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Created page with 'In programation, the raster is often referred as the act to modify the setting of inks between 2 scanlines. This is a way to display more than the usual Video modes number o…'
 
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In programation, the raster is often referred as the act to modify the setting of inks between 2 scanlines.
In programation, the raster is often referred as the act to modify the setting of inks between 2 scanlines, in interrupt mode.


This is a way to display more than the usual [[Video modes]] number of colours.
This is a way to display more than the usual [[Video modes]] number of colours.
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So It has enough cycles between 2 scanlines to order this.
So It has enough cycles between 2 scanlines to order this.


You can also use Split rasterto "actually" display 2  different screens, sometoimes with different Video Modes.
You can also use Split raster to "actually" display 2  different screens, sometimes with different Video Modes. This also allows a Graphic heavy [[HUD]] with no interference with [[Scrolling]].





Revision as of 21:42, 13 October 2009

In programation, the raster is often referred as the act to modify the setting of inks between 2 scanlines, in interrupt mode.

This is a way to display more than the usual Video modes number of colours.

The time between the display of 2 Scanlines by the CRTC allow the CPU to order the Gate array to modify the setting of inks.

The screen display at 50Hz...The CPU (Z80) runs at about 4 MgHz.

So It has enough cycles between 2 scanlines to order this.

You can also use Split raster to "actually" display 2 different screens, sometimes with different Video Modes. This also allows a Graphic heavy HUD with no interference with Scrolling.