121 Error?

[Reflectivity]

Okay, forgive me for not having much DDR knowledge. I don't play super hardcore or anything. >.>
The movie theatre has a DDR machine called "DRR MegaMix". It looks (and functions) EXACTLY like the machine in this video: https://www.youtube.com/watch?v=BzJ_FIYq7Bg
A couple of days ago, I went to the theatre and found this on the screen:
http://i.imgur.com/PWkkgIF.jpg
What does this mean, and is this a serious error? (I asked around for a translation on imgur, if nobody here knows Japanese. Here's what the commenter said: There's a problem with the cassette apparently that is preventing it from starting. It says refer to the manual for assistance.)
If the machine is totally screwed, well, there goes any chance of me playing arcade DDR. As much as I would like to own a machine, I am too young too (I am not old enough to have a job. )

[Fluffyumpkins]

Not really answering your question, but there may be other DDR machines in your area.

http://zenius-i-vanisher.com/v5.2/arcades.php

It's a good resource if you haven't seen it.

[Ho]

That's a security cartridge error. Each DDR game had a CD-ROM disc and an accompanying security cartridge that must be plugged into the machine (the system unit inside the cabinet). If the cartridge is not present or the wrong one, you get an error like the one you posted.

However, MegaMix is a bootleg mix, and a lot of the bootlegs modified the game to not require a security cartridge. Or, they required a security cartridge but didn't care what cartridge it was (i.e. it did not have to match the mix that was playing). I don't recall how MegaMix worked specifically (I think I have a copy of it, but I've run it maybe once) and there may be some variation.

It seems unlikely that the cartridge would just fall out, but I suppose it's possible if it wasn't fully seated in the system to begin with. This problem could be as simple as someone opening the machine and pushing the cartridge back in. Of course, that's not something that you can really do as a player. But it is a pretty simple problem that hopefully the tech who services that machine can figure out.

Good luck! I hope you get to play again soon.

[Reflectivity]

Not really answering your question, but there may be other DDR machines in your area.

http://zenius-i-vanisher.com/v5.2/arcades.php

It's a good resource if you haven't seen it.

Checked it out, unfortunately no other ones are in my city (or anywhere that isn't at least an hour's drive away. ) The machine isn't even marked, I'll have to do that sometime soon.

That's a security cartridge error. Each DDR game had a CD-ROM disc and an accompanying security cartridge that must be plugged into the machine (the system unit inside the cabinet). If the cartridge is not present or the wrong one, you get an error like the one you posted.

However, MegaMix is a bootleg mix, and a lot of the bootlegs modified the game to not require a security cartridge. Or, they required a security cartridge but didn't care what cartridge it was (i.e. it did not have to match the mix that was playing). I don't recall how MegaMix worked specifically (I think I have a copy of it, but I've run it maybe once) and there may be some variation.

It seems unlikely that the cartridge would just fall out, but I suppose it's possible if it wasn't fully seated in the system to begin with. This problem could be as simple as someone opening the machine and pushing the cartridge back in. Of course, that's not something that you can really do as a player. But it is a pretty simple problem that hopefully the tech who services that machine can figure out.

Good luck! I hope you get to play again soon.

Okay, that makes sense. Thanks a ton for the quick reply!
Megamix is a bootlegged EXTREME, right? It would seem so, comparing them. I was planning to mark it in the arcade map (see above,) just wanted to be sure.
I really hope they figure it out too, otherwise I'll be limited to home with beware's EXTREME and my softpad mat

[Ho]

Megamix is a bootlegged EXTREME, right? It would seem so, comparing them. I was planning to mark it in the arcade map (see above,) just wanted to be sure.

Yes, that's right.

[Reflectivity]

Update!

The machine is back up and the graphics are shit. The monitor bounces a bit when a big bass note is played. The background is all blue. The timer is flipped upside down, and seems to be at 50% opacity. The groove radar is twice the size it normally is and also is at 50% opacity. >.> Edit data can also be accessed for some reason even though there is no card reader. 2P up arrow doesn't even work.

Thinking about taking a video. It's so shitty xD

[MonMotha]

Edit data can also be accessed for some reason even though there is no card reader.

This is normal. The graphics oddities may just be because, well, Megamix had crappy graphics. Somebody basically took an editor to the thing and played with stuff to make it "cool" for some reason. There's not any extra data - no new songs, charts, etc. There's zero reason to run Megamix over Extreme, but of course that's not what the operators were told. The other issues, well, it's a trashy machine.

The monitor shaking when a bass note is played is probably a bad solder joint. Whack the side of the cabinet with your hand a few times and see if the same thing happens. If it does, inspect the monitor deflection (chassis) board for bad solder joints. Especially check the connectors.