Commodore Amiga A2000 - Table 3-8 Playfield Memory Requirements, PAL

Table 3-8: Playfield Memory Requirements, PAL
Number of Bytes
Picture Size Modes per Bit-Plane
320 X 256 Low-resolution, 8,192
non-interlaced
320 X 512 Low-resolution, 16,384
interlaced
640 X 256 High-resolution, 16,384
non-interlaced
640 X 512 High-resolution, 32,768
interlaced
NTSC EXAMPLE OF BIT PLANE SIZE
For example, using a normal, NTSC, low-resolution, non-interlaced display with 320 pixels
across each display line and a total of 200 display lines, each line of the bit-plane requires
40 bytes (320 bits divided by 8 bits per byte = 40). Multiply the 200 lines times 40 bytes
per line to get 8,000 bytes per bit-plane as given above.
A low-resolution, non-interlaced playfield made up of two bit-planes requires 16,000 bytes
of memory area. The memory for each bit-plane must be continuous, so you need to have
two 8,000-byte blocks of available memory.
Figure 3-7 shows an 8,000-byte memory area organized as 200 lines of 40 bytes each,
providing 1 bit for each pixel position in the display plane.
- Playfield Hardware 47 -