IBM RT Series Hardware Reference Manual page 371

TNL SN20-9844 (March 1987) to 75X0235
Set Video Off (X'3F')
The set video ofT graphic operation disables the video data line to the display monitor. When
the video data line is disabled, the information contained in the displayable bit map area is not
displayed on the monitor. The monitor instead produces the background screen type, either an
all white screen or an all black screen, depending on the current setting of the black on white
background bit in the control/status register.
Example: Set Video OfT
Queue Queue Action By
Address Data Queue Processing
Que Ptr X'D3FO' Execute set video ofT - Disable the video data line.
Extended Monochrome Graphics Adapter
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