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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 -- or at least I thought it did, recent testing shows that <umvk> is also needed to stop the VOX from triggering.  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> <umvk> <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> <mvk +DigitalVOX> <umb +right shift> <cpx> * "village." ;

    Note that originally I thought the
+DigitalVOX signal would not be generated once <sac> was in effect in items 526 though 533 even if there was enough sound energy to trigger the VOX however in recent (08/25/20) testing I definitely saw the voice key trigger after a <sac> so we're religiously unmapping and remapping it's signal, whether this is because something got changed in the code since <sac> was introduced or not remains to be seen, I guess it's possible I only noticed it because I was using typing items where any single positive response ended the typing when I wasn't expecting it to end whereas when people are gathering data in multiple trials the odd data point preempted by a VOX signal may not be so noticible.  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).

    Another example involves switching from playing audio files, gathering ratings and then recording vocalizations:

<ep>
<fd 30> <zil> <zor> <zol>
<id RecordVocal 0, 1500> <id DigitalVOX> <id keyboard>
<vzk +backspace> <vzk +shift> <vzk +right shift> <vzk +DigitalVOX>
<inst hardmargin> <safemode 1> <clfb> <cr> <eop>
0 <inst .1, .1, .92>
"Elicited Imitation Test ", <inst nl>,<inst nl>,
"1. ", "Listen ", "to ", "each ", "statement ", "and ", "decide ", "if ", "it ", "is ", "true ", "or ", "false, ", "or ", "if ", "you ", "are ", "not ", "sure ", "about ", "it. ", "You ", "can ", "indicate ", "your ", "opinion ", "by ", "pressing ", "left ", "shift ", "key ", "if ", "it ", "is ", "True, ", "right ", "shift ", "key ", "if ", "it ", "is ", "False, ", "and ", "backspace ", "key ", "if ", "you ", "are ", "Unsure. ", "You ", "have ", "just ", "5 ", "seconds ", "for ", "making ", "your ", "choice. ", "Immediately ", "after ", "indicating ", "your ", "opinion, ", "you ", "will ", "hear ", "a ", "beep ", "sound. ", <inst nl>, <inst nl>, "Hit the spacebar to continue...";
0 <inst .1, .1, .92> "2. ", "Immediately ", "after ", "the ", "beep ", "sound, ", "(1) ", "if ", "the ", "statement ", "is ", "grammatical, ", "repeat ", "it ", "as ", "it ", "is ", "and ", "(2) ", "if ", "the ", "statement ", "is ", "ungrammatical, ", "repeat ", "it ", "in ", "correct ", "English. ", <inst nl>, <inst nl>,
"3. ", "After ", "that, ", "press ", "the ", "Space ", "key ", "to ", "go ", "to ", "the ", "next ", "statement. ", "You ", "have ", "just ", "15 ", "seconds ", "to ", "repeat ", "the ", "statement." <inst nl>, <inst nl>, "Hit the spacebar to continue...";
0 <inst .1, .1, .92> "Let's ", "first ", "do ", "a ", "practice ", "test ", "with ", "three ", "statements ", "to ", "make ", "sure ", "that ", "you ", "are ", "familiar ", "with ", "the ", "procedure ", "of ", "the ", "test. ",<inst nl>, <inst nl>, "Hit the spacebar to start the practice...";

+510 / <timeout 5000> <sac> <umvk> <umpr> <umnr> <mpr +shift> <mnr +right shift> <mnr +backspace> <wav 2> "Practice Items\1.wav" / "True/false/uncertain?" * <continue>;
+511 <timeout 15000> <sac 0> <mvk +DigitalVOX> <umpr> <umnr> <wav 2> "beep" / * ;
0 "Hit the spacebar to continue...";

+520 / <timeout 5000> <sac> <umvk> <umpr> <umnr> <mpr +shift> <mnr +right shift> <mnr +backspace> <wav 2> "Practice Items\2.wav" / "True/false/uncertain?" * <continue>;
+521 <timeout 15000> <sac 0> <mvk +DigitalVOX> <umpr> <umnr> <wav 2> "beep" / * ;
0 "Hit the spacebar to continue...";

+530 / <timeout 5000> <sac> <umvk> <umpr> <umnr> <mpr +shift> <mnr +right shift> <mnr +backspace> <wav 2> "Practice Items\3.wav" / "True/false/uncertain?" * <continue>;
+531 <timeout 15000> <sac 0> <mvk +DigitalVOX> <umpr> <umnr> <wav 2> "beep" / * ;
0 "Hit the spacebar to continue...";

0 <inst .1, .1, .92> "That's ", "the ", "end ", "of ", "the ", "practice, ", "hit ", "the ", "spacebar ", "to ", "start ", "the ", "test...";

+1010 / <timeout 5000> <sac> <umvk> <umpr> <umnr> <mpr +shift> <mnr +right shift> <mnr +backspace> <wav 2> "EX1Version1\1.wav" / "True/false/uncertain?" * <continue>;
+1011 <timeout 15000> <sac 0> <mvk +DigitalVOX> <umpr> <umnr> <wav 2> "beep" / * ;
0 "Hit the spacebar to continue...";

! items 1020 through 1511 removed;

+1520 / <timeout 5000> <sac> <umvk> <umpr> <umnr> <mpr +shift> <mnr +right shift> <mnr +backspace> <wav 2> "EX1Version1\52.wav" / "True/false/uncertain?" * <continue>;
+1521 <timeout 15000> <sac 0> <mvk +DigitalVOX> <umpr> <umnr> <wav 2> "beep" / * ;

0 "That is the end.";



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