For a while,  I have had an idea for Atari 5200 and A8 called Detective Powers. My old blog entry from 2015 has my original ideas.  Here is the original blurb for the game: 

Assume the role of the world’s most famous consulting detective, using investigation and deduction to navigate Baker Street, countryside manors, and interior room locations in a retro 80’s arcade-adventure style of game play. Find helpful items and clues, keep your Detective Powers fully charged and solve each case. Cases are based on several canonical Holmes stories by Sir Arthur Conan Doyle and are planned to include The Musgrave Ritual, The Dancing Men, The Hound of the Baskervilles, and The Final Problem. Sherlock Holmes Adventures is a 32K game for the Atari 8bit XL/XE computers and the Atari 5200 Supersystem.

I've worked on it now and then, but my goal of twin 5200 / A8 dev has been slow going.  I have 2 Atari 5200 engines at 32K, and 1 A8 engine at 64K using bank switching.  My attempts to make 1 64K engine that would produce twin 5200/A8 game ROMs hasn't been going too well. So I went back and just fooled around more with the original 32K 5200 code. I figure I can eventually copy this code to an A8 compatible shell.  But I was tired of fighting with the mechanics of bank switching and 5200 vs A8 registers. 

I took the prettier font/charset I used in Adventure II XE and I've got a shell going on 5200. This game is more text-intensive, and the 5200 version is currently in TASM (not DASM). I tried using the TASM .TEXT directive, but it only seemed to work with lower case letters.  If I put .TEXT "Hello World" , the capital letters don't translate to screen correctly.   I wrote a conversion macro so I can continue to use the .TEXT feature for the verbiage and not worry about capital/lower-case letter problems.    I haven't included any of the actual in-game screens into this engine yet.  First I'd like to understand better how to easily include the verbiage.   In the game, Holmes will talk to you as you play, as though you are Watson. Do something dumb, you'll read in the text box "Really Watson, this will NOT do!" 

I still have some more work to figure out how to more easily include lots of verbiage.