In high school, I used to program the graphing calculators we used in math class. I started but never finished a Doom-like first-person shooter for the TI-83 graphing calculator, written in Z80 assembly language. Nostalgia compels me to publish it here.
DOOM 83 used to have a web site at http://members.tripod.com/mikendave/doom/. I have made an archive of that site.
The source refers to two files available from Texas Instruments, ti83asm.inc and tokens.inc.
Download doom.z80.
Though I haven't looked at the code thoroughly, it seems that doom.z80, which is the latest file I could find, may not be very functional because I was in the middle of testing something. You can download the last backup I made on November 11, 1999. I don't know if either of these files will assemble.