Commodore Amiga - Data Registers

Bit positions:
oBits 15-8 specify vertical stop position for a sprite image, bits V7 - YO.
o Bit 7 is the attach bit. This bit is valid only for odd-numbered sprites. It indi-
cates
that sprites 0, 1 (or 2,3 or 4,5 or 6,7) will, for color interpretation, be con-
sidered as paired, and as such will be called four bits deep. The odd-numbered
(higher number) sprite contains bits with the higher binary significance.
During attach mode, the attached sprites are normally moved horizontally and
vertically together under processor control. This allows a greater selection of
colors within the boundaries of the sprite itself. The sprites, although attached,
remain capable of independent motion, however, and they will assume this
larger color
set only when their edges overlay one another.
oBits 6-3 are reserved for future use (make zero).
oBit 2 is bit V8 of vertical start.
oBit 1 is bit V8 of vertical stop.
oBit 0 is bit HO of horizontal start.
Position and control registers for the other sprites are:
DATA REGISTERS
SPR1POS
SPR2POS
SPR3POS
SPR4POS
SPR5POS
SPR6POS
SPR7POS
SPR1CTL
SPR2CTL
SPR3CTL
SPR4CTL
SPR5CTL
SPR6CTL
SPR7CTL
The following registers, although defined
in the address space of the main processor, are
normally used only by the display processor. They are the holding registers for the
data
obtained by DMA cycles. .
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