# getValue(source)

Returns the value of a source.

The list of fixed sources:

| OpenTX Version | Radio                                                                                                                                                                                                                                                                                                                        |
| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 2.0            | [all](http://downloads-20.open-tx.org/firmware/lua_fields.txt)                                                                                                                                                                                                                                                               |
| 2.1            | [X9D and X9D+](http://downloads-21.open-tx.org/firmware/lua_fields_taranis.txt), [X9E](http://downloads-21.open-tx.org/firmware/lua_fields_taranis_x9e.txt)                                                                                                                                                                  |
| 2.2            | [X9D and X9D+](http://downloads.open-tx.org/2.2/release/firmware/lua_fields_x9d.txt), [X9E](http://downloads.open-tx.org/2.2/release/firmware/lua_fields_x9e.txt), [Horus](http://downloads.open-tx.org/2.2/release/firmware/lua_fields_x12s.txt)                                                                            |
| 2.3            | [X9D and X9D+](http://downloads.open-tx.org/2.3/release/firmware/lua_fields_x9d.txt), [X9E](http://downloads.open-tx.org/2.3/release/firmware/lua_fields_x9e.txt), [X7](http://downloads.open-tx.org/2.3/release/firmware/lua_fields_x7.txt), [Horus](http://downloads.open-tx.org/2.3/release/firmware/lua_fields_x12s.txt) |

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
  * far all non allowed sensors while FAI MODE is active
* `table` GPS position is returned in a table:
  * `lat` (number) latitude, positive is North
  * `lon` (number) longitude, positive is East
  * `pilot-lat` (number) pilot latitude, positive is North
  * `pilot-lon` (number) pilot longitude, positive is East
* `table` GPS date/time, see getDateTime()
* `table` Cells are returned in a table (except where no cells were detected in which case the returned value is 0):
  * table has one item for each detected cell:
  * key (number) cell number (1 to number of cells)
  * value (number) current cell voltage

### 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.