DMA
Time Slot
Allocation
l
Horizontal
Line (Cont'd)
Some sprites are unusable if the display starts early due to an
extra
word(s) associated with a wide display andlor horizontal
scrolling. In
this
case, the bit-plane DMA steals the cycles nor-
mally allocated to the sprites, as illustrated above.
Hardware stop installed here. Data fetch cannot begin any
sooner than cycle
18.
This allows the user to wipe out most of
the sprites if desired (by defining an extra-wide display) but
leaves the audio and disk DMA untouched.
I
m
L
I
Sprite DMAt
tThese operations only take slots if the
(2
words/channel)
associated operation
is
being performed
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