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Little Lode Runner was Re: 48K stage-loaded to 64K single-load?
More details on this...
My old partial filecrack loads part of a memory dump, then fills in the
memory as Lode Runner expects, starting the program with the title screen
already drawn ($2000-3FFF) and the instruction pointer at $6047. By
moving the initial IP to $6008, I free up 2000-3FFF at load time.
So at load time, we have 07FD-07FF holding a JMP...
0800-0CFF, 0F00-1F00, 6000-8EFF holding code already in place...
0D00-0EFF, 4000-5FFF, 8F00-92FF and 9400-95FF holding code to move...
9300.93FF is reserved for my mover, and it's only about half used.
Obviously this means one can't merely BLOAD the game if I use any more
memory.
The code to call the CLI if Ctrl-E is pressed can be found at 61F9. NOP
out 4 bytes here and 3 more at 6211, the editor is no longer accessible.
The CLI itself appears to be located from 7B84-7C4C. I haven't yet found
the editor itself.
(The game engine is single load; only the levels need to be loaded off the
disk on demand. Also, it may be desirable to zot the high score table and
disable any routine to save it.)
-uso.