YGV639 Datasheet, PDF (2/34 Pages) YAMAHA CORPORATION – Video Controller 1 with Enhanced Functions

● How VC1E creates an image plane
YGV639
Image Plane Constitution
The screen which VC1E displays consists of 341 hierarchical images, called a layer, one backdrop plane,
and a border plane with a single color.
Any one among sprite, two or more lines, and text can be selected in one layer. One sprite, one character
string, and lines (up to 510) can be displayed on one layer.
(1) Sprite
(2) Two or more lines
(3) character string
abc
The display priority order of layers is in order of a layer, a backdrop plane, and a border plane from the top.
When a layer or an external video image is not displayed, the border color which is set for the border plane is
displayed.
Also when sprites are overlaid and displayed, a lower image comes to appear by setting the surroundings
of sprites as a transparent color. Moreover, images can also be overlaid as translucent. This is called alpha
blending.
2