BACK TO STRIPED elevators, based on feedback. I thought this would give me lots of RAM back - but it wasn't to be.
I really wanted to add stairs on either side of the screen, and I just couldn't fit it into the old kernel. So I've gone back (again) to the RAM-hungry kernel that supercat suggested.
And so now RAM is an issue. Probably can make it work, though.
So new binary: still isn't playable - I was too tired last night to add the code back in that moves you up a floor and increases your score - but the status stuff is back at the bottom of the screen: ElevRep20061105.bin
Thoughts on the stairs?
Other changes: I fixed the maid sprite and increased the height of the elevators. I also completely revamped the routine that moves the elevators. There are 64 elevator speeds; the one on the left is the slowest and the one on the right is the fastest.
I wrote special-case kernels for the top and bottom of the screen, so the kernel needs 65 bytes of RAM for the elevators, which isn't so bad - however, I also need 3 bytes for each elevator (Y position, fractional Y position, and velocity/direction); 21 bytes total.
Features requiring RAM that I want to add:
-MemCard support and high score support
-a second player (might be able to overlay other RAM for this)
I probably need between 10 and 12 free bytes to add all that; right now I have 3 free bytes. So we'll see what I can do.