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Counter Frame Duration Keyword

<CounterFrameDuration N>
<ctrfd N>

Millisecond Default Frame Duration Keyword

<msCounterFrameDuration N>
<msctrfd N>

    % switch alternative. Unlike the traditional % switch or <FrameDuration> keyword this keyword specifies a frame duration using Counter number N's value as the number of ticks, see Set Counter.  The millisecond variants of this keyword allow the frame duration to be specified in milliseconds (will be rounded to the nearest tick unless the freesync video mode option is active).

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