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Player/Missile graphics

Graphics XIO commands Function keys 6502 opcodes File systems
Joystick Memory map Music/sound Display list I/O errors
Player/Missile Character set File formats Display list interrupts (DLI) Vertical blank interrupts (VBI)

Player/Missile graphics RAM positioning scheme, taken from book Compute!'s First Book Of Atari Graphics (Introduction To Player/Missile Graphics, Figure 7)

List of POKEs, necessary for full employment of Player/Missile graphics

Memory location Operation
559
put a 62 here for a single-line, a 46 for double-line resolution
623

sets player/playfield priorities (only one bit on!)

    1: all players have priority over all playfield registers
    4: all playfield registers have priority over all players
    2: mixed. P0 & P1, then all playfield, then P2 & P3
    8: mixed, PF0 & PF1, then all players, then PF2 & PF3
704
color of player/missile 0
705
color of player/missile 1
706
color of player/missile 2
707
color of player/missile 3
53248
horizontal position of player 0
53249
horizontal position of player 1
53250
horizontal position of player 2
53251
horizontal position of player 3
53252
horizontal position of missile 0
53253
horizontal position of missile 1
53254
horizontal position of missile 2
53255
horizontal position of missile 3
53256
size of player 0 (0 = normal, 1 = double, 3 = quadruple)
53257
size of player 1 (0 = normal, 1 = double, 3 = quadruple)
53258
size of player 2 (0 = normal, 1 = double, 3 = quadruple)
53259
size of player 3 (0 = normal, 1 = double, 3 = quadruple)
53277
a 3 here enables player/missile graphics, a 0 disables them
54279
put high byte of PMBASE here