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Posted by midelic | Jan 09, 2017 @ 10:01 AM | 4,177 Views
DIY "FrSkyRX-USB" wireless RC dongle for model simulators

This is a wireless dongle for simulators with FrskyRX integrated.To be used directly with TARANIS,or TURNIGY9X/9XR/9XR+ ,togheter with DHT/DJT/XJT module or multimodule TX /DEVOTX.
The project is very easy one. Flashing the firmware is simple, using it is the same.

Atm I tested with FPVFreerider simulator working like a charm.

1.CC2500 Rf module
2.Any setup with Atmega 8/16Mhz
3.X-tal 16Mhz(or ceramic resonators like Murata 16 Mhz))
4.Diodes(1N4148) -2pcs
5.Resistor 68 Ohm -2 pcs
6.Capacitor 10uF-1pcs
7,Capacitor 100nF-1pcs
8.Resistor 1.5K
9.Resistor 1K

FUSEH = 0xc0
FUSEL = 0x9f

1.First you need to flash Atmega8 with bootloader file using a 3.3V USBASP programmer.Use only 3.3V recommended one (black PCB)NOT 5V).
2.With the jumper installed insert the dongle on USB port. Run the utility attached " HIDBootFlash"and press "Find Device".It will open a browse menu to find the FrskyRX_USB dongle firmware.Press Flash and wait for complete.

You can skip using the bootloader and flash directly dongle,firmware with USBASP programmer.But the subsequent flashing you need to do the same way using programmer.Bootloader has the advantage to flash directly via USB without any programmer.


1.Remove the flashing jumper.
2.With the bind button pressed insert the dongle on the USB port.The LED will come on.Prepare the TX for binding, start TX with bind button pressed.
The led on FrskyRX_USB dongle with flash slowly,...bind complete.
3.Remove the dongle and insert it again.The led will flash rapidly.Start TX normally dongle LED wil come on..TX and RX are bound.


See attached files.
The pcb posted in attachment were provided by "Joao" so I thank him for that.

If you like this project and you feel like to contribute with a paypal donation you can do at

Posted by midelic | May 10, 2016 @ 05:06 AM | 7,582 Views
I opened this thread to gather the best ideas and in order to design a better 2.4Ghz RF protocol with new features or improved ones that the other existing Rf protocols don't have.
So I suggest we start discussion from general to particular.From what we want to how we do it.
I will post on this first page all good ideas.
Crazy ideas are welcomed.

To summarize ideas until this moment.

1.To be opensource.
2.Maximum 24 channels.
3.RF chip 2.4Ghz CC2500.One of the most versatile 2.4GHz RF chip.
4.2.4Ghz generic protocol based on above chip with user configurable RF/protocol variables as data rate,no. of channels, bandwidth,update time interval,aso.This one may came with a configuration gui which can generate an user config file before compiling.
5.No PPM .To be used high speed serial comm >=100K between tx and TX RF module.Proposed serial SBUS 100K8E2 every 7ms,Maybe we can make configurable also this serial comm,change baud rate, update time,and/or no.of channels ,other data.This mod requires changes in TX firmware.
6 RX HW with PA/LNA and diversity.RX output serial SBUS .SUMD,or other serial protocol or all configurable.
7.RX with Telemetry.To be discussed if new Telemetry protocol,exiting one or modified.If possible the RX telemetry and serial output on the same port.
Posted by midelic | Jan 15, 2015 @ 11:05 AM | 19,827 Views
Lately I saw interest from some users regarding Flysky rx on Attiny85/45.
It looks like the old thread for rx is dead and large most of the info there was lost inside.
So I decided to make new diagram and post the code here on my blog.
Attached are 2 hex files one for Attiny85 and one for Attiny45.
See below.
XL7105-SY orCL
Attiny85/45(not tested on 45 yet) SMD
1K resistor(SMD 805)
LED-SMD size and color(603 or 805)
CAP-0.1uF(100nf)(SMD 603 or 805)
DIODE-1n4148 or other SI diode(or optional LDO)
Lipo-4.2V(if using 5V power supply need ldo voltage regulator or 2 diodes 1N4148 in series with LIpo positive wire)
If using ldo voltage regulator, there are very small ldo(same size like a SMD transistor for example MCP1700(CS(3.3V)))
The consumption is very low around 20mA.



Added some info for how to make this setup dead bug style to keep the weight down.See some pics from old thread.
Added also my pics with setup used.,,weight around 2.9g with wires,connectors,shrink tubing,and all.If using CL version the weight drops considerably.Between SY and CL version there is a weight difference of 0.7 grams.
Added also pics showing a SOIC8-DIP adaptor for flashing Attiny chip.
Added a version for 16Mhz.
Fuses for 16mhz
ATtiny85 16Mhz BOD 2.7V.


...Continue Reading
Posted by midelic | Jun 28, 2014 @ 11:43 PM | 11,077 Views
DIY Multiprotocol TX Module
This setup is based on Phracturedblue idea of universal Tx module he made for integration with his devo TX(deviation firmware).Following this and multiple RC protocols existing in deviation firmware,I was able to make an integration of these most popular RC protocols in arduino on a standalone module based on single atmel 328 chip and driven by any TX able to output PPM signal.
Protocol selection is made by using a dip switch or rotary dip switch (binary code).
More info below....
Posted by midelic | Mar 17, 2014 @ 02:30 PM | 10,926 Views
DIY FrSky TX(RF)Module
A DIY Frsky RF module based on Phracturedblue work in its deviation firmare.
I managed to port his deviation code for a DIY Frsky TX module in arduino.
For more info see:

The second post on the same thread
DIY FrSky RX module(2 way)
The code is an arduino adaptation from Kyrre Aalerud(aka Kreature)..frsky rx demo.
I tried his demo code as it was but unfortunately I couldn't make it work ,so I rewrote some parts of it..and added some more.Now It is complete with 8 channels servo PWM and PPM out signal,auto tunning routine for base channel offset...diagram.
For more info see:
Posted by midelic | Mar 05, 2014 @ 06:54 PM | 32,967 Views
I made Tx code for a single stick controller in a Nunchuck case...wireless(RF module inside).
The TX core is an Atmega 328 chip.It can be used an arduino promini board.
There are 2 versions one with separate acc using 6050 chip(gyro-acc combo) and other using original acc from wii nunchuck..Atm the RF module is an A7105 chip so it can work with Flysky and Hubsan protocol.
This version is using nunchuck acc sensor,,,for control.

If using other RF module can be programmed for use with other protocols.
If you are interested about more info you can ask directly on below thread.
Before start the setup need calibration.

default rate is 60%

-up_button(C button) 100% rate
-down_button(Z button) back on default rate.
The dual rate is set to default to 60%,..... for 100% push nunchuck "C"button and to revert to default 60% push "Z"button.

Calibration mode:
keep up_button "C" pressed and start the tx(switch)..you'll see led blinking..depress up_button "C" move stick up/down left/right to the end,when finished press down_button." Z".led comes solid on and calibration is complete."
************************************************** ****************************
Throttle/aileron are on nunchuck acc sensor...and rudder/elevator on single stick.It works following hand movement up/down on throttle(hand down throttle low,hand up raise throttle),left /right aileron movement(lean hand left...Continue Reading
Posted by midelic | Mar 05, 2014 @ 06:22 PM | 10,304 Views
DIY "FlySkyRX-USB" wireless RC dongle for model simulators

It was brought to my attention an old project PPM to USB adapter.
by Thomas Pfeifer on http://thomaspfeifer.net/ppm2usb_adapter_en.htm
This PPM to USB adapter was used as USB joystick for free RC simulators.Basically any TX with PPM out was hooked to this USB decoder..connected tor PC..and doing RC training on flight simulator.
Furthermore on DIY Flysky thread "plane spotter" was using a DIY Flysksy rx(in PPM mode) and togheter with a PPM to USB decoder(with pic chip)...trained his kids using a free model simulator.

Starting from that,I had an idea.

read more on...
Posted by midelic | Jul 10, 2013 @ 03:42 PM | 10,915 Views
As promised I made my hand ..on one Hubsan RF module.So finally arrived.I know there is already one version on openrc forum..but this one is here on Rcgroups.
Thanks to Phracturedblue brilliant work on hacking Hubsan protocol..., I was able to write an arduino code for a DIY Hubsan Tx module.
With this hardware posted below and this code I think it is possible for anybody to build his own Hubsan Tx module.
Because any serious tx have PPM output signal on trainer port(or more, like 9x for connect external module),
....I used Hasi's "Read_any_PPM" decoder for getting the required servo timing data.
read more on:

As some people request I made also an Hubsan Rx .Not all Hubsan flight controler but only Rx part.Atm it can be used in many aplications like multiwii setup using Hubsan ppm code....or FPV quad using Hubsan FPV tx.
more info below.
Posted by midelic | Jul 06, 2013 @ 08:49 AM | 12,219 Views
Well I made a multiwii 2.2 version with FlySky Rx integrated...meaning multiiwii with Rx in direct connection.......no servo signal, no PPM signal required,The FlySky rx code is integrated in multiwii code.At the moment this version was tested successfully by Phil Cowzer (Sadsack).He made also some videos.
However multiiwii -Flysky version is still in testing not yet final....
see below ....last version....


FlySky Protocol Integrated into Multi Wii Plus V4.3 Flight Test. (3 min 39 sec)

Posted by midelic | Jul 06, 2013 @ 07:40 AM | 11,411 Views
Inspired of the same PB,... Flysky protocol breakthrough...I wrote an arduino RX FlySky code...basically this code is written for multiwii integration,...... so it is not complete full Rx...but this will change in the future...see below link....
So this one it is still in development.Phil already tested one version Rx with PPM out and that will be posted soon....
More info will follow ...on these threads/posts
Posted by midelic | Jun 28, 2013 @ 01:43 PM | 11,991 Views
DIY "FlySky" TX/RX module

Thanks to Phracturedblue brilliant work on hacking Flysky protocol...and to ThierryRC excellent pic asm code, I was able to write an arduino code for a DIY FlySky Tx module.
With this hardware posted below and this code I think it is possible for anybody to build his own FlySky Tx module.
Because any serious TX have PPM output signal on trainer port(or more, like 9x for connect external module),
....I used Hasi's "Read_anyPPM" decoder for geting the required servo timing data.

See below some pics for an M8 arduino build by me used for testing Fkysky and Hubsan code.
read more about on: