Completely confused by something here, and I have done some research, but I am hoping that someone can make sure that I have this right.

(Please note, I know this isn't in chronological order, I am just listing them)...

US original release was the Turbo Graffix 16, which plays only US cards.

Japan original release was the PC Engine or the PC Engine "Core" system (not sure???), which plays only Japanese HuCards.

US releases Turbo Graffix CD, an add-on which allows play of US CDs.

Japan releases the CD Rom 2, which can interface with the PC Engine, allowing the play of Japanese CDs.

US releases Turbo Duo, which is a combined unit, allowing play of US cards and CDs.

Japan releases the Turbo Duo, a combined unit which allows play of Japanese cards and CDs.

Now here is where it gets very, very fuzzy for me...

Japan releases the SuperGrafx which is a stand alone console that plays the SuperGrafx cards (about 5-7 of them), and all Japanese HuCards.????

Japan also releases the Super CDRom2 system which has an attachment that can allow for the play of HuCard games.????

Then, there are "Super CDs", "Arcade CDs", and system cards that you need to have to play each kind on the system.???

I could use some help here, obviously. This is probably the most confusing bunch of systems to someone who has never owned one of them.

For example, if I were to by a US TurboDuo (black box) - at least I am assuming that it's a US release; I could have that wrong...it would play US cards and US CDs??? Not imports.

Again, please help. It would be cool to get some input, rather than the standard...it's somewhere in a previous forum or something like that.

Thanks for any help.
Steve