FrSky TANDEM X20 User manual

X20 and Ethos
User Manual

Table of Contents
Main Views.................................................................................................................................. 1
The Top Bar............................................................................................................................. 1
The Bottom Bar.......................................................................................................................1
The Widgets Area....................................................................................................................1
User Interface and Navigation.....................................................................................................2
Editing ontrols.......................................................................................................................2
Virtual Keyboard.................................................................................................................2
Number Value ontrols.......................................................................................................3
Options feature...................................................................................................................3
USB onnection To P modes....................................................................................................6
Power Off mode...................................................................................................................... 6
Bootloader mode.....................................................................................................................6
Power On mode......................................................................................................................6
Emergency Mode......................................................................................................................... 7
System Setup.............................................................................................................................. 8
Overview................................................................................................................................. 8
File Manager.......................................................................................................................8
Alerts..................................................................................................................................8
Date & Time........................................................................................................................8
General............................................................................................................................... 8
Battery................................................................................................................................ 8
Hardware............................................................................................................................8
Sticks.................................................................................................................................. 8
Wireless.............................................................................................................................. 8
Info..................................................................................................................................... 8
File Manager........................................................................................................................... 9
Alerts..................................................................................................................................... 13
Silent Mode heck............................................................................................................13
Main Battery heck..........................................................................................................13
RT Battery heck...........................................................................................................13
Inactivity............................................................................................................................13
Date and Time.......................................................................................................................14
24 Hour time.....................................................................................................................14
Display seconds...............................................................................................................14
Date.................................................................................................................................. 14
Time..................................................................................................................................14
Time Zone........................................................................................................................ 14
Adjust RT Speed............................................................................................................ 14
Auto Adjust from GPS.......................................................................................................15
General................................................................................................................................. 16
Language.......................................................................................................................... 16
Display Attributes.............................................................................................................. 17
Audio Settings..................................................................................................................19
Vario................................................................................................................................. 20
Haptic............................................................................................................................... 20
Top Toolbar....................................................................................................................... 21
Battery................................................................................................................................... 22
Main Voltage.....................................................................................................................22
Low Voltage...................................................................................................................... 22
Display voltage range.......................................................................................................22
RT voltage...................................................................................................................... 23
Hardware.............................................................................................................................. 24

Hardware check................................................................................................................24
Analogs calibration...........................................................................................................25
Gyro calibration................................................................................................................25
Analogs Filter.................................................................................................................... 25
Pots/Sliders Settings.........................................................................................................26
Switches Settings.............................................................................................................26
Home Keymap..................................................................................................................27
AD value inspector......................................................................................................... 28
Sticks.................................................................................................................................... 29
hannel Order..................................................................................................................29
First four channels fixed....................................................................................................30
Wireless................................................................................................................................ 31
Bluetooth Mode................................................................................................................31
Info........................................................................................................................................ 36
Firmware........................................................................................................................... 36
Firmware Version..............................................................................................................36
Date.................................................................................................................................. 36
Sticks................................................................................................................................ 36
Internal Module................................................................................................................. 36
Receiver........................................................................................................................... 37
External Module................................................................................................................37
Model Setup...............................................................................................................................38
Overview............................................................................................................................... 38
Model Select..................................................................................................................... 38
Edit Model......................................................................................................................... 38
Flight Modes.....................................................................................................................38
Mixer................................................................................................................................. 38
Outputs.............................................................................................................................38
Timers............................................................................................................................... 38
Trims.................................................................................................................................38
RF System........................................................................................................................ 39
Telemetry..........................................................................................................................39
hecklist........................................................................................................................... 39
Logic Switches..................................................................................................................39
Special Functions.............................................................................................................39
urves.............................................................................................................................. 39
Trainer..............................................................................................................................40
Device onfig...................................................................................................................40
Model Select......................................................................................................................... 41
Managing Model Folders..................................................................................................41
Adding a New Model.........................................................................................................43
Selecting a Model.............................................................................................................44
Edit model............................................................................................................................. 46
Name, Picture................................................................................................................... 46
Model Type....................................................................................................................... 46
hannel Assignments.......................................................................................................46
Function Switches............................................................................................................. 47
Persistent..........................................................................................................................47
Reset All Mixers................................................................................................................47
Flight Modes.......................................................................................................................... 48
Name................................................................................................................................49
Active ondition................................................................................................................ 49
Fade In, Out...................................................................................................................... 49
Trims.................................................................................................................................49
Flight Mode Management.................................................................................................50

Mixer..................................................................................................................................... 51
Aileron, Elevator, Rudder Mixer........................................................................................52
Throttle Mixer.................................................................................................................... 55
View per hannel option (mixer grouping)........................................................................58
Predefined Mixes..............................................................................................................61
Outputs................................................................................................................................. 70
Outputs Setup...................................................................................................................71
Timers................................................................................................................................... 73
Name................................................................................................................................74
Mode................................................................................................................................ 74
Alarm/Start Value..............................................................................................................74
Sound............................................................................................................................... 74
Haptic............................................................................................................................... 74
ountdown Start...............................................................................................................74
ountdown Step...............................................................................................................74
Timer Elapsed Audio File..................................................................................................74
Active ondition................................................................................................................ 75
Reset................................................................................................................................ 76
Persistent..........................................................................................................................76
Trims..................................................................................................................................... 77
Trim Mode........................................................................................................................ 77
Extended Trims.................................................................................................................78
Independent Trim per Flight Mode....................................................................................78
ross Trim........................................................................................................................ 78
RF System............................................................................................................................ 79
Owner Registration ID......................................................................................................79
Internal Module................................................................................................................. 79
External Module..............................................................................................................108
Telemetry............................................................................................................................. 111
Smart Port telemetry.......................................................................................................111
FBUS control and telemetry............................................................................................113
Telemetry features in A ESS.......................................................................................113
Telemetry Settings..........................................................................................................116
hecklist..............................................................................................................................127
Throttle heck................................................................................................................127
Failsafe heck................................................................................................................127
Pots / Sliders heck.......................................................................................................128
Switches heck..............................................................................................................128
Function Switches heck................................................................................................129
Logic Switches....................................................................................................................130
Adding Logic Switches....................................................................................................131
Logic Switches – Shared Parameters.............................................................................137
Option to Ignore Trainer Input.........................................................................................138
Logic Switches – Use with Telemetry..............................................................................138
Special Functions................................................................................................................139
Special Functions...........................................................................................................140
urves................................................................................................................................. 146
Expo............................................................................................................................... 147
Function.......................................................................................................................... 147
ustom...........................................................................................................................150
Trainer.................................................................................................................................152
Trainer Mode = Master...................................................................................................152
Trainer Mode = Slave.....................................................................................................156
Device onfig...................................................................................................................... 157
onfigure Screens...................................................................................................................158

onfiguring the main screen................................................................................................159
Adding additional screens...................................................................................................160
Adding ustom Widgets......................................................................................................161
Lua Scripts...............................................................................................................................162
ETHOS Lua Interpreter.......................................................................................................162
ETHOS Lua Documentation................................................................................................162
ETHOS Lua Example Script Files Location.........................................................................162
Lua Scripting onfiguration Limits.......................................................................................162
Basic Layout of a Lua Widget..............................................................................................163
key (string)......................................................................................................................163
name (string or function).................................................................................................163
create (function)..............................................................................................................163
configure (function).........................................................................................................163
wakeup (function)...........................................................................................................163
event (function)...............................................................................................................163
paint (function)................................................................................................................163
read (function)................................................................................................................163
write (function)................................................................................................................163
Programming Tutorials.............................................................................................................164
Initial radio setup example...................................................................................................164
Step 1. harge the radio and flight batteries...................................................................164
Step 2. alibrate the hardware.......................................................................................164
Step 3. Perform the Radio System setup........................................................................164
Basic Fixed Wing Airplane example....................................................................................166
Step 1. onfirm System settings.....................................................................................166
Step 2. Identify the servos/channels required.................................................................166
Step 3. reate a new model...........................................................................................166
Step 4. Review and configure the mixes.........................................................................169
Step 5. onfigure the Outputs........................................................................................174
Step 6. Introduction to Flight Modes...............................................................................177
Step 7. Set up a flight battery timer.................................................................................178
Step 8. Add a mix for retracts..........................................................................................179
Basic Flying Wing (Elevon) Airplane example.....................................................................180
Step 1. onfirm System settings.....................................................................................180
Step 2. Identify the servos/channels required.................................................................180
Step 3. reate a new model...........................................................................................180
Step 4. Review and configure the mixes.........................................................................182
Step 5. Review the Mixes...............................................................................................184
Step 6. onfigure the maximum servo throws................................................................185
Basic Flybarless Helicopter example...................................................................................186
Step 1. onfirm System settings.....................................................................................186
Step 2. Identify the servos/channels required.................................................................186
Step 3. reate a new model...........................................................................................186
Step 4. Review and configure the mixes.........................................................................188
Step 5. FBL Setup..........................................................................................................192
'How To' section................................................................................................................... 193
1. How to set up a low battery voltage warning...............................................................193
2. How to set up a battery capacity warning using a Neuron ES ..................................196
3. How to set up a battery capacity warning using a calculated sensor..........................198
4. How to create a model for SR8/SR10.........................................................................201
5. How to reorder channels e.g. for SR8/SR10...............................................................202
6. How to configure a Butterfly (aka row) mix...............................................................205
7. How to configure an FBUS system.............................................................................212
Ethos Suite.............................................................................................................................. 219
Overview.............................................................................................................................219

Procedure for migrating to Ethos Suite................................................................................219
Operation............................................................................................................................ 221
Welcome Section............................................................................................................221
Radio Section.................................................................................................................222
Tools Section..................................................................................................................228
Others Section................................................................................................................231
DFU Mode...................................................................................................................... 233

X20/X20S and Ethos v1.2.10 User Manual
Main Views
Ethos allows the user considerable flexibility in what is displayed in the Main iews. Initially
only the basic information shown below is displayed, until the user customizes or adds views
and widgets to be displayed. Note that up to eight Main iews may be defined.
The Main iews normally share the top and bottom bars, but there is a full screen option.
Please refer to the Configure Screens section for details on configuring the views.
The Top Bar
The top bar displays the model name on the left, as well as the active Flight Mode if
configured. On the right are icons for:
•Whether data logging is active
•Trainer icon for Master or Slave as appropriate
•RSSI 2.4G
•RSSI 900MHz
•Speaker sound volume
•Radio battery status
Touching the speaker and battery icons will bring up the relevant General (Audio etc.) and
Battery control panels.
The Bottom Bar
The bottom bar has four tabs for accessing the top level functions, i.e from left to right: Home,
Model Setup, Configure Screens, and System Setup. The system time is displayed on the right.
Touching the time will bring up the Date & Time settings.
The Widgets Area
The middle area of the Main iews consists of widgets which may be configured to display
images, timers, telemetry data, radio values etc. The default main screen has a widget on the
left for a model image and three widgets for timers, as well as displaying the trims and pots.
The widgets are user configurable to display other information. Once multiple screens have
been configured, they can be accessed using a touch swipe gesture or navigation controls.
Please refer to the Configure Screens section for more details.
Note: The ‘Throttle ACTI E’ widget above is the Status widget available in the FrSky - ETHOS
Lua Script Programming thread on rcgroups.
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User Interface and Navigation
The X20/X20S has a touch screen, making the user interface quite intuitive. Touching the
Model Setup (Airplane icon), Configure Screens (Multiple Screens icon), and System Setup
(Gear icon) tabs take you directly to those functions, which are described in those sections of
the manual. They can also be accessed using the [MDL], [DISP] and [SYS] keys respectively.
A long press on the [RTN] key will return you to the Home screen from any sub-menu.
Touching the system time on the right of the bottom bar takes you to the Date & Time section,
allowing you to set the time and date.
Touching the speaker or battery icons in the top bar will bring up the relevant Sound & ibr.
and Battery control panels.
Editing Controls
Virtual Keyboard
Ethos provides a virtual keyboard for editing text fields.
Simply touch on any text field (or click [ENT]) to bring up the keyboard.
Touch the '?123' or 'abc' key to toggle between alpha and numeric keypads. There is also a
Caps lock for entering uppercase letters.
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Number Value Controls
When touching a Number alue a dialog pops up with keys for setting the value to Min,
Default or Max, and also 'plus' and 'minus' keys for incrementing or decrementing the value.
In addition, the slider across the bottom allows for the rotary encoder output per click to be
adjusted from 1:1 or fine on the left, and coarse on the right. The slider may also be
adjusted with the rotary encoder while the [Page] key is held down.
Another example is a Telemetry Range value, which can be edited in a similar way.
Options feature
Ethos has a very powerful 'Options' feature. Almost anywhere a value or source is expected,
a long press of the Enter key will bring up an Options dialog.
Fields with this feature can be identified by the square dot in the top left corner of the field.
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Value options
The alue Options dialog shows which parameter is being configured. In this example
you have the choice of setting the Weight/Rates to maximum or minimum, or to use a
source. Using a source like a Pot would allow the Weight/Rates to be adjusted in flight.
If you click on a alue field that has already been changed to use a source, a dialog pops
up allowing you to convert the source's current value to a fixed value. Clicking on
'Options' will bring up options for the source, see below.
Source Options
Invert
Invert allows a source such as a switch position to be negated or inverted. For
example instead of being active when switch SA is up, it would be active when switch
SA is NOT up, i.e. in either the mid or down positions.
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Edge
You can select the 'Edge' option if you need a one-time action when the source
transitions from False to True or from True to False. Only the transition is acted upon,
not the True or False state.
Please refer to the X20 and Ethos thread on rcgroups.com for more details and
discussion on the use of this new feature.
Ignore Trainer Input
In Logic Switches the sources may have this option set to ignore sources coming from
the trainer input. A typical application is where a logic switch is configured to detect
movement of the master trainer’s sticks (e.g. Elevator stick) to allow for instant
intervention if things go wrong. This option is needed to prevent the student stick
inputs from triggering the logic switch.
Sensor Options
On a Telemetry source the Options dialog allows the sensor to be inverted, or its
maximum or minimum value to be used. Some sensors have additional options specific to
that sensor.
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USB Connection To C modes
Power Off mode
•Connecting the X20 while powered off to a PC via a USB cable is the DFU mode for flashing
the bootloader.
Bootloader mode
•The X20 is placed in bootloader mode by switching on the radio with the enter key held
down. The status message ‘Bootloader’ will be displayed on the screen.
•The radio can then be connected to a PC via a USB data cable. The status message will
change to ‘USB Plugged’, and the PC should display two external drives connected. The first
is for the X20 flash memory, and the second is the content of the SD card.
•This mode is used for reading and writing files to SD card and/or the X20 flash memory.
Power On mode
•If the radio is connected to a PC via a USB data cable while powered on, the following option
dialog is displayed:
•In joystick mode the radio can be configured for controlling RC simulators.
•In Frsky Suite mode the radio will enter ‘Ethos Mode’ for communication with Ethos Suite.
Please refer to Ethos Mode in the Ethos Suite section.
•In Serial mode Lua debug traces are sent to USB-Serial if present. The baud rate is
115200bps. A suitable Windows irtual COM Port driver may be found here.
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Emergency Mode
Emergency Mode is the radio’s response to an unexpected event like a watchdog reset. The
watchdog is a timer that is continually restarted by different parts of Ethos. If a failure of any
kind prevents the watchdog timer from being restarted, it will time out and cause a hardware
reset of the radio. In this Emergency Mode the radio restarts extremely quickly, without any of
the normal startup checks so that you get back control of your model as quickly as possible.
The SD Card is not accessed in Emergency Mode.
Emergency Mode provides only the essential functions for controlling your model but none of
the high level functions. The screen will go blank and display the words Emergency Mode,
accompanied by a 300ms beep repeating continually every 3 seconds. oice alerts, running of
scripts, logging etc. will cease operating. If Emergency mode occurs, you should obviously land
as quickly as possible.
The most common cause of Emergency Mode is SD Card failure.
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System Setup
The System setup menu is used to configure those parts of the radio system’s hardware that
are common to all models, and is accessed by selecting the Gear tab along the bottom of the
screen. Conversely, model specific setup is performed in the Model menu, which is accessed by
selecting the Airplane tab along the bottom of the screen.
Please note that the settings to determine whether the internal or external RF module is used
are model specific, so these are handled in the ‘RF system’ section of the Model menu.
Overview
File Manager
The File Manager is for managing files and for access to flash firmware to the TD-ISRM,
external S.Port, OTA and external modules.
lerts
Configuration of the silent mode, battery and inactivity alerts.
Date & Time
Configuration of the system clock and time display options.
General
For configuring the menu style, system language, and LCD Display attributes such as
brightness and backlight, as well as Audio, ario and Haptic modes and stings.
Battery
Configuration of battery management settings.
Hardware
This section allows checking of the hardware physical input devices, and analogs and gyro
calibration. It also allows the switch type definitions to be changed.
Sticks
Configuration of the Stick Mode, and the default channel order. The 4 stick controls can also
be renamed.
Wireless
Configuration of the Bluetooth module.
Info
System information for firmware version, gimbals types and RF modules.
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File Manager
The File Manager is for managing files and access to flash firmware to the TD-ISRM,
external S.Port, OTA and external modules.
Note that when updating the system firmware, the files in the flash drive and SD card may
also need updating.
Tap on File Manager to open the file explorer. The top level of folders are:
audio/
USB drive path: SD Card (drive letter)/audio/
This folder is for user sound files, which can be played by the 'Play track' Special
Function. Refer to the Model / Special Functions section. The format should be 16kHz or
32kHz PCM linear 16 bits or alaw (EU) 8 bits or mulaw (US) 8bits.
audio/en/system
USB drive path: SD Card (drive letter)/audio/en/system
This folder is for system sound files, e.g.
hello.wav The 'Welcome to Ethos' greeting
bye.wav This is not provided yet by Ethos, but you can add your own
goodbye WA file.
Tap on the [audio] folder to view the folder contents.
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Tap on a WA file, and select the Play option to listen to it.
The files may also be copied, moved or deleted.
bitmaps/models/
This folder is for user model images. The recommended image format is the following
BMP format:
32bits BMP format
8 bits per color
Alpha channel (used for image transparency)
Size: 300x280px
This format reduces the computational load on the on-board microcontroller of the X20.
Image file naming rules:
Rule 1: use only the following characters: A-Z, a-z, 0-9, ()!-_@#;[]+= and Space
Rule 2: the name must not contain more than 11 characters. If the name is longer
than 11 characters, it is displayed in the SD card explorer but does not appear in the
model image selection interface.
USB drive path: SD Card (drive letter)/bitmaps/models/ (note this folder was
bitmaps/user prior to Ethos 1.2.6)
Image conversion tools
There are some useful image conversion tools available:
1. Windows based
https://github.com/Ceeb182/ConvertToETHOSBMPformat
(This utility also applies the file naming rules.)
. Web based
https://ethosbmp.hobby4life.nl/
Firmware
Firmware updates for the X20 Internal TD-ISRM RF module, external modules and other
devices like receivers etc. are stored here. They can then be flashed from here via the
external S.Port on the radio, or OTA (Over The Air). The new firmware must be copied to
the Firmware folder after placing the X20 in boot-loader mode and connecting to a PC via
USB.
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Tap on the Firmware folder to view the firmware files that have been copied to this
folder. Then tap on the Flash option in the popup dialog. The example above shows the
TD-ISRM RF module being updated.
The example above shows an S8R receiver about to be updated via the S.Port connection
on the radio.
The example above shows a TD-R18 receiver about to be updated Over-The-Air via the
wireless link to the bound receiver.
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The example above shows the X20 bootloader being updated.
The files may also be copied, moved or deleted.
Logs
Data logs are stored here.
USB drive path: SD Card (drive letter)/Logs/
models/
The radio stores model files here. These files cannot be edited by the user, but may be
backed up or shared from here.
USB drive path: SD Card (drive letter)/models/
Starting with v1.1.0 Alpha 17 there are Sub Folders for each user created model category
folder.
screenshots/
Screenshots created by the Screenshot Special Function are stored here. Refer to the
Model / Special Functions section.
USB drive path: SD Card (drive letter)/screenshots/
scripts/
This folder is used to store Lua scripts. Scripts may be organized into individual folders.
radio.bin
This file is created by the X20 system when first used and stores system settings. It
should be backed up together with the models folder above before updating the
firmware, to allow downgrading to the earlier version if required.
The firmware update file firmware.bin should be saved here in the root folder of the SD
card when doing a radio firmware update. After saving the new firmware.bin file, the
update will automatically be flashed into the radio when it is disconnected from the PC.
(Please note that you also may need to update the SD card and radio flash drive contents
at the same time.)
USB drive path: SD Card (drive letter)/radio.bin
USB drive path: SD Card (drive letter)/firmware.bin
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X20/X20S and Ethos v1.2.10 User Manual
Alerts
The System Alerts are:
Silent Mode Check
A Silent Mode Alert will be given at startup when Silent Mode Check is ON and the Audio
Mode has been set to Silent in System / General
Main Battery Check
A speech 'Radio Battery is Low' Alert will be given when Main Battery Check is ON and the
main radio battery is below the threshold set in the 'Low voltage' parameter in System /
Battery.
RTC Battery Check
A speech 'RTC Battery is Low' Alert will be given when RTC Battery Check is ON and the RTC
coin battery is below 2.5 , the default RTC battery threshold. It may be turned off until the
RTC battery has been replaced, but should not be left off indefinitely. The real time is used
in data logging, and an invalid time will cause difficulty in reading the logs, especially in
distinguishing flight sessions.
Inactivity
A speech 'No Activity for a Long Time' Alert will be given when the radio has not been used
for longer than the 'Inactivity' time, and also a haptic alert in case the radio volume is
turned right down. The default is 10 minutes.
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X20/X20S and Ethos v1.2.10 User Manual
Date and Time
The Date and Time settings are:
24 Hour time
The clock displays in 24 hour format when enabled.
Display seconds
The clock will display seconds when enabled.
Date
Should be set to the current date. This is used in the logs.
Time
Should be set to the current time. This is used in the logs.
Time Zone
Allows configuration of the user's time zone.
djust RTC Speed
The Real Time Clock may be calibrated to compensate for any drift in the clock, up to 41
seconds per day.
For the calibration, find out how many seconds your clock gains or loses in 24 hours.
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