Turn on or off the AV display by modifying the variable address.

Location: control area.
'X' and 'Y' are the coordinates of the upper left corner of the display area.
'W' and 'H' are the width and height of the display.
Name: AVInputView, can be reset.
DescriblePointer: fixed to 0xFFFF.
VariableAddress: pointer of variable storage area (0x0000-0x6FFF).
0-turn off the AV display, non-zero turn on the AV display.
InitialValue: The default is 0.