the station there is a time window that allows the hijacking . You only need to bind your controller before theirs and fly away, original controller will be useless and not be able to prevent the drone escape!

Although there are several Devo TX models supported my personal recommendation here is the Devo 7e. The E is important because there is a Devo 7 not deviationTX compatible. Being one of the most common and least expensive Devo RC controllers there are plenty of hacks for this model. The size of the Devo 7e makes it very portable, yet it feels very solid in the hand.

You will need:

  • A Deviation supported Devo TX ( Devo 7e is under $60 )
  • 1 x nRF24L01 with external antenna connector or internal antenna ($5-$7)
  • Tools: In general, you will need a hex screwdriver to open controller, one good soldering iron with a thin tip, multiple color cables and some electrical tape to insolate the nrf24module.  Depending on the NRF24 module you choose , you can use the internal antenna built-in OK for indoor fly. Or you’ll have to drill a hole to a new external antenna for greater outdoor  range.

And at least one toy drone to play with, some recommendations:

X5C_BNF_8

Installation is as simple as soldering a small number of cables between the module and the station. You can find the nRF24L01 to Devo 7e pinout at

https://bitbucket.org/PhracturedBlue/deviation/wiki/Devo7eModuleInstall

 

hacksmods_Devo7e_v202_nRF24L01_deviationx_module_mod

Keep in mind, there are two locations you can connect the CSN (yellow) point to on the Devo7e. Either to TMS or TCK. If this will be the first addon module you install into your Devo7e, then connect to the TMS location. If there’s already a module installed, then you will use the second point: TCK.

devo7e-nRF24L01-module

After installation put your Devo 7e into USB mode, connect to computer and open up the drive. Locate hardware.ini (tx.ini on older firmware). Enable the newly installed module so that the radio recognize that the module has been installed remove the semicolon that proceeds the line to enable it.

If you installed to the TMS location your configuration file has to look like this .

enable-nrf24l01 = A13
has_pa-nrf24l01 = 1

 

If you have questions there a lot of additional guides on the internet,  SeByDocKy from rcgroups forum have a nice video tutorial on nRF24L01 install.

 

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