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Suppress Audio Capture Keyword

<SuppressAudioCapture [N]>
<sac [N]>

    MDSP bit 20000000 modifier, the bit that suppresses audio capture. Reset if N = 0, otherwise set. All MDSP modifiers are both parameters and switches. If N is missing the bit is set and the mode is active.

    Setting this MDSP bit stops the RecordVocal and DigitalVOX devices from being triggered by a clock on.  This is to facilitate multimodal experiments that only want to capture audio on some items and not others.  So in the example that follows the self paced reading items won't be recording any audio but once
<SuppressAudioCapture> is off in item 534 it will record vocalization and there will be a +DigitalVOX signal generated.

<ep> <d 0> <cr> <nfb> <id keyboard>
<id DigitalVox> <id RecordVocal 750> <vm desktop> <eop>

+526 <sac> <mpr +right shift> * <px .1> "More" ;
+527 <cpx> * "power" ;
+528 <cpx> * "stations" ;
+529 <cpx> * "have" ;
+530 <cpx> * "been" ;
+531 <cpx> * "built" ;
+532 <cpx> * "in" ;
+533 <cpx> * "this" ;
+534 <sac 0> <umb +right shift> <cpx> * "village." ;

    Note that the
+DigitalVOX signal will not be generated in items 526 though 533 even if there was enough sound energy to trigger the VOX.  Even though one doesn't have to worry about the VOX trigging the self paced reading items one does have to block the right shift key from providing a response the to the naming task item (534).

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