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Standard high-resolution graphics give you control of very small dots on the screen. Each dot in character memory can have 2 possible values, 1 for on and 0 for off. When a dot is off, the color of the screen is used in the space reserved for that dot. If the dot is on, the dot is colored with the character color you have chosen for that screen posi- tion. When you're using standard high-resolution graphics, all the dots within each 8X8 character can either have background color or foreground color. In some ways this limits the color resolution within that space. For example, problems may occur when two different colored lines cross.

Multi-color mode gives you a solution to this problem. Each dot in multi-color mode can be one of 4 colors: screen color (background color register #0), the color in background register #1, the color in back- ground color register #2, or character color. The only sacrifice is in the horizontal resolution, because each multi-color mode dot is twice as wide as a high-resolution dot. This minimal loss of resolution is more than compensated for by the extra abilities of multi-color mode.


To turn on multi-color character mode, set bit 4 of the VIC-II control register at 53270 ($D016) to a 1 by using the following POKE:

   POKE 53270,PEEK(53270)OR 16
To turn off multi-color character mode, set bit 4 of location 53270 to a 0 by the following POKE:
   POKE 53270,PEEK(53270)AND 239

Multi-color mode is set on or off for each space on the screen, so that multi-color graphics can be mixed with high-resolution (hi-res) graphics. This is controlled by bit 3 in color memory. Color memory begins at location 55296 ($D800 in HEX). If the number in color memory is less than 8 (0-7) the corresponding space on the video screen will be standard hi-res, in the color (0-7) you've chosen. If the number located in color memory is greater or equal to 8 (from 8 to 15), then that space will be displayed in multi-color mode.

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This page has been created by Sami Rautiainen.
Read the small print. Last updated December 23, 2002.