HARDWARE Manual

VDP2 User's Manual

Rel.2


Introduction

This manual explains the functions and usage of VDP2 (video display processor 2). VDP2 controls the scroll screen and the display priority.

Manual structure

This manual consists of the following chapters, a table of contents , and an index .

Chapter 1 Functions of VDP2

■ 1.1 System configuration
■ 1.2 Address map
● VRAM
● Color RAM
● Register
■ 1.3 Scroll function
● Display screen
● Scroll screen
● Line screen
● Window
■ 1.4 Priority function
● Priority function
● Color calculation function
● Color offset function
● Shadow function

Chapter 2 TV screen

■ 2.1 TV screen mode
● Dedicated high resolution graphic mode
■ 2.2 Interlaced mode
■ 2.3 TV screen configuration
■ 2.4 TV screen mode register
■ 2.5 External signal and scanning status
● External signal enable register
● Screen status register
● H counter register
● V counter register

Chapter 3 RAM

■ 3.1 Address map
● VRAM size register
■ 3.2 VRAM bank split
● RAM control register
■ 3.3 VRAM access method during the display period
● VRAM access during the display period
● Access to image data
● Access to vertical cell scroll table data
● Read / write access by CPU
● VRAM cycle pattern register specification procedure
● VRAM cycle pattern register
■ 3.4 Color RAM mode
● RAM control register

Chapter 4 Scroll screen

■ 4.1 Screen display control
● Screen display enable register
■ 4.2 Scroll screen configuration
● Cell format
● Bitmap format
■ 4.3 cell
● Number of character colors
● Cell data structure
● Transparent dots
● RGB format dot data
■ 4.4 Character pattern
● Character size and cell layout
■ 4.5 Character control register
■ 4.6 Pattern name table (page)
● Data structure of pattern name table
● Pattern name data
● Pattern name control register
■ 4.7 plane
● Plain size
● Plain size register
■ 4.8 Map
● Map specification register
● Map size
● Map offset register
● Normal scroll screen map register
● Rotation scroll screen map register
■ 4.9 Bitmap
● Bitmap size
● Bitmap color count
● Bitmap pattern
● Bitmap palette number
● Special function bit
● Bitmap palette number register
■ 4.10 Display area
● Display area
● Screen over processing
● Screen over pattern name
● Screen over pattern name register
■ 4.11 Mosaic processing
● Mosaic control register

Chapter 5 Normal scroll screen

■ 5.1 Screen scroll function
● Screen scroll value register
■ 5.2 Enlargement / reduction function
● Coordinate increment register
● Reduction enable register
■ 5.3 Line & vertical cell scroll function
● Line scroll function
● Vertical cell scroll function
● Line & vertical cell scroll control register
● Line scroll table address register
● Vertical cell scroll table address register

Chapter 6 Rotating scroll screen

■ 6.1 Rotation scroll coordinate calculation
■ 6.2 Rotation scroll screen display control
● RAM control register
■ 6.3 Rotation parameter control
● Data structure of rotation parameter table
● Rotation parameter table
● Rotation parameter read control register
● Rotation parameter table address register
● Rotational read of frame buffer
● Switching rotation parameters
● Rotation parameter mode register
■ 6.4 Coefficient table control
● RAM control register
● Coefficient table control register
● Coefficient table address offset register

Chapter 7 Line screen

■ 7.1 Line color screen
● Line color screen table address register
■ 7.2 Back screen
● Back screen table address register

Chapter 8 Window

■ 8.1 Window area
● Normal rectangular window
● Window position register
● Normal line window
● Line window table address register
● Sprite window
● Sprite control register
● Window effective area for the screen
■ 8.2 Window processing
● Window control register

Chapter 9 Sprite Data

■ 9.1 Sprite data
● Sprite type
● Sprite color mode
■ 9.2 Priority and color calculation
● Priority number selection
● Color operation enable condition
● Color calculation ratio selection
● Sprite control register
● Priority number register
● Color calculation ratio register

Chapter 10 Dot Color Data

■ 10.1 Palette format dot color data
● Sprite dot color data
● Scroll dot color data
● Color RAM address offset register
■ 10.2 RGB format dot color data
● Sprite dot color data
● Scroll dot color data
■ 10.3 Special function code
● Special function code select register
● Special function code register

Chapter 11 Priority Function

■ 11.1 Priority function
● Priority number
● Priority number register
■ 11.2 Special priority function
■ 11.3 Insert line color screen
● Line color screen enable register

Chapter 12 Color Calculation

■ 12.1 Color calculation function
● Normal color calculation
● Extended color calculation function
● Blur calculation function
● Color operation control register
● Color calculation ratio register
■ 12.2 Special color calculation function
● Special color calculation mode register

Chapter 13 Color Offset Function

■ 13.1 Color offset specification
● Color offset enable register
● Color offset select register
● Color offset register

Chapter 14 Shadow Function

■ 14.1 Shadow processing
● Normal shadow
● MSB shadow
● Shadow control register

Chapter 15 How to use VDP2

■ 15.1 Operation flow
■ 15.2 How to use RAM
● VRAM
● Definition of color RAM
● Reference to color RAM
● Register
■ 15.3 Bit configuration diagram
■ 15.4 Usage techniques
Techniques for making bitmaps arbitrary size
Technique to double buffer VRAM

Chapter 16 Quick Reference

Manual notation

Chart table of contents

index


HARDWARE Manual
Copyright SEGA ENTERPRISES, LTD., 1997