Help manual osc

[atmelcool]

Hi! The manual is written:
Invert
Adds an upside-down copy of the waveform. Invert plus phase modulation sounds similar
to classic PWM, as only the phase of the original wave is shifted around, while the
phase of the inverted copy remains fixed.

I used Google translator, but did not understand what it does? Explain to me please in detail which makes this option? I understand very little English and translation software translation is not correct. Thank U!

[bmrzycki]

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