Since I was the one that submitted a chunk of the existing Japanese games in the PC-Engine / Duo databases I feel I should chime in.
First, it's kind of a bad system the way it's set up. Technically, there is no "Duo" category. PC Engine Duo / Turbo Duo are just product names for the consolidated hardware and are not required to play any CD-ROM content. Let me requote myself from an earlier post clearing up the PC Engine nonsense:
The original release was the TurboGraphx-16/PC Engine. It played HuCards only. Eventually the PC Engine/TurboGraphx-16 CD-ROM2 and the PC Engine Super CD-ROM2 (this didn't see a release stateside) were released as add-ons for it. They played CD-ROM games and Super CD-ROM games respectively.
To play Super CD-ROM2 games, you'd need a Super System Card. This would go in the HuCard slot. The TurboDuo and the PC Engine Duo had this built in.
In order to play Arcade CD-ROM2 games, you needed an Arcade Card. They were still PC Engine CD games though, not a new system. This was not built into the Duo systems thus Duos still needed the Arcade Card to play them.
The TurboDuo/PC Engine Duo didn't allow you to play any new/exclusive games, but just put everything into one nice compact package (short of the Arcade Card). Thus, it's not really its own system.
In short, all TG16/PCE games can fall under two categories for the sake of ultimate clarity. PC Engine HuCards and PC Engine CD-ROMs. If you wanted to get more technical, you could break it down to HuCards, CD-ROMs, Super CD-ROMs, and Arcade CD-ROMs.
The games that were marked Duo on the packaging stateside were done because they were Super CD-ROM2 games and were unplayable on the regular TG-16 CD consoles, thus making consumers purchase a Duo to play them. The alternative was to buy a PC Engine with a Super CD-ROM2 drive with a System Card.
Is it no wonder it wasn't a success in the states?
The SuperGraphx, however, is its own console. No equivalent came out in the US. It still utilized the HuCard media, and was backwards compatible with PC Engine HuCards, but it had only 7 unique games made for it that are only playable on a SuperGraphx. It also supported the PC Engine Super CD-ROM2 as an add-on. Think of it as the next iteration of the PC-Engine that just didn't take off.
Also, the spelling of the systems in my post should be the correct ones. Also, PC Engine CD-ROM2 would be pronounced "CD-ROM-ROM", and not "CD-ROM Two"
Thus this was a lesser of two evils thing. Again, there are NO games that can ONLY be played be played played on Duo hardware. With a PC Engine CD-ROM2 and an Arcade Card or Super System Card you can play any game that was released.
If we really wanted to clean it up and get technical, you'd have a Hu-Card table, a CD-ROM table, a Super CD-ROM table, and an Arcade CD-ROM table. At no point would a "Duo" table be neccessary since there is no "Duo" format for the PC Engine. But, as is, I think that a Hu-Card table and a CD-ROM table would get the job done.
If I'm incorrect on any of my details, please feel free to correct me.
Author
