Commodore Amiga A1000, Hardware Reference Manual

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Bit-Plane Assignment in Dual-playfield Mode .............62
COLOR REGISTERS IN DUAL-PLAYFIELD MODE ...............65
DUAL-PLAYFIELD PRIORITY AND CONTROL ..................66
ACTIVATING DUAL-PLAYFIELD MODE .......................67
DUAL PLAYFIELD SUMMARY ...............................67
Bit-planes and Display Windows of All Sizes .............68
WHEN THE BIG PICTURE IS LRGR THAN THE DISPLAY WINDOW .68
MAXIMUM DISPLAY WINDOW SIZE...........................74
Moving (Scrolling) Playfields ...........................75
VERTICAL SCROLLING....................................75
HORIZONTAL SCROLLING .................................77
SCROLLED PLAYFIELD SUMMARY ...........................80
Advanced Topics..........................................81
INTERACTIONS AMONG PLAYFIELDS AND OTHER OBJECTS ......81
HOLD-AND-MODIFY MODE .................................81
FORMING A DISPLAY WITH SEVERAL DIFFERENT PLAYFELD ....84
USING AN EXTERNAL VIDEO SOURCE .......................84
SUMMARY OF PLAYFIELD REGISTERS .......................84
Summary of Color Selection ..............................87
COLOR REGISTER CONTENTS ..............................87
SOME SAMPLE COLOR REGISTER CONTENTS ..................88
COLOR SELECTION IN LOW-RESOLUTION MODE ...............88
COLOR SELECTION IN HOLD-AND-MODIFY MODE ..............90
COLOR SELECTION IN HIGH-RESOLUTION MODE ..............90
Chapter 4 SPRITE HARDWARE .................................93
Introduction.............................................93
ABOUT THIS CHAPTER....................................94
Forming a Sprite ........................................94
SCREEN POSITION ......................................94
SIZE OF SPRITES ......................................97
SHAPE OF SPRITES .....................................97
SPRITE COLOR..........................................98
DESIGNING A SPRITE...................................101
BUILDING THE DATA STRUCTURE..........................101
Displaying a Sprite.....................................106
SELECTING A DMA CHANNEL AND SETTING THE POINTERS.....107
RESETTING THE ADDRESS POINTERS ......................107
SPRITE DISPLAY EXAMPLE...............................108
Moving a Sprite.........................................110
Creating Additional Sprites.............................111
SPRITE PRIORITY......................................112
Reusing Sprite DMA Channels ............................113
Overlapped Sprites......................................115
Attached Sprites .......................................117
Manual Mode ............................................120
Sprite Hardware Details ................................121
Summary of Sprite Registers.............................124
POINTERS.............................................124
CONTROL REGISTERS....................................124
DATA REGISTERS ......................................126
Summary of Sprite Color Registers.......................126
INTERACTIONS AMONG SPRITES AND OTHER OBJECTS ........128
Chapter 5 AUDIO HARDWARE..................................129
Introduction............................................129
INTRODUCING SOUND GENERATION.........................130
THE AMIGA SOUND HARDWARE.............................133
Forming and Playing a Sound ............................134