MACHINE CODE BLOCKS BY ADDRESS
C200-C3FF screen ram
C400-E163 tokenized basic lines
E164 setup F300-F7FF RAM
E240 overwrite line 10 with 10 REM ASCII for when game is re-RUN
F300 176-byte alien graphic
F400 176-byte alien graphic
F4C0 move F400 to F4B0 to C280 used by lines 8800 alien bouncing code
F4E0 move F300 to F3B0 to C287 used by lines 6500 alien still code
F500 alien and player positions
F590 modify C200
F5B8 screen switch load from table
F5D0 data table for screens to show in order
F5E5 current screen to show
F600 read keys player move hit walls and items
F700 alien move ai
F780 move memory block
F790 update things on screen
F7B0 alien caught player?
F7D0 update item numbers
F800 alien X position
F801 alien y position
F802 player x position
F803 player y position
F804 alien x next move direction flag
F805 alien y next move direction flag
F806 number items carried
F807 item 1 count
F808 item 2 count
F809 item 3 count
F80A item 4 count
F80B alien caught you flag
F80C unused?
F80D unused?
F80E unused?
F80F player hit something flag
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