Retail Clerk '89 started as a personal exercise to learn Sega Genesis programming. It's now a complete, albeit short, demo. Although originally inspired by Phantasy Star II and III it morphed into more of an interactive fiction / casual adventure game. It's not especially fun but has a complete story.
Things implemented in this demo
Building
I have only ever built this using vasm (http://sun.hasenbraten.de/vasm/) with the motorola syntax module. I have no reason to believe this won't work with any other 68000 assembler. vasm command line that works: vasmm68k_mot -o RetailClerk89.bin -Fbin -spaces RetailClerk89.X68
In const_GameSettings.X68 there are flags that change the behavior of the demo. The most useful one is _DEBUG_ - setting it to $1 adds the debug menu and the speeds up the game. Setting _ATGAMES_HACKS to $1 fixes the audio on AtGames clone machines but breaks the demo on real hardware and some emulators. At some point I'll be smart enough to make those command-line arguments instead.
There are additional build tools that require Java 8+ in the /build-tools/ folder. These are not needed to compile the demo from source. However, they are needed if you want to customize sprites, collision maps, or change the memory map.
This has been fully tested on Gens and BlastEm for Linux. It has also been fully tested on real Genesis model 1 hardware using an Everdrive. It has been minimally tested on Genecyst for DOS, Gens for Windows, and Genesis Plus on Android. It runs on the AtGames Firecore (AKA 'Sega Ultimate Portable Game Player') and is likely to run on other AtGames clones but only the Firecore has been explicitly tested.
Links
Project page - https://www.huguesjohnson.com/rc89/
Builds that mostly work - https://www.huguesjohnson.com/rc89/releases.html
Disclaimers
This demo is (obviously) not licensed by Sega, there is no relationship between the author of this demo and Sega.
Although this demo is inspired by late 80s mall culture all locations, characters, and events are fictitious.