Commodore Amiga - Allocating Memory for Bit-Planes

o Hold-and-modify mode is disabled.
o Single-playfield mode is enabled.
o Composite video color is enabled.
o Genlock audio
is disabled.
o Light pen
is disabled.
o
In terlaced mode is enabled.
o External resynchronization
is disabled.
The amount of memory you need to allocate for each bit-plane depends upon the resolu-
tion modes you have selected, because high-resolution
or interlaced playfields contain
more
data and require larger bit-planes.
ALLOCATING MEMORY FOR BIT-PLANES
After you set the number of bit-planes and specify resolution modes, you are ready to
allocate memory. A bit-plane consists of an end-to-end sequence of words at consecutive
memory locations.
To allocate memory, you set the registers that point to the starting
memory address of each bit-plane you are using.
The starting address is the memory
word
that contains the bits of the upper left-hand corner of the bit-plane.
Table 3-6 shows
how much memory is needed for basic playfields. You may need to bal-
ance your color and resolution requirements against the amount of available memory you
have.
Playfield Hardware
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