■ DESCRIPTION

The MB90050 is an on-screen display controller for displaying text and graphics on the TV screen.

The MB90050 controls a display area of 35 characters by 16 lines, and provides each character composed of 24 × 32 dots at most. The display functions include a wealth of characters with qualifying functions such as character background shading (shadow casting) , sprite character functions and graphic character functions, contributing to the use of control GUI displays. The MB90050 incorporates display memory (VRAM) , character font ROM, and sync signal generation circuit and video signal generation circuit supporting the NTSC and PAL systems, allowing text and graphics to be displayed in

conjunction with a small number of external components.

■ FEATURES

• Main screen display capacity

35 characters × 16 lines (maximum 560 characters)

• Character configuration

Normal characters : 24 × 32 dots

Graphic characters : 12 × 16 dots* (colorable per 1 dot)

• Font display configuration

Three horizontal width settings (selectable setting L/M/S for each character) per character.

L size : 24 dots

M size : 18 dots

S size : 12 dots

Two vertical height settings (selectable A/B for each line) per line.

A : 18 to 32 dots (setting per 2 dots)

B : 18 to 32 dots (setting per 2 dots)

(These sizes are dot sizes of typical character. Each size of graphic characters uses half the number of dots of typical characters. Note, however, that both of the typical and graphic characters are the same in character area size.)

• Character types

Usable all 512 character types (font ROM+, font RAM)

Font ROM : 512 character types (all area user setting)

Font RAM : 8 character types (all area user command setting)

Capable of setting a specific eight-character area in font ROM so that the area is replaced with font RAM.

• Display modes

Character : Normal character/graphic character (set for each character)

Character trimming : Side trimming 1/side trimming 2/patern background 1/patern background 2 (set for each screen)

Character background : None/Solid-fill/Shaded background (concave) /Shaded background (convex) (set for each character)

Line background : None/Solid-fill/Shaded background (concave) /Shaded background (convex) (set for each line)

Character enlargement : Normal, Double width, Double height, Double width × double height (set for each line)

Brink : OFF/ON (set for each character)

• Main screen display position control

Horizontal display position : Control in 2-dot units (movable through the entire screen)

Vertical display position : Control in 2-dot units (movable through the entire screen)

Line spacing control : 0 to 14 dots, 2-dot units (set for each line)

Sprite character display control

Capable of displaying one block for an arbitrary character on the topmost layer on the screen.

Sprite character display : OFF/ON (graphic character display)

Sprite character types : 256 types (character codes 000H to 0FFH)

Sprite character configuration : 1 character/2 characters horizontal/2 characters vertical/2×2 characters

Sprite character horizontal display position : Control in 1-dot units

Sprite character vertical display position : Control in 1-dot units

Screen background color display control

Capable of displaying an arbitrary color on the entire bottommost layer on the screen.

Screen background color display : OFF/ON

• Display colors

Digital output : 16 colors selectable from among 64 colors (built in palette circuit)

Video output : Any 16 colors selectable (Command setting enable)