Returns gray value which can be used in LCD functions

@status current Introduced in 2.0.13

Parameters

none

Return value

• (number) a value that represents amount of greyness (from 0 to 15)

Notice

Only available on Taranis

Return current RTC system date as unix timstamp (in seconds since 1. Jan 1970)

Please note the RTC timestamp is kept internally as a 32bit integer, which will overflow in 2038.

Parameters

none

Return value

• number Number of seconds elapsed since 1. Jan 1970

This functions allows for sending telemetry data toward the TBS Crossfire link.

When called without parameters, it will only return the status of the output buffer without sending anything.

@status current Introduced in 2.2.0, retval nil added in 2.3.4

Parameters

• command command

• data table of data bytes

Return value

• boolean data queued in output buffer or not.

• nil incorrect telemetry protocol.

This function reads/writes the Multi protocol buffer to interact with a protocol².

@status current Introduced in 2.3.2

Parameters

• address to read/write in the buffer

  @param (optional): value to write in the buffer

Return value

• buffer value (number)

Get available memory remaining in the Heap for Lua.

Parameters

none

Return value

• usage (number) a value returned in b

Change the working directory

@status current Introduced in 2.3.0

Parameters

• directory (string) New working directory

Return value

none

Get percent of already used Lua instructions in current script execution cycle.

@status current Introduced in 2.2.1

Parameters

none

Return value

• usage (number) a value from 0 to 100 (percent)

Stops key state machine. See Key Events for the detailed description.

@status current Introduced in 2.0.0

Parameters

• key (number) key to be killed, can also include event type (only the key part is used)

Return value

none

Get channel assigned to stick. See Default Channel Order in General Settings

@status current Introduced in 2.0.0

Parameters

• stick (number) stick number (from 0 to 3)

Play a file from the SD card

@status current Introduced in 2.0.0, changed in 2.1.0

Parameters

• path (string) full path to wav file (i.e. “/SOUNDS/en/system/tada.wav”)

Pops a received SPORT packet from the queue. Please note that only packets using a data ID within 0x5000 to 0x50FF (frame ID == 0x10), as well as packets with a frame ID equal 0x32 (regardless of the data ID) will be passed to the LUA telemetry receive queue.

@status current Introduced in 2.2.0

Parameters

none

Play a time value (text to speech)

@status current Introduced in 2.1.0

Parameters

• duration (number) number of seconds to play. Only integral part is used.

Return the RAS value or nil if no valid hardware found

@status current Introduced in 2.2.0

Parameters

none

Pops a received Crossfire Telemetry packet from the queue.

@status current Introduced in 2.2.0

Parameters

none

Resets the radio global timer to 0.

@status current Introduced in 2.2.2, param added in 2.3

Parameters

• (optional) : if set to 'all', throttle ,throttle percent and session timers are reset too

Set baudrate for serial port(s) affected to LUA

@status current Introduced in 2.3.12

Parameters

baudrate Desired baudrate

@param num (optional): maximum number of bytes to read. If non-zero, serialRead will read up to num characters from the buffer. If 0 or left out, serialRead will read up to and including the first newline character or the end of the buffer. Note that the returned string may not end in a newline if this character is not present in the buffer.

Reads characters from the serial port. The string is allowed to contain any character, including 0.

@status current Introduced in 2.3.8

Parameters

none

Return rotary encoder current speed

@status current Introduced in 2.3.10

Parameters

none

Return flight mode data.

@status current Introduced in 2.1.7

Parameters

• mode (number) flight mode number to return (0 - 8). If mode parameter

  is not specified (or contains invalid value), then the current flight mode data is returned.

Return value

• multiple returns 2 values:

  • (number) (current) flight mode number (0 - 8)

  • (string) (current) flight mode name

Generate haptic feedback

@status current Introduced in 2.2.0

Parameters

• duration (number) length of the haptic feedback in milliseconds

• pause (number) length of the silence after haptic feedback in milliseconds

• flags (number):

  • 0 or not present play with normal priority

  • PLAY_NOW play immediately

Return value

none

This functions allows for sending SPORT / ACCESS telemetry data toward the receiver, and more generally, to anything connected SPORT bus on the receiver or transmitter.

When called without parameters, it will only return the status of the output buffer without sending anything.

@status current Introduced in 2.3

Parameters

• module module index (0 = internal, 1 = external)

• rxUid receiver index

• sensorId physical sensor ID

• frameId frame ID

• dataId data ID

• value value

Return value

• boolean data queued in output buffer or not.

Get stick that is assigned to a channel. See Default Channel Order in General Settings.

@status current Introduced in 2.0.0

Parameters

• channel (number) channel number (0 means CH1)

Return value

• number Stick assigned to this channel (from 0 to 3)

@param str (string) String to be written to the serial port.

Writes a string to the serial port. The string is allowed to contain any character, including 0.

@status current Introduced in 2.3.10

Parameters

none

Return value

none

This functions allows for sending SPORT telemetry data toward the receiver, and more generally, to anything connected SPORT bus on the receiver or transmitter.

When called without parameters, it will only return the status of the output buffer without sending anything.

@status current Introduced in 2.2.0, retval nil added in 2.3.4

Parameters

• sensorId physical sensor ID

• frameId frame ID

• dataId data ID

• value value

Return value

• boolean data queued in output buffer or not.

• nil incorrect telemetry protocol.

Get RSSI value as well as low and critical RSSI alarm levels (in dB)

@status current Introduced in 2.2.0

Parameters

none

Return value

• rssi RSSI value (0 if no link)

• alarm_low Configured low RSSI alarm level

• alarm_crit Configured critical RSSI alarm level

Raises a pop-up on screen that asks for confirmation

@status current Introduced in 2.2.0, changed from (title, event) to (title, message, event) in 2.3.8

Parameters

• title (string) title to display

• message (string) text to display

• event (number) the event variable that is passed in from the Run function (key pressed)

Return value

• "CANCEL" user pushed EXIT key

Notice

Use only from stand-alone and telemetry scripts.

Load a Lua script file. This is similar to Lua's own loadfile() API method, but it uses OpenTx's optional pre-compilation feature to save memory and time during load.

Return values are same as from Lua API loadfile() method: If the script was loaded w/out errors then the loaded script (or "chunk") is returned as a function. Otherwise, returns nil plus the error message.

@status current Introduced in 2.2.0

Example

Parameters

• file (string) Full path and file name of script. The file extension is optional and ignored (see mode param to control which extension will be used). However, if an extension is specified, it should be ".lua" (or ".luac"), otherwise it is treated as part of the file name and the .lua/.luac will be appended to that.

• mode (string) (optional) Controls whether to force loading the text (.lua) or pre-compiled binary (.luac) version of the script. By default OTx will load the newest version and compile a new binary if necessary (overwriting any existing .luac version of the same script, and stripping some debug info like line numbers). You can use mode to control the loading behavior more specifically. Possible values are:

Return value

• function The loaded script, or nil if there was an error (e.g. file not found or syntax error).

• string Error message(s), if any. Blank if no error occurred.

Notice

Note that you will get an error if you specify mode as "b" or "t" and that specific version of the file does not exist (eg. no .luac file when "b" is used). Also note that mode is NOT passed on to Lua's loader function, so unlike with loadfile() the actual file content is not checked (as if no mode or "bt" were passed to loadfile()).

Return the internal GPS position or nil if no valid hardware found

@status current Introduced in 2.2.2

Parameters

none

Return value

• table representing the current radio position

  • lat (number) internal GPS latitude, positive is North

  • lon (number) internal GPS longitude, positive is East

Returns (some of) the general radio settings

@status current Introduced in 2.0.6, imperial added in TODO, language and voice added in 2.2.0, gtimer added in 2.2.2.

Parameters

none

Return value

• table with elements:

  • battWarn (number) radio battery range - warning value

  • battMin (number) radio battery range - minimum value

Returns radio timers

@status current Introduced added in 2.3.0.

Parameters

none

Return value

• table with elements:

• gtimer (number) radio global timer in seconds

• session (number) radio session in seconds

Return detailed information about field (source)

The list of valid sources is available:

Return OpenTX version

@status current Introduced in 2.0.0, expanded in 2.1.7, radio type strings changed in 2.2.0, os name added in EdgeTX 2.4.0

Example

This example also runs in OpenTX versions where the function returned only one value:

Output of the above script in simulator:

Play a tone

@status current Introduced in 2.1.0

Parameters

• frequency (number) tone frequency in Hz (from 150 to 15000)

Raises a pop-up on screen that shows a warning

@status current Introduced in 2.2.0

Parameters

• title (string) text to display

Return current system date and time that is kept by the RTC unit

Parameters

none

Raises a pop-up on screen that allows uses input

@status current Introduced in 2.0.0

Parameters

• title (string) text to display

@status current Introduced in 2.2.0

Parameters

• id Id of the sensor, valid range is from 0 to 0xFFFF

• subID subID of the sensor, usually 0, valid range is from 0 to 7

• instance instance of the sensor (SensorID), valid range is from 0 to 0xFF

• value fed to the sensor

• unit unit of the sensor

• precision the precision of the sensor

  • 0 or not present no decimal precision.

  • != 0 value is divided by 10^precision, e.g. value=1000, prec=2 => 10.00.

• name (string) Name of the sensor if it does not yet exist (4 chars).

  • not present Name defaults to the Id.

  • present Sensor takes name of the argument. Argument must have name surrounded by quotes: e.g., "Name"

Return value

• true, if the sensor was just added. In this case the value is ignored (subsequent call will set the value)

Notice

All three parameters id, subID and instance can't be zero at the same time. At least one of them must be different from zero.

Play a numerical value (text to speech)

@status current Introduced in 2.0.0

Parameters

• value (number) number to play. Value is interpreted as integer.

• unit (number) unit identifier [Full list]((../appendix/units.html))

• attributes (unsigned number) possible values:

  • 0 or not present plays integral part of the number (for a number 123 it plays 123)

  • PREC1 plays a number with one decimal place (for a number 123 it plays 12.3)

Return value

none

Returns the value of a source.

The list of fixed sources:

In OpenTX 2.1.x the telemetry sources no longer have a predefined name. To get a telemetry value simply use it's sensor name. For example:

• Altitude sensor has a name "Alt"

• to get the current altitude use the source "Alt"

• to get the minimum altitude use the source "Alt-", to get the maximum use "Alt+"

@status current Introduced in 2.0.0, changed in 2.1.0, Cels+ and Cels- added in 2.1.9

Parameters

• source can be an identifier (number) (which was obtained by the getFieldInfo())

  or a name (string) of the source.

Return value

• value current source value (number). Zero is returned for:

  • non-existing sources

  • for all telemetry source when the telemetry stream is not received

Notice

Getting a value by its numerical identifier is faster then by its name. While Cels sensor returns current values of all cells in a table, a Cels+ or Cels- will return a single value - the maximum or minimum Cels value.

Return the time since the radio was started in multiple of 10ms

The timer internally uses a 32-bit counter which is enough for 497 days so overflows will not happen.

@status current Introduced in 2.0.0

Parameters

none