SNES-CD/SuperDisc/Nintendo Playstation story: A while back I had poked around at the SNES-CD BIOS. Found some of the error messages and decided to call those subroutines to draw them on screen 1/9 
Two messages caught my interest in particular: “Electronic Book” and “NOT EB”. At this point I discovered Sony had made an e-book player called the “Sony Data Discman” 2/9
A quick summary of Sony DD for those unfamiliar: It is a portable e-book player that loads books stored on 8cm CDs encased in a plastic caddy. Various models were in production from early 90s until early 2000s. 3/9
After poking around the BIOS some more with nocash, we found that the SNES-CD BIOS has support to load Sony Data Discman e-books… 4/9
The program that is in the ROM is really not complete and only provides basic functionality: Most of what on the display is garbage and the program is trying to access fonts outside of memory space. Can only reliably parse table-of-contents and main book 5/9
Some of the menus between the DD and SNES-CD share some similarity with responses such as “NG” - “Not Good?” (Images from TCRF tcrf.net/Super_Disc_Boo…) 6/9
For those interested, here is a picture of a Sony DD-8 motherboard with component annotations 7/9
Would not surprise me if there was cross-collaboration from Sony DD team and SNES-CD/SuperDisc during SuperDisc development.. Just an educated guess given these findings 8/9
If you want to see some old discussion on this Sony DD stuff in particular, check out my post on nesdev from ~3 years ago: forums.nesdev.com/viewtopic.php?… 9/9
Bonus: Here are some other pics of Sony DD test screens I didn't have room for
