I'm finally done with exams, and I have a two week break before the spring term starts (there's a course on Differential Geometry I couldn't resist ).  If I can get motivated, there should be a ton of progress.  Some stuff I have completely planned out:
- Invert the HUD
- Adjust display for when the player is near walls (instead of adding 3 blanks on every side display the sprite not in the center of the screen)
- New idea for movement: Have all commands for tiles in one program, and depending on the tile (which will just be an integer) copy the needed code to a subprogram and run the subprogram.  No need for If:Then or Goto/Lbl; just transfer the three or so lines at 3N-2 to a program and run it (might work well, might not; worth a try).
- Four more levels (they each contain some situations for tile arrangement that need special attending to)

If that does work, i might have use that idea for my project.

You have no idea how much that comment moved Chip's Challenge closer to the top of my "stuff to do when I'm bored" list (i.e. all my priorities).  Thanks

The initial testing of the new movement routine has gone very well.  There's been a pretty good speed increase, and the execution time for tiles is somewhat more uniform.  I believe the reason for these improvements is twofold: (1) There aren't as many If:Then blocks so there's less code to sift through, and (2) Many tiles have very similar actions/effects (like items, or doors, etc...) so certain things were being calculated as a function of tile number, but now, with the new system, everything is hard-coded.

I tried Celtic III's det(23 and det(24 commands and, except for a couple little bugs, there was an even larger speed increase.  det(24 doesn't strip the newline so very quickly my program got filled with tons of newlines _{hint hint}

These improvements have come at a cost of nearly doubling the size of movement code; what once took 583 bytes now takes 1115 bytes.  By rearranging certain commands common to all tiles (like the return value stating whether walkable or not) I should be able to cut out 2*48=96 bytes, but it's still much larger than what it was (but the program can be in the archive so it's not taking a chunk out of RAM).

[edit] Oh, and I've also finished with inverting the HUD and the modification to sprite display.

glad speed increased , btw is it still planned for 84+ only or will it also be for 83+ when finished?

The speed on an 83+ shouldn't be as horrendous as it used to be.  Because of that newline bug I haven't had many consistent tests with Indexfile/LookupIndex, but it's supposed to be a lot more consistent with access time so this does open the door to (possibly) fairly uniform frame rate, and thus a clock

Glad to see progress, you are doing some very notable things and I sullute you!

Thanks   I've decided to abuse Celtic III to its fullest.

Umm... I tried the demo.  Bad things happened.

Could you be a bit more specific please?

do u have one of these calculators with BOOT code 1.02 on it? (press MODE->ALPHA->S to know, then press ON/CLEAR to exit without clearing RAM) I know some ASM programs has trouble on them, such as RealSound and TI-Boy SE