BIOS color attributes

BIOS Color Attribute is a 8 bit value where the low 4 bits represent the character color and the high 4 bits represent the background color. For example, to print a white character 'A' with black background, the "BIOS Color Attribute" would be set to the hexadecimal value 0x0F. The highest bit of the color attribute, which is also the highest bit of the background color can take over two functions. It can either have no influence on the background color making text blink when set, effectively limiting the available background colors to only eight, or if intensive background colors are enabled the full 16 colors become available but blinking is no longer available. This behavior can be changed, i.e., using BIOS 80x86 interrupt 0x10, function 0x1003. This 16 colour palette is often used in console programs (e.g. cmd in Windows) and sometimes for chat in games (e.g. Minecraft).

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