By POKEing a number into color memory, you can change the color of the character in that position on the screen. POKEing a number from 0 to 7 gives the normal character colors. POKEing a number between 8 and 15 puts the space into multi-color mode. In other words, turning BIT 3 ON in color memory, sets MULTI-COLOR MODE. Turning BIT 3 OFF in color memory, sets the normal, HIGH-RESOLUTION mode.
Once multi-color mode is set in a space, the bits in the character determine which colors are displayed for the dots. For example, here is a picture of the letter A, and its bit pattern:
IMAGE BIT PATTERN ** 00011000 **** 00111100 ** ** 01100110 ****** 01111110 ** ** 01100110 ** ** 01100110 ** ** 01100110 00000000
In normal or high-resolution mode, the screen color is displayed everywhere there is a 0 bit, and the character color is displayed where the bit is a 1. Multi-color mode uses the bits in pairs, like so:
IMAGE BIT PATTERN AABB 00011000 CCCC 00111100 AABBAABB 01100110 AACCCCBB 01111110 AABBAABB 01100110 AABBAABB 01100110 AABBAABB 01100110 00000000
In the image area above, the spaces marked AA are drawn in the background #1 color, the spaces marked BB use the background #2 color, and the spaces marked CC use the character color. The bit pairs determine this, according to the following chart:
This page has been created by Sami Rautiainen. | |
Read the small print. | Last updated May 12, 2002. |