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04 Jun 2020 17:27:04
Hello Six6siX
03 Jun 2020 13:28:30
ooo... hello all
02 Jun 2020 22:09:18
TBS Source One frame with 7" arms
02 Jun 2020 22:09:02
my guess was bang on the number - just out on the units!
02 Jun 2020 21:48:33
Just a bit out from your initial guess then  :laugh: What kind of frame do you fly with?
02 Jun 2020 18:52:22
shoutbox doesn't like ampersands for some reason
02 Jun 2020 18:51:54
and it was more like a 100m fall  :o
02 Jun 2020 18:50:36
lol - checked my logging
02 Jun 2020 11:52:29
@Liam - no, absolutely fine.  had another couple of flights with it afterwards -  :laugh:
01 Jun 2020 21:23:22
Ouch! Any breakages?
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OPENTX, FRSky & Taranis Info

Started by Fletch, Friday,December 30, 2016, 02:15:06

Previous topic - Next topic


Friday,December 30, 2016, 02:15:06 Last Edit: Friday,December 30, 2016, 03:18:45 by Fletch
This is a topic to gather the handy information on OpenTX, FRSKY and Taranis into one topic. 
I have put these three into one topic because they are so closely linked

All FrSky firmware downloads can be found here - http://www.frsky-rc.com/download/
Always use the latest download from the official site

Listed Below is -

FrSky EU Firmwares: Why, What & How
Flashing S.Port Devices through the Taranis with OpenTX 2.1
Taranis Telemetry -X-Series / Smartbus - FrSky - Modules & FAQ
Taranis Telemetry -X-Series / Smartbus - FrSky - Modules & FAQ (Continued)
OpenTX 2.1: A Basic Telemetry Tutorial for a Naze with Cleanflight
X4R SBUS/PPM Firmware
X4R Inverted/Non-Inverted Sbus signal


Friday,December 30, 2016, 02:16:31 #1 Last Edit: Friday,December 30, 2016, 03:15:52 by Fletch
Originally posted by Quadfather

This article has been updated on 04/01/16 to reflect the changes of the latest EU firmwares, and to correct some inaccuracies.

This is an attempt to shed some light on the pit of confusion that is FrSky';s EU firmwares for transmitters and receivers.  This article is stickied for reference.

If you';re familiar with flashing FrSky products jump straight to The crucial bit! and read on.

Why EU Firmwares?
FrSky';s X-type RF modules and D16 mode receivers were not compliant with the ETSI EN 300 328 v1.8.1 standard.  They issued a number of firmware updates since January 2015 in order to sell on the EU market.

The European Telecommunications Standards Institute (ETSI) has released a Harmonised European Standard for Wideband Transmission Systems operating in the 2.4 GHz band.  This standard has been adopted by the powers that be, and it';s now a legal requirement for sale in the EU that all devices falling into this category are certified.  That';s pretty much anything wireless we use on a daily basis, WiFi, Bluetooth, RC transmitters, etc.  If you have trouble going to sleep at night, here';s the standard for a quick path to the land of nod.

EU LBT Firmware
FrSky has released the Listen-Before-Talk (LBT) firmware for the EU X-series receivers and XJT modules.  These firmwares will be pre-installed on devices for the EU market from now on. 

FrSky highly recommends to upgrade to the LBT firmware as it fixes range and stability issues that some users have experienced with the EU firmwares released earlier this year.  You will need to flash all your X-series receivers and the XJT module to be compatible.

Note, flashing the LBT firmware to your XJT module will re-enable LR12 support, i.e. you can use the L9R receiver again.  The L9R receiver does not need a firmware upgrade.

If you';re buying new receivers in 2016 be aware that you will need to upgrade your XJT firmware to be compatible. For the uninitiated, the XJT module is the same as the internal RF module in the Taranis X9D, X9D+ and X9E radios.  Downgrading to an earlier EU version is not advised due to aforementioned issues.

Official announcement:

What RF module and what';s D16?
The RF module handles the communication to the receivers.  The Taranis has an internal XJT module, and external modules are available for use in other radios.  For the purpose of this article I will just refer to them as the XJT module.

The XJT module uses several protocols to talk to the receivers.  D16 is one of them, and it';s used for the X-range of receivers, i.e. X4R, X4R-SB, X6R and X8R.

There are two more protocols, D8 and LR12.  D8 is used for legacy receivers, those starting with D or V in their name, e.g. D4R-II, D8R-II+, V8FR-II, VD5M, etc.  Lastly, the LR12 protocol is for the long range receiver L9R.

What';s a firmware and why should I care?
In a nutshell firmware is software for embedded devices.  For example, Android and iOS on your mobile or the BIOS of your computer';s motherboard are types of firmware.

The Taranis has two firmwares.  One is the operating system (OS, i.e. graphics, controls, functions, etc), the other is for the RF (XJT) module.  These firmwares are independent of each other.  Updating the OS on your Taranis does not update the XJT module, and vice versa.

If you have a pre-2015 Taranis and buy new D16 mode receivers manufactured for sale in the EU, you wouldn';t be able to use them.  You can';t just update the OS to the latest version and expect it to bind with your new receivers.

It';s important to understand the difference between the two firmwares.  There is plenty of Internet chaff simply referring to "radio firmware" and such, when they mean one or the other, or don';t know that there is a difference.

The operating system is indirectly affected by the legislation, i.e. selection of the protocols in the model setup.  To the best of my knowledge, this is the only difference between the EU and non-EU operating systems.

The crucial bit!
This is important, your XJT module and any D16 receivers must match.  Either both have EU firmwares, or both have non-EU firmwares.  The D8 and LR12 mode receivers are not affected by this choice.  If you';re sticking with EU firmwares, then make sure to upgrade both the XJT and D16 receivers to the LBT firmware.  The latest LBT firmware fixes some issues present in older EU firmwares.

How do I make it all work?
The simplest solution is to update your stock Taranis firmware to the latest OpenTX 2.1 branch without ticking the EU box in the Companion settings.  OpenTX 2.0, while stable, is no longer developed.

The reason for this is that, despite FrSky';s claim to have dropped D8 and LR12 modes from the EU firmware for the RF module, these modes actually still work.  They were merely omitted from the mode selection in the operating system.  The same is true if you have installed OpenTX with the EU option enabled.

I';m giving a couple of scenarios for likely combinations of old and new devices that you may have.  Check the sticker in the module bay, it should tell you if your Taranis is an EU model or not.

For the EU Taranis with old and new receivers:
* Install the latest OpenTX firmware and do not enable EU-mode.  You will be able to use all receivers types.
* If you also have D16 mode receivers from before 2015 make sure to update them to EU firmwares.
* The LBT firmware is recommended at this point.

Options for pre-2015 or non-EU Taranis with old and new receivers:
A. Upgrade any new D16 mode receivers to the last non-EU firmware, or
B. Buy an external EU XJT module for new D16 mode receivers, or
C. Upgrade the internal XJT module to the current EU version, and
  1. Install the latest OpenTX firmware and do not enable EU-mode, and
  2. Upgrade any old D16 mode receivers to match

FrSky Receivers
D8 Mode
* D4R-II
* D6FR
* D8R-II plus
* D8R-XP
* Delta-8
* V8R4-II
* V8R7-II
* V8R7-SP
* VD5M

D16 Mode
* X4R
* X4R-SB
* X6R
* X8R

LR12 Mode
* L9R

FrSky Radio Modules
* XJT (D8, D16 & LR12 modes, internal for Taranis, JR-type external module for other radios)
* XFT (External XJT module to fit Futaba radios)
* DJT (D8 legacy protocols only, JR-type external module)
* DHT ("Hack" module, D8 legacy protocols only)

The future...
In 2014 the EU has quietly passed a directive preventing users from flashing non-compliant firmwares to their wireless devices.  This seems mostly aimed at people flashing their routers, but we may well get dragged into this.  This will take effect in June 2016.

A firmware upgrade tutorial
Flashing S.Port Devices through the Taranis with OpenTX 2.1


Originally posted by Quadfather

One of the many new improvements of OpenTX 2.1 is flashing external (and internal) modules directly from the radio.  In this example I have flashed my X4R-SB with the new CPPM beta firmware.

A word of warning

The voltage pin in the module bay puts out the battery voltage.  If you';re using a non-standard battery, e.g. a 3S LiPo, then make sure the device you flash can handle this voltage.  The standard battery will be fine.

What you';ll need

* OpenTX v2.1.x on your Taranis
* A firmware to flash (.frk file extension, .bin is not recognised or supported)
* An S.Port device (unless you flash the internal radio module)
* A custom cable if you';re flashing an S.Port device

S.Port pins are Signal-Positive-Ground (standard servo wire colour order).  The pins in the module bay are swapped, so we';ll need a custom cable.

The easiest way to make your custom cable is to use a servo extension lead and swap the ground and positive wires on the Taranis end.  For devices with different plugs (such as the X4R) you';ll need to be a bit more inventive.  Make sure to observe the correct pin order!

How to do it

Make sure your Taranis is sufficiently charged.  I';m not sure what happens to the device you';re flashing if the radio dies mid-flash.  The standalone FrSky firmware updater is known to brick devices if something goes wrong, this is probably no different!

  • Connect the Taranis in bootloader mode to your computer.  You should see two drives mounted, one is called Taranis (which we ignore) and the other is the internal SD card.

  • If you don';t already have one, create a directory called Firmwares on the SD card and place the .frk file(s) into it.  Strictly speaking you can name the directory whatever you like, but descriptive is best, IMO.

  • When you';re done transferring the file(s) safely remove (or unmount) the drives and turn off the Taranis.

  • If you';re flashing an external device plug it into the pins of the module bay now.

  • Turn on the Taranis.

  • Long press the Menu button to get into the Setup menu.  Press Page until you get to the SD Card browser.

  • Navigate to the Firmwares folder (or whichever you created) using the +/- buttons and press Enter.

  • Select the firmware file using the +/- buttons and press Enter.

  • Again using the +/- button select what you want to do, in my case Flash External Device, and press Enter.

  • A progress bar appears, and when it';s completed the device has been flashed.  You can then unplug it.

That';s it.  ~~


Originally posted by Jumpy07

The new X8R, (X6R, X4R), receiver that most people use with the Taranis has a new "Smartbus" port for a  new range of telemetry devices.. these are the sensors available so far.. 

PLEASE NOTE: To enable telemetry the X8R needs to be bound in D16 mode (mode 5)

Vario Sensor
There are two versions of this, high and low sensitivity. The High Sensitivity Vario can also be used as a gateway device to the old telemetry sensor hub and telemetry sensors. (The Data in and out ports connect to old telemetry Hub)


Lipo Voltage Sensor
1-6s, plugs into balance cable, at the moment you can only use one sensor,  but new firmware is in the wings to allow two sensors to be used at the same time.
Dimension: 35×23×6mm
Weight: 6g
Measurement range: 2S to 6S (6 to 25V)
Power consumption: 25mA@5V
Voltage display resolution: 0.01V
Voltage detection precision: 0.05V
Operating temperature: 10-70 degrees C
Pixel: 128 x 64 OLED Screen
Compatibility: FrSky Smart Port enabled receivers, such as X8R, X6R, X4R, etc.

*NB. Two x FLVSS connected via S.PORT can detect 12S voltages.


FrSky Smart Port to UART Converter w/2 ADC ports Remote
There are two versions of this.. one for the X8R and one for the XJT, the type B is for the X8R. This module also can be configured as an Analogue to Digital Converter.. so you can use the old style Voltage Sensors, these are just voltage dividers. This is the best way to get voltage monitoring working . . for APM users this could also be used to allow Mavlink telemetry to be shown on the Taranis, or to show GPS information etc..

Product Functions:
1. Serial port Data-Transmission at S.Port BUS.
2. Analog Signal AD input via S.Port.
Operational Voltage: DC 4 -10 V
Weight: 3g
Size: 44mmX15mmX7mm
Current Draw: 20mA @5V
Operating Temperature Range: -40 to 85C
UART Definition & Data-Transmission:
Baud Rate: 300 bps (default), 8N1, no parity.
The Baud Rate is possible to reconfiguration within 300bps, 600bps, 1200bps, 2400bps, 4800bps, 9600bps.
Capacity: Normal capacity (Mode 1) and High capacity (Mode 2)
To Enable Data-transmission at S.PORT BUS, the Host (Type A) and Remote (Type B) devices are requiring use as pair and set in same Capacity Mode.
Here we take the example by XJT module and X8R receiver to introduce how to Data-transmission at S.Port BUS:
- We definition the Host (Type A) is connect with XJT by S.Port, Remote (Type B) is connect with S.Port of X8R receiver.
(The Mode A and Mode B position is exchangeable)
- When input data from Type B UART port will output the same data at Type A UART port. Vice versa.
Obtain AD analog input via X8R & SP2UART adapter:
Because the X8R receiver does not have a built-in the AD port you cannot connect the simple voltage monitoring sensors directly to the X8R .. but now, you can, through this adapter.

Manual: [attachmini=1]



Smart Port Support Current Sensor40A FCS-40A - Current Sensor
Dimension: 61.2×16.7×13.2mm
Weight: 17g
Maximum battery voltage: 6S
Measurement range: 0~40A
Maximum safe current: 40A
Current consumption: 25mA@5V
Compatibility: FrSky Smart Port enabled receivers, such as X8R, X6R, X4R, etc.

GPS Sensor V2
Mode: GPS sensor (V2)
Interface: S.PORT
Operational Voltage: DC 4 -10 V
Weight: 11.3g
Current Draw: 80mA @5V
Sensitivity: -160dBm
Operating Temperature Range: -40 to 85C
Date Rate: 1Hz
Antenna: Built-in patch
Time to fix: 30s cold
Speed Accuracy: Approx 0.1m/s
Position Accuracy: Approx 2.5m CEP
Dimensions: 40 x 20 x 9mm (L x W x H)
Operation Limits: Dynamics 4g /Altitude 50,000m /Velocity 500m/s
Compatibility: FrSky Smart Port enabled receivers, such as X8R, X6R, X4R, etc.

The GPS should be mounted with Velcro in your model so that the "UP" side is facing toward the sky.

FrSky GPS Sensor (V2) - feeds variable directional information such as: Altitude, position, speed, and UTC time etc., which is displayed in real time on FrSky Transmitter or telemetry dashboard (DHT-U/FLD-02/FSD etc.)

NOTE: Each smart port telemetry device has an ID, when FrSky started releasing these devices there were changes to the default numbers assigned.
This is the list I have from current 2014 devices.
LIPO Sensors: 2
GPS: 4
Current Sensors: 3
Vario: 1

If you are using more than one lipo sensor you will have to change the ID of one of them, also if its running firmware prior to V1.2 you will have to update the firmware..


Originally posted by quadfather

If you have a Taranis or you';re using OpenTX then you may have heard of the recent OpenTX 2.1 release.  For any examples given below I';m using the latest version, which is v2.1.1 at time of writing.

The telemetry aspect of OpenTX 2.1 was redesigned from the ground up.  Unfortunately, this meant that any telemetry setups for v2.0.x models can';t be converted to v2.1.  While model conversion now works properly in v2.1.1 (there was a bug in v2.1 where trims were lost) anything related to telemetry will have to be set up from scratch.  These changes are also affecting Lua scripts and the SD card folder structure for scripts.  I';d go out on a limb and say that most people don';t use Lua so these changes don';t affect them, and it';s also beyond the scope of this tutorial.

For an OpenTX 2.1 telemetry preview have a look at this thread: http://openrcforums.com/forum/viewtopic.php?f=45&t=6887

I';m going to give an example for setting up telemetry in OpenTX v2.1.1 with an AcroNaze running Cleanflight and a D4R-II receiver.  It';s assuming a basic setup, with no other sensors.  However, any additional sensors will be just as easy to set up, for example current sensor, compass, GPS, baro, etc.  Consider a sensor any device that sends telemetry data.

The beauty of this new system is that it configures most of the telemetry for you.  It auto detects sensors from the telemetry stream and populates the model with all sensors it was able to identify.  If you add more sensors to your aircraft later, they will be picked up automatically.

Consider this new model I just created on the Taranis.  I bound the D4R-II and set up a flight mode switch, SC, and nothing else.  The RX is connected to the telemetry pins on the Naze.

If you flick to the telemetry page and your RX is powered on you';ll see this

"Where are all the other bits I used to have?" you say.  Arm the Naze and after a second or two you';ll see this

If you have your telemetry connected to a soft/serial port you should see the second image straight away.  The dedicated telemetry pins only send data when the board is armed.

These are all the telemetry sensors the Naze sends back at all times.  Since mine is an AcroNaze I don';t have a baro and compass, yet the telemetry sensors for it are there (Alt, Temp, Hdg).  You also see the Curr and GPS sensors, even though I don';t have them.  The reason for this is that the Naze acts as a virtual hub for sensors, and it emulates proper FrSky sensor IDs which are then detected by OpenTX.  BTW, Date refers to how long the Naze is armed for.  It doesn';t reset when you disarm, only when you power cycle.

You may notice the discrepancy between Cels and VFAS.  This is because they are calculated differently in Cleanflight.

I went ahead and measured my actual battery voltage with a DMM, which was 11.15V.  The VFAS sensor allows you to adjust the reported voltage, so this is the one I';m using, and I';m not going to bother with Cels.

Scroll down to the VFAS sensor.  Press and hold Enter until you get a pop-up menu, where you select Edit.  Navigate to Offset and change the value there until the VFAS output at the top matches what you measured earlier.

You could change the Name of this sensor here if you wanted.  PREC2 means it will show two decimal places, other options are PREC1, and PREC0 for integers.

Exit out of the VFAS screen and scroll down to Top Bar.  The top bar is what is shown at the top of the main screen, next to the Taranis'; own voltage.  Here you can select VFAS as Voltage Source.  If you have a Baro you can select it for Altitude, and it will show the height next to the voltages.  Unfortunately, my screenshot didn';t capture this, but I think you can abstract that much information.  If you don';t care for the top bar, simply skip this step.

Next is the telemetry screen setup.  OpenTX offers four screens and three display options.  These options are Nums, Bars or Lua scripts.  If you';re a scripter, this is where you set it up.  I went for just one screen with numerical values, and selected the following items

Obviously, you';ll select whatever you find useful.  Time is the Taranis'; internal clock.  I wouldn';t normally display accelerometer values, but I wanted something to populate the screen.  :tongue:

With the telemetry screen set up, press Exit until you';re back at the main screen.  Take a look at the top bar if you have set it earlier.

Press and hold Page and the Taranis will display the telemetry screen, which now looks like this

Once the telemetry sensors are populated you can use these in the custom functions as well, for example play an alarm when the voltage dips below a certain value, etc.

I hope you';ll find this useful, and it shows that the new telemetry system isn';t that complicated.  In fact, I find it easier than the old system.  It shouldn';t really matter what RX or flight controller you';re using, as long as the telemetry data sent is compatible with FrSky telemetry.

I';ll do another tutorial in the near future whitch will use the FLVSS voltage sensor and some GPS data extrapolation.



Friday,December 30, 2016, 02:55:13 #6 Last Edit: Friday,December 30, 2016, 03:18:00 by Fletch
FrSky have released a firmware for the X4R and X4R-SB which enables CPPM output.

This upgrade turns output 1 into 8-channel CPPM, with the rest of the outputs becoming additional PWM channels.  On the X4R-SB CPPM and SBUS are both available without the need of reflashing or jumpering any signal pins.


Flash the firmware with your preferred method, e.g. via FUC-3 or through Taranis. 

Binding without the jumper retains the original behaviour, i.e. PWM channels 1-4.
Binding with jumper turns output 1 into CPPM channels 1-8, the rest become PWM channels 9-11.

Binding without the jumper retains the original behaviour, i.e. PWM channels 1-3 and SBUS on output 4.
Binding with jumper turns output 1 into CPPM channels 1-8, outputs 2 & 3 become PWM channels 9 & 10, and output 4 is still SBUS.

Essentially this firmware turns the X4R into an 8+3-channel RX, and the X4R-SB into a 8+2/16-channel RX.

See first post for firmware links


Friday,December 30, 2016, 03:12:14 #7 Last Edit: Friday,December 30, 2016, 20:38:35 by Fletch
X4R Non-inverted SBUS signal

There isn';t much to this mod, you remove the case and pick up your sbus signal from the A pin in the image, and connect direct to the flight controller.

It has been suggested it may be a good idea to place a ~330Ohm resistor on the SBus signal line (there';s one in the original X4R circuit, after the inverter) to protect the RX.