Definitions - Yamaha V9938 Programmer's Manual

DEFINITIONS

A
Attribute
The property of an object, which controls how object looks like on the screen. Attribute
can be a color, position of an object, or control which pixel should have specific color
B
Background
object property
Is an or which is perceived to be in the background to another property or
object. For example, for a character displayed on the screen the pixels of its image is said
to have foreground color, while other pixels to have background color. In case of sprites,
they may be said to appear in the foreground to the font patterns, as sprites overlap
Foreground
images of the font. See also
C
Collision
Sprites are said to collide when their dots having color code 1 (simply saying – dots
identified with binary 1s in their sprite pattern generator table) overlap. In some
circumstances such behavior may be changed in favor or mixing sprite colors to have
pseudo-multi-colored sprites
Color
A property of the pixel on the screen. Color of the pixel may come from various sources:
from global color register, from pattern color table or from sprite color table. Colors can
also be coded in the palette registers through setup of red, green and blue components –
in this case, if color table of the patterns and sprites remain unchanged, actual colors,
associated with them, may be different
Command
A special sequence of VDP operations, a kind of hardware acceleration. Command is
expected to streamline CPU-VDP-VRAM operations, unload CPU and increase data transfer
speed.
E
Expansion RAM
This random access memory is used to store non-displayed data or register information,
and is not necessary for proper operation of the VDP. Maximal size or expansion RAM is
64K bytes. Due to specific purposes of this RAM, it is rarely used in applications.
© 1985 ASCII CORP. / NIPPON GAKKI CO. © 2010-2015 Eugeny Brychkov
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