> For the complete documentation index, see [llms.txt](https://doc.open-tx.org/opentx-2-3-lua-reference-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.open-tx.org/opentx-2-3-lua-reference-guide/part_iii_-_opentx_lua_api_reference/general-functions-less-than-greater-than-luadoc-begin-general/playtone.md).

# playTone(frequency, duration, pause \[, flags \[, freqIncr]])

Play a tone

@status current Introduced in 2.1.0

## Parameters

* `frequency` (number) tone frequency in Hz (from 150 to 15000)
* `duration` (number) length of the tone in milliseconds
* `pause` (number) length of the silence after the tone in milliseconds
* `flags` (number):
* `0 or not present` play with normal priority.
* `PLAY_BACKGROUND` play in background (built in vario function uses this context)
* `PLAY_NOW` play immediately
* `freqIncr` (number) positive number increases the tone pitch (frequency with time), negative number decreases it. The frequency changes every 10 milliseconds, the change is `freqIncr * 10Hz`. The valid range is from -127 to 127.

## Return value

none