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operating systems generally do not support VBIs as access to hardware interrupts for unprivileged user programs could compromise the system stability. Instead, various
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consoles that relied upon a central microprocessor to generate text or graphic displays. More advanced home computers featuring hardware
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is being returned to the start of the display. With VBI, the vertical blank pulse is also used to generate an
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while it is not being read to avoid screen tearing effects. This was particularly useful in simple
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provide efficient and safe ways to present graphics free of tear and flicker.
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As the VBI will be generated at the start of every displayed frame (50 Hz for
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and vertical sync pulses when the display picture has completed and the
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Computer interrupt in home computers triggered by video output.
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209:For computers that support VBIs see the page about
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172:instead in order to allow them to be multiplexed.
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133:based video display circuits generate
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242:Mentley, David E. (1984).
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58:"Vertical blank interrupt"
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245:ABCs of Atari Computers
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99:February 2024
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