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

Play a tone

@status current Introduced in 2.1.0


  • frequency (number) tone frequency in Hz

  • duration (number) length of the tone in (TODO units)

  • pause (number) length of the pause in (TODO units)

  • flags (number):

    • 0 or not present play with normal priority.
    • PLAY_BACKGROUND play in background (built in vario function used this context)
    • PLAY_NOW play immediately
  • freqIncr (number) positive number increases the tone pitch (frequency with time), negative number decreases it. Bigger number has more effect

Return value



Minimum played frequency is 150Hz even if a lower value is specified.